Merge pull request #207 from SquidDev-CC/feature/cleanup

Fix a couple of warnings

build.gradle

@@ -83,3 +83,8 @@ processResources
     }
 }
 
+gradle.projectsEvaluated {
+    tasks.withType(JavaCompile) {
+        options.compilerArgs << "-Xlint"
+    }
+}

src/main/java/dan200/computercraft/ComputerCraft.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -74,18 +74,23 @@ import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 ///////////////
 // UNIVERSAL //
 ///////////////
 
 @Mod(
-    modid = "ComputerCraft", name = "ComputerCraft", version = "${version}",
+    modid = ComputerCraft.MOD_ID, name = "ComputerCraft", version = "${version}",
     guiFactory = "dan200.computercraft.client.gui.GuiConfigCC$Factory"
 )
 public class ComputerCraft
 {
+    public static final String MOD_ID = "ComputerCraft";
+
     // GUI IDs
     public static final int diskDriveGUIID = 100;
     public static final int computerGUIID = 101;
@@ -209,7 +214,7 @@ public class ComputerCraft
     private static final Map<String, IPocketUpgrade> pocketUpgrades = new HashMap<String, IPocketUpgrade>();
 
     // Implementation
-    @Mod.Instance( value = "ComputerCraft" )
+    @Mod.Instance( value = ComputerCraft.MOD_ID )
     public static ComputerCraft instance;
 
     @SidedProxy( clientSide = "dan200.computercraft.client.proxy.ComputerCraftProxyClient", serverSide = "dan200.computercraft.server.proxy.ComputerCraftProxyServer" )
@@ -509,9 +514,8 @@ public class ComputerCraft
             }
         }
 
-        for( int i=0; i<permissionProviders.size(); ++i )
+        for( ITurtlePermissionProvider provider : permissionProviders )
         {
-            ITurtlePermissionProvider provider = permissionProviders.get( i );
             if( !provider.isBlockEnterable( world, pos ) )
             {
                 return false;
@@ -531,9 +535,8 @@ public class ComputerCraft
             }
         }
 
-        for( int i=0; i<permissionProviders.size(); ++i )
+        for( ITurtlePermissionProvider provider : permissionProviders )
         {
-            ITurtlePermissionProvider provider = permissionProviders.get( i );
             if( !provider.isBlockEditable( world, pos ) )
             {
                 return false;
@@ -581,13 +584,11 @@ public class ComputerCraft
     public static IPeripheral getPeripheralAt( World world, BlockPos pos, EnumFacing side )
     {
         // Try the handlers in order:
-        Iterator<IPeripheralProvider> it = peripheralProviders.iterator();
+        for( IPeripheralProvider peripheralProvider : peripheralProviders )
-        while( it.hasNext() )
         {
             try
             {
-                IPeripheralProvider handler = it.next();
+                IPeripheral peripheral = peripheralProvider.getPeripheral( world, pos, side );
-                IPeripheral peripheral = handler.getPeripheral( world, pos, side );
                 if( peripheral != null )
                 {
                     return peripheral;
@@ -620,13 +621,11 @@ public class ComputerCraft
 
         // Try the handlers in order:
         int combinedSignal = -1;
-        Iterator<IBundledRedstoneProvider> it = bundledRedstoneProviders.iterator();
+        for( IBundledRedstoneProvider bundledRedstoneProvider : bundledRedstoneProviders )
-        while( it.hasNext() )
         {
             try
             {
-                IBundledRedstoneProvider handler = it.next();
+                int signal = bundledRedstoneProvider.getBundledRedstoneOutput( world, pos, side );
-                int signal = handler.getBundledRedstoneOutput( world, pos, side );
                 if( signal >= 0 )
                 {
                     if( combinedSignal < 0 )
@@ -652,13 +651,11 @@ public class ComputerCraft
         if( stack != null )
         {
             // Try the handlers in order:
-            Iterator<IMediaProvider> it = mediaProviders.iterator();
+            for( IMediaProvider mediaProvider : mediaProviders )
-            while( it.hasNext() )
             {
                 try
                 {
-                    IMediaProvider handler = it.next();
+                    IMedia media = mediaProvider.getMedia( stack );
-                    IMedia media = handler.getMedia( stack );
                     if( media != null )
                     {
                         return media;
@@ -722,7 +719,7 @@ public class ComputerCraft
         }
     }
 
-    public static IMount createResourceMount( Class modClass, String domain, String subPath )
+    public static IMount createResourceMount( Class<?> modClass, String domain, String subPath )
     {
         // Start building list of mounts
         List<IMount> mounts = new ArrayList<IMount>();
@@ -760,11 +757,11 @@ public class ComputerCraft
         if( resourcePackDir.exists() && resourcePackDir.isDirectory() )
         {
             String[] resourcePacks = resourcePackDir.list();
-            for( int i=0; i<resourcePacks.length; ++i )
+            for( String resourcePack1 : resourcePacks )
             {
                 try
                 {
-                    File resourcePack = new File( resourcePackDir, resourcePacks[i] );
+                    File resourcePack = new File( resourcePackDir, resourcePack1 );
                     if( !resourcePack.isDirectory() )
                     {
                         // Mount a resource pack from a jar
@@ -806,7 +803,7 @@ public class ComputerCraft
         }
     }
 
-    private static File getContainingJar( Class modClass )
+    private static File getContainingJar( Class<?> modClass )
     {
         String path = modClass.getProtectionDomain().getCodeSource().getLocation().getPath();
         int bangIndex = path.indexOf( "!" );
@@ -831,7 +828,7 @@ public class ComputerCraft
         return file;
     }
 
-    private static File getDebugCodeDir( Class modClass )
+    private static File getDebugCodeDir( Class<?> modClass )
     {
         String path = modClass.getProtectionDomain().getCodeSource().getLocation().getPath();
         int bangIndex = path.indexOf("!");

src/main/java/dan200/computercraft/api/ComputerCraftAPI.java

@@ -21,6 +21,8 @@ import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.lang.reflect.Method;
 
 /**
@@ -36,6 +38,7 @@ public final class ComputerCraftAPI
         return computerCraft != null;
     }
 
+    @Nonnull
     public static String getInstalledVersion()
     {
         findCC();
@@ -50,6 +53,7 @@ public final class ComputerCraftAPI
         return "";
     }
 
+    @Nonnull
     public static String getAPIVersion()
     {
         return "${version}";
@@ -68,7 +72,7 @@ public final class ComputerCraftAPI
      * available for writing.
      * @see #createSaveDirMount(World, String, long)
      */
-    public static int createUniqueNumberedSaveDir( World world, String parentSubPath )
+    public static int createUniqueNumberedSaveDir( @Nonnull World world, @Nonnull String parentSubPath )
     {
         findCC();
         if( computerCraft_createUniqueNumberedSaveDir != null )
@@ -100,7 +104,8 @@ public final class ComputerCraftAPI
      * @see IMount
      * @see IWritableMount
      */
-    public static IWritableMount createSaveDirMount( World world, String subPath, long capacity )
+    @Nullable
+    public static IWritableMount createSaveDirMount( @Nonnull World world, @Nonnull String subPath, long capacity )
     {
         findCC();
         if( computerCraft_createSaveDirMount != null )
@@ -132,7 +137,8 @@ public final class ComputerCraftAPI
      * @see IComputerAccess#mountWritable(String, IWritableMount)
      * @see IMount
      */
-    public static IMount createResourceMount( Class modClass, String domain, String subPath )
+    @Nullable
+    public static IMount createResourceMount( @Nonnull Class<?> modClass, @Nonnull String domain, @Nonnull String subPath )
     {
         findCC();
         if( computerCraft_createResourceMount != null )
@@ -153,7 +159,7 @@ public final class ComputerCraftAPI
      * @see dan200.computercraft.api.peripheral.IPeripheral
      * @see dan200.computercraft.api.peripheral.IPeripheralProvider
      */
-    public static void registerPeripheralProvider( IPeripheralProvider handler )
+    public static void registerPeripheralProvider( @Nonnull IPeripheralProvider handler )
     {
         findCC();
         if ( computerCraft_registerPeripheralProvider != null)
@@ -174,7 +180,7 @@ public final class ComputerCraftAPI
      * @param upgrade The turtle upgrade to register.
      * @see dan200.computercraft.api.turtle.ITurtleUpgrade
      */
-    public static void registerTurtleUpgrade( ITurtleUpgrade upgrade )
+    public static void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade )
     {
         if( upgrade != null )
         {
@@ -196,7 +202,7 @@ public final class ComputerCraftAPI
      * @param handler The bundled redstone provider to register.
      * @see dan200.computercraft.api.redstone.IBundledRedstoneProvider
      */
-    public static void registerBundledRedstoneProvider( IBundledRedstoneProvider handler )
+    public static void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider handler )
     {
         findCC();
         if( computerCraft_registerBundledRedstoneProvider != null )
@@ -219,7 +225,7 @@ public final class ComputerCraftAPI
      * If there is no block capable of emitting bundled redstone at the location, -1 will be returned.
      * @see dan200.computercraft.api.redstone.IBundledRedstoneProvider
      */
-    public static int getBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side )
+    public static int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
     {
         findCC();
         if( computerCraft_getDefaultBundledRedstoneOutput != null )
@@ -239,7 +245,7 @@ public final class ComputerCraftAPI
      * @param handler The media provider to register.
      * @see dan200.computercraft.api.media.IMediaProvider
      */
-    public static void registerMediaProvider( IMediaProvider handler )
+    public static void registerMediaProvider( @Nonnull IMediaProvider handler )
     {
         findCC();
         if( computerCraft_registerMediaProvider != null )
@@ -258,7 +264,7 @@ public final class ComputerCraftAPI
      * @param handler The turtle permission provider to register.
      * @see dan200.computercraft.api.permissions.ITurtlePermissionProvider
      */
-    public static void registerPermissionProvider( ITurtlePermissionProvider handler )
+    public static void registerPermissionProvider( @Nonnull ITurtlePermissionProvider handler )
     {
         findCC();
         if( computerCraft_registerPermissionProvider != null )
@@ -271,7 +277,8 @@ public final class ComputerCraftAPI
         }
     }
 
-    public static void registerPocketUpgrade(IPocketUpgrade upgrade) {
+    public static void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
+    {
         findCC();
         if(computerCraft_registerPocketUpgrade != null) {
             try {
@@ -291,36 +298,36 @@ public final class ComputerCraftAPI
         if( !ccSearched ) {
             try {
                 computerCraft = Class.forName( "dan200.computercraft.ComputerCraft" );
-                computerCraft_getVersion = findCCMethod( "getVersion", new Class[]{
+                computerCraft_getVersion = findCCMethod( "getVersion", new Class<?>[]{
                 } );
-                computerCraft_createUniqueNumberedSaveDir = findCCMethod( "createUniqueNumberedSaveDir", new Class[]{
+                computerCraft_createUniqueNumberedSaveDir = findCCMethod( "createUniqueNumberedSaveDir", new Class<?>[]{
                     World.class, String.class
                 } );
-                computerCraft_createSaveDirMount = findCCMethod( "createSaveDirMount", new Class[] {
+                computerCraft_createSaveDirMount = findCCMethod( "createSaveDirMount", new Class<?>[] {
                     World.class, String.class, Long.TYPE
                 } );
-                computerCraft_createResourceMount = findCCMethod( "createResourceMount", new Class[] {
+                computerCraft_createResourceMount = findCCMethod( "createResourceMount", new Class<?>[] {
                     Class.class, String.class, String.class
                 } );
-                computerCraft_registerPeripheralProvider = findCCMethod( "registerPeripheralProvider", new Class[] {
+                computerCraft_registerPeripheralProvider = findCCMethod( "registerPeripheralProvider", new Class<?>[] {
                     IPeripheralProvider.class
                 } );
-                computerCraft_registerTurtleUpgrade = findCCMethod( "registerTurtleUpgrade", new Class[] {
+                computerCraft_registerTurtleUpgrade = findCCMethod( "registerTurtleUpgrade", new Class<?>[] {
                     ITurtleUpgrade.class
                 } );
-                computerCraft_registerBundledRedstoneProvider = findCCMethod( "registerBundledRedstoneProvider", new Class[] {
+                computerCraft_registerBundledRedstoneProvider = findCCMethod( "registerBundledRedstoneProvider", new Class<?>[] {
                     IBundledRedstoneProvider.class
                 } );
-                computerCraft_getDefaultBundledRedstoneOutput = findCCMethod( "getDefaultBundledRedstoneOutput", new Class[] {
+                computerCraft_getDefaultBundledRedstoneOutput = findCCMethod( "getDefaultBundledRedstoneOutput", new Class<?>[] {
                     World.class, BlockPos.class, EnumFacing.class
                 } );
-                computerCraft_registerMediaProvider = findCCMethod( "registerMediaProvider", new Class[] {
+                computerCraft_registerMediaProvider = findCCMethod( "registerMediaProvider", new Class<?>[] {
                     IMediaProvider.class
                 } );
-                computerCraft_registerPermissionProvider = findCCMethod( "registerPermissionProvider", new Class[] {
+                computerCraft_registerPermissionProvider = findCCMethod( "registerPermissionProvider", new Class<?>[] {
                     ITurtlePermissionProvider.class
                 } );
-                computerCraft_registerPocketUpgrade = findCCMethod( "registerPocketUpgrade", new Class[] {
+                computerCraft_registerPocketUpgrade = findCCMethod( "registerPocketUpgrade", new Class<?>[] {
                     IPocketUpgrade.class
                 } );
             } catch( Exception e ) {
@@ -331,7 +338,7 @@ public final class ComputerCraftAPI
         }
     }
 
-    private static Method findCCMethod( String name, Class[] args )
+    private static Method findCCMethod( String name, Class<?>[] args )
     {
         try {
             if( computerCraft != null )
@@ -346,7 +353,7 @@ public final class ComputerCraftAPI
     }
 
     private static boolean ccSearched = false;
-    private static Class computerCraft = null;
+    private static Class<?> computerCraft = null;
     private static Method computerCraft_getVersion = null;
     private static Method computerCraft_createUniqueNumberedSaveDir = null;
     private static Method computerCraft_createSaveDirMount = null;

src/main/java/dan200/computercraft/api/filesystem/IMount.java

@@ -10,6 +10,7 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
@@ -36,7 +37,7 @@ public interface IMount
      * @return If the file exists.
      * @throws IOException If an error occurs when checking the existence of the file.
      */
-    public boolean exists( String path ) throws IOException;
+    boolean exists( @Nonnull String path ) throws IOException;
 
     /**
      * Returns whether a file with a given path is a directory or not.
@@ -45,7 +46,7 @@ public interface IMount
      * @return If the file exists and is a directory
      * @throws IOException If an error occurs when checking whether the file is a directory.
      */
-    public boolean isDirectory( String path ) throws IOException;
+    boolean isDirectory( @Nonnull String path ) throws IOException;
 
     /**
      * Returns the file names of all the files in a directory.
@@ -54,7 +55,7 @@ public interface IMount
      * @param contents A list of strings. Add all the file names to this list.
      * @throws IOException If the file was not a directory, or could not be listed.
      */
-    public void list( String path, List<String> contents ) throws IOException;
+    void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException;
 
     /**
      * Returns the size of a file with a given path, in bytes
@@ -63,7 +64,7 @@ public interface IMount
      * @return The size of the file, in bytes.
      * @throws IOException If the file does not exist, or its size could not be determined.
      */
-    public long getSize( String path ) throws IOException;
+    long getSize( @Nonnull String path ) throws IOException;
 
     /**
      * Opens a file with a given path, and returns an {@link InputStream} representing its contents.
@@ -72,5 +73,6 @@ public interface IMount
      * @return A stream representing the contents of the file.
      * @throws IOException If the file does not exist, or could not be opened.
      */
-    public InputStream openForRead( String path ) throws IOException;
+    @Nonnull
+    InputStream openForRead( @Nonnull String path ) throws IOException;
 }

src/main/java/dan200/computercraft/api/filesystem/IWritableMount.java

@@ -10,6 +10,7 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.OutputStream;
 
@@ -33,7 +34,7 @@ public interface IWritableMount extends IMount
      * @param path A file path in normalised format, relative to the mount location. ie: "programs/mynewprograms".
      * @throws IOException If the directory already exists or could not be created.
      */
-    public void makeDirectory( String path ) throws IOException;
+    void makeDirectory( @Nonnull String path ) throws IOException;
 
     /**
      * Deletes a directory at a given path inside the virtual file system.
@@ -41,7 +42,7 @@ public interface IWritableMount extends IMount
      * @param path A file path in normalised format, relative to the mount location. ie: "programs/myoldprograms".
      * @throws IOException If the file does not exist or could not be deleted.
      */
-    public void delete( String path ) throws IOException;
+    void delete( @Nonnull String path ) throws IOException;
 
     /**
      * Opens a file with a given path, and returns an {@link OutputStream} for writing to it.
@@ -50,7 +51,8 @@ public interface IWritableMount extends IMount
      * @return A stream for writing to
      * @throws IOException If the file could not be opened for writing.
      */
-    public OutputStream openForWrite( String path ) throws IOException;
+    @Nonnull
+    OutputStream openForWrite( @Nonnull String path ) throws IOException;
 
     /**
      * Opens a file with a given path, and returns an {@link OutputStream} for appending to it.
@@ -59,7 +61,8 @@ public interface IWritableMount extends IMount
      * @return A stream for writing to.
      * @throws IOException If the file could not be opened for writing.
      */
-    public OutputStream openForAppend( String path ) throws IOException;
+    @Nonnull
+    OutputStream openForAppend( @Nonnull String path ) throws IOException;
 
     /**
      * Get the amount of free space on the mount, in bytes. You should decrease this value as the user writes to the
@@ -68,5 +71,5 @@ public interface IWritableMount extends IMount
      * @return The amount of free space, in bytes.
      * @throws IOException If the remaining space could not be computed.
      */
-    public long getRemainingSpace() throws IOException;
+    long getRemainingSpace() throws IOException;
 }

src/main/java/dan200/computercraft/api/lua/ILuaContext.java

@@ -6,6 +6,9 @@
 
 package dan200.computercraft.api.lua;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * An interface passed to peripherals and {@link ILuaObject}s by computers or turtles, providing methods
  * that allow the peripheral call to wait for events before returning, just like in lua. This is very useful if you need
@@ -28,7 +31,8 @@ public interface ILuaContext
      *                              event, InterruptedException will be thrown. This exception must not be caught or
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      */
-    public Object[] pullEvent( String filter ) throws LuaException, InterruptedException;
+    @Nonnull
+    Object[] pullEvent( @Nullable String filter ) throws LuaException, InterruptedException;
 
     /**
      * The same as {@link #pullEvent(String)}, except "terminated" events are ignored. Only use this if you want to
@@ -42,7 +46,8 @@ public interface ILuaContext
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      * @see #pullEvent(String)
      */
-    public Object[] pullEventRaw( String filter ) throws InterruptedException;
+    @Nonnull
+    Object[] pullEventRaw( @Nullable String filter ) throws InterruptedException;
 
     /**
      * Yield the current coroutine with some arguments until it is resumed. This method is exactly equivalent to
@@ -55,7 +60,8 @@ public interface ILuaContext
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      * @see #pullEvent(String)
      */
-    public Object[] yield( Object[] arguments ) throws InterruptedException;
+    @Nonnull
+    Object[] yield( @Nullable Object[] arguments ) throws InterruptedException;
 
     /**
      * Queue a task to be executed on the main server thread at the beginning of next tick, waiting for it to complete.
@@ -71,7 +77,8 @@ public interface ILuaContext
      *                              InterruptedException will be thrown. This exception must not be caught or
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      */
-    public Object[] executeMainThreadTask( ILuaTask task ) throws LuaException, InterruptedException;
+    @Nullable
+    Object[] executeMainThreadTask( @Nonnull ILuaTask task ) throws LuaException, InterruptedException;
 
     /**
      * Queue a task to be executed on the main server thread at the beginning of next tick, but do not wait for it to
@@ -86,5 +93,5 @@ public interface ILuaContext
      * @return The "id" of the task. This will be the first argument to the {@code task_completed} event.
      * @throws LuaException If the task could not be queued.
      */
-    public long issueMainThreadTask( ILuaTask task ) throws LuaException;
+    long issueMainThreadTask( @Nonnull ILuaTask task ) throws LuaException;
 }

src/main/java/dan200/computercraft/api/lua/ILuaObject.java

@@ -9,6 +9,9 @@ package dan200.computercraft.api.lua;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IPeripheral;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * An interface for representing custom objects returned by {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}
  * calls.
@@ -24,7 +27,8 @@ public interface ILuaObject
      * @return The method names this object provides.
      * @see IPeripheral#getMethodNames()
      */
-    public String[] getMethodNames();
+    @Nonnull
+    String[] getMethodNames();
 
     /**
      * Called when a user calls one of the methods that this object implements. This works the same as
@@ -47,5 +51,6 @@ public interface ILuaObject
      *                              intercepted, or the computer will leak memory and end up in a broken state.w
      * @see IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])
      */
-    public Object[] callMethod( ILuaContext context, int method, Object[] arguments ) throws LuaException, InterruptedException;
+    @Nullable
+    Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;
 }

src/main/java/dan200/computercraft/api/lua/ILuaTask.java

@@ -6,6 +6,8 @@
 
 package dan200.computercraft.api.lua;
 
+import javax.annotation.Nullable;
+
 /**
  * A task which can be executed via {@link ILuaContext#executeMainThreadTask(ILuaTask)} or
  * {@link ILuaContext#issueMainThreadTask(ILuaTask)}. This will be run on the main thread, at the beginning of the
@@ -25,5 +27,6 @@ public interface ILuaTask
      *                      same message as your exception. Use this to throw appropriate errors if the wrong
      *                      arguments are supplied to your method.
      */
-    public Object[] execute() throws LuaException;
+    @Nullable
+    Object[] execute() throws LuaException;
 }

src/main/java/dan200/computercraft/api/lua/LuaException.java

@@ -6,6 +6,8 @@
 
 package dan200.computercraft.api.lua;
 
+import javax.annotation.Nullable;
+
 /**
  * An exception representing an error in Lua, like that raised by the {@code error()} function.
  */
@@ -19,12 +21,12 @@ public class LuaException extends Exception
         this( "error", 1 );
     }
 
-    public LuaException( String message )
+    public LuaException( @Nullable String message )
     {
         this( message, 1 );
     }
 
-    public LuaException( String message, int level )
+    public LuaException( @Nullable String message, int level )
     {
         super( message );
         m_level = level;

src/main/java/dan200/computercraft/api/media/IMedia.java

@@ -11,6 +11,9 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.util.SoundEvent;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * Represents an item that can be placed in a disk drive and used by a Computer.
  * Implement this interface on your Item class to allow it to be used in the drive.
@@ -23,7 +26,8 @@ public interface IMedia
      * @param stack The itemstack to inspect.
      * @return The label. ie: "Dan's Programs".
      */
-    public String getLabel( ItemStack stack );
+    @Nullable
+    String getLabel( @Nonnull ItemStack stack );
 
     /**
      * Set a string representing the label of this item. Will be called vi {@code disk.setLabel()} in lua.
@@ -32,7 +36,7 @@ public interface IMedia
      * @param label The string to set the label to.
      * @return true if the label was updated, false if the label may not be modified.
      */
-    public boolean setLabel( ItemStack stack, String label );
+    boolean setLabel( @Nonnull ItemStack stack, @Nullable String label );
 
     /**
      * If this disk represents an item with audio (like a record), get the readable name of the audio track. ie:
@@ -41,7 +45,8 @@ public interface IMedia
      * @param stack The itemstack to inspect.
      * @return The name, or null if this item does not represent an item with audio.
      */
-    public String getAudioTitle( ItemStack stack );
+    @Nullable
+    String getAudioTitle( @Nonnull ItemStack stack );
 
     /**
      * If this disk represents an item with audio (like a record), get the resource name of the audio track to play.
@@ -49,7 +54,8 @@ public interface IMedia
      * @param stack The itemstack to inspect.
      * @return The name, or null if this item does not represent an item with audio.
      */
-    public SoundEvent getAudio( ItemStack stack );
+    @Nullable
+    SoundEvent getAudio( @Nonnull ItemStack stack );
 
     /**
      * If this disk represents an item with data (like a floppy disk), get a mount representing it's contents. This will
@@ -64,5 +70,6 @@ public interface IMedia
      * @see dan200.computercraft.api.ComputerCraftAPI#createSaveDirMount(World, String, long)
      * @see dan200.computercraft.api.ComputerCraftAPI#createResourceMount(Class, String, String)
      */
-    public IMount createDataMount( ItemStack stack, World world );
+    @Nullable
+    IMount createDataMount( @Nonnull ItemStack stack, @Nonnull World world );
 }

src/main/java/dan200/computercraft/api/media/IMediaProvider.java

@@ -8,6 +8,9 @@ package dan200.computercraft.api.media;
 
 import net.minecraft.item.ItemStack;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * This interface is used to provide {@link IMedia} implementations for {@link ItemStack}.
  *
@@ -22,5 +25,6 @@ public interface IMediaProvider
      * @return An IMedia implementation, or null if the item is not something you wish to handle
      * @see dan200.computercraft.api.ComputerCraftAPI#registerMediaProvider(IMediaProvider)
      */
-    public IMedia getMedia( ItemStack stack );
+    @Nullable
+    IMedia getMedia( @Nonnull ItemStack stack );
 }

src/main/java/dan200/computercraft/api/peripheral/IComputerAccess.java

@@ -11,6 +11,9 @@ import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * The interface passed to peripherals by computers or turtles, providing methods
  * that they can call. This should not be implemented by your classes. Do not interact
@@ -33,7 +36,8 @@ public interface IComputerAccess
      * @see #unmount(String)
      * @see IMount
      */
-    public String mount( String desiredLocation, IMount mount );
+    @Nullable
+    String mount( @Nonnull String desiredLocation, @Nonnull IMount mount );
 
     /**
      * Mount a mount onto the computer's file system in a read only mode.
@@ -51,7 +55,8 @@ public interface IComputerAccess
      * @see #unmount(String)
      * @see IMount
      */
-    public String mount( String desiredLocation, IMount mount, String driveName );
+    @Nullable
+    String mount( @Nonnull String desiredLocation, @Nonnull IMount mount, @Nonnull String driveName );
 
     /**
      * Mount a mount onto the computer's file system in a writable mode.
@@ -67,7 +72,8 @@ public interface IComputerAccess
      * @see #unmount(String)
      * @see IMount
      */
-    public String mountWritable( String desiredLocation, IWritableMount mount );
+    @Nullable
+    String mountWritable( @Nonnull String desiredLocation, @Nonnull IWritableMount mount );
 
     /**
      * Mount a mount onto the computer's file system in a writable mode.
@@ -84,7 +90,7 @@ public interface IComputerAccess
      * @see #unmount(String)
      * @see IMount
      */
-    public String mountWritable( String desiredLocation, IWritableMount mount, String driveName );
+    String mountWritable( @Nonnull String desiredLocation, @Nonnull IWritableMount mount, @Nonnull String driveName );
 
     /**
      * Unmounts a directory previously mounted onto the computers file system by {@link #mount(String, IMount)}
@@ -104,7 +110,7 @@ public interface IComputerAccess
      * @see #mount(String, IMount)
      * @see #mountWritable(String, IWritableMount)
      */
-    public void unmount( String location );
+    void unmount( @Nullable String location );
 
     /**
      * Returns the numerical ID of this computer.
@@ -114,7 +120,7 @@ public interface IComputerAccess
      *
      * @return The identifier.
      */
-    public int getID();
+    int getID();
 
     /**
      * Causes an event to be raised on this computer, which the computer can respond to by calling
@@ -134,7 +140,7 @@ public interface IComputerAccess
      * @throws RuntimeException If the peripheral has been detached.
      * @see dan200.computercraft.api.peripheral.IPeripheral#callMethod
      */
-    public void queueEvent( String event, Object[] arguments );
+    void queueEvent( @Nonnull String event, @Nullable Object[] arguments );
 
     /**
      * Get a string, unique to the computer, by which the computer refers to this peripheral.
@@ -146,5 +152,6 @@ public interface IComputerAccess
      * @return A string unique to the computer, but not globally.
      * @throws RuntimeException If the peripheral has been detached.
      */
-    public String getAttachmentName();
+    @Nonnull
+    String getAttachmentName();
 }

src/main/java/dan200/computercraft/api/peripheral/IPeripheral.java

@@ -9,6 +9,9 @@ package dan200.computercraft.api.peripheral;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * The interface that defines a peripheral. See {@link IPeripheralProvider} for how to associate blocks with peripherals.
  */
@@ -20,7 +23,8 @@ public interface IPeripheral
      *
      * @return A string identifying the type of peripheral.
      */
-    public String getType();
+    @Nonnull
+    String getType();
 
     /**
      * Should return an array of strings that identify the methods that this
@@ -30,7 +34,8 @@ public interface IPeripheral
      * @return An array of strings representing method names.
      * @see #callMethod
      */
-    public String[] getMethodNames();
+    @Nonnull
+    String[] getMethodNames();
 
     /**
      * This is called when a lua program on an attached computer calls {@code peripheral.call()} with
@@ -66,7 +71,8 @@ public interface IPeripheral
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      * @see #getMethodNames
      */
-    public Object[] callMethod( IComputerAccess computer, ILuaContext context, int method, Object[] arguments ) throws LuaException, InterruptedException;
+    @Nullable
+    Object[] callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;
 
     /**
      * Is called when canAttachToSide has returned true, and a computer is attaching to the peripheral.
@@ -85,7 +91,7 @@ public interface IPeripheral
      *                 computers can be attached to a peripheral at once.
      * @see #detach
      */
-    public void attach( IComputerAccess computer );
+    void attach( @Nonnull IComputerAccess computer );
 
     /**
      * Is called when a computer is detaching from the peripheral.
@@ -102,7 +108,7 @@ public interface IPeripheral
      *                 computers can be attached to a peripheral at once.
      * @see #detach
      */
-    public void detach( IComputerAccess computer );
+    void detach( @Nonnull IComputerAccess computer );
 
     /**
      * Determine whether this peripheral is equivalent to another one.
@@ -113,5 +119,5 @@ public interface IPeripheral
      * @param other The peripheral to compare against. This may be {@code null}.
      * @return Whether these peripherals are equivalent.
      */
-    public boolean equals( IPeripheral other );
+    boolean equals( @Nullable IPeripheral other );
 }

src/main/java/dan200/computercraft/api/peripheral/IPeripheralProvider.java

@@ -10,6 +10,9 @@ import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * This interface is used to create peripheral implementations for blocks.
  *
@@ -26,5 +29,6 @@ public interface IPeripheralProvider
      * @return A peripheral, or {@code null} if there is not a peripheral here you'd like to handle.
      * @see dan200.computercraft.api.ComputerCraftAPI#registerPeripheralProvider(IPeripheralProvider)
      */
-    public IPeripheral getPeripheral( World world, BlockPos pos, EnumFacing side );
+    @Nullable
+    IPeripheral getPeripheral( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side );
 }

src/main/java/dan200/computercraft/api/permissions/ITurtlePermissionProvider.java

@@ -9,6 +9,8 @@ package dan200.computercraft.api.permissions;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+
 /**
  * This interface is used to restrict where turtles can move or build.
  *
@@ -25,7 +27,7 @@ public interface ITurtlePermissionProvider
      * @param pos   The location of the block.
      * @return Whether the turtle can move into this block.
      */
-    public boolean isBlockEnterable( World world, BlockPos pos );
+    boolean isBlockEnterable( @Nonnull World world, @Nonnull BlockPos pos );
 
     /**
      * Determine whether a block can be modified by a turtle.
@@ -36,5 +38,5 @@ public interface ITurtlePermissionProvider
      * @param pos   The location of the block.
      * @return Whether the turtle can modify this block.
      */
-    public boolean isBlockEditable( World world, BlockPos pos );
+    boolean isBlockEditable( @Nonnull World world, @Nonnull BlockPos pos );
 }

src/main/java/dan200/computercraft/api/redstone/IBundledRedstoneProvider.java

@@ -10,6 +10,8 @@ import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+
 /**
  * This interface is used to provide bundled redstone output for blocks.
  *
@@ -27,5 +29,5 @@ public interface IBundledRedstoneProvider
      * handle this block.
      * @see dan200.computercraft.api.ComputerCraftAPI#registerBundledRedstoneProvider(IBundledRedstoneProvider)
      */
-    public int getBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side );
+    int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side );
 }

src/main/java/dan200/computercraft/api/turtle/ITurtleAccess.java

@@ -16,6 +16,9 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * The interface passed to turtle by turtles, providing methods that they can call.
  *
@@ -29,14 +32,16 @@ public interface ITurtleAccess
      *
      * @return the world in which the turtle resides.
      */
-    public World getWorld();
+    @Nonnull
+    World getWorld();
 
     /**
      * Returns a vector containing the integer co-ordinates at which the turtle resides.
      *
      * @return a vector containing the integer co-ordinates at which the turtle resides.
      */
-    public BlockPos getPosition();
+    @Nonnull
+    BlockPos getPosition();
 
     /**
      * Attempt to move this turtle to a new position.
@@ -51,7 +56,7 @@ public interface ITurtleAccess
      * {@link dan200.computercraft.api.permissions.ITurtlePermissionProvider#isBlockEnterable(World, BlockPos)}.
      * @throws UnsupportedOperationException When attempting to teleport on the client side.
      */
-    public boolean teleportTo( World world, BlockPos pos );
+    boolean teleportTo( @Nonnull World world, @Nonnull BlockPos pos );
 
     /**
      * Returns a vector containing the floating point co-ordinates at which the turtle is rendered.
@@ -61,7 +66,8 @@ public interface ITurtleAccess
      * @return A vector containing the floating point co-ordinates at which the turtle resides.
      * @see #getVisualYaw(float)
      */
-    public Vec3d getVisualPosition( float f );
+    @Nonnull
+    Vec3d getVisualPosition( float f );
 
     /**
      * Returns the yaw the turtle is facing when it is rendered.
@@ -70,7 +76,7 @@ public interface ITurtleAccess
      * @return The yaw the turtle is facing.
      * @see #getVisualPosition(float)
      */
-    public float getVisualYaw( float f );
+    float getVisualYaw( float f );
 
     /**
      * Returns the world direction the turtle is currently facing.
@@ -78,7 +84,8 @@ public interface ITurtleAccess
      * @return The world direction the turtle is currently facing.
      * @see #setDirection(EnumFacing)
      */
-    public EnumFacing getDirection();
+    @Nonnull
+    EnumFacing getDirection();
 
     /**
      * Set the direction the turtle is facing. Note that this will not play a rotation animation, you will also need to
@@ -87,7 +94,7 @@ public interface ITurtleAccess
      * @param dir The new direction to set. This should be on either the x or z axis (so north, south, east or west).
      * @see #getDirection()
      */
-    public void setDirection( EnumFacing dir );
+    void setDirection( @Nonnull EnumFacing dir );
 
     /**
      * Get the currently selected slot in the turtle's inventory.
@@ -96,7 +103,7 @@ public interface ITurtleAccess
      * @see #getInventory()
      * @see #setSelectedSlot(int)
      */
-    public int getSelectedSlot();
+    int getSelectedSlot();
 
     /**
      * Set the currently selected slot in the turtle's inventory.
@@ -107,7 +114,7 @@ public interface ITurtleAccess
      * @see #getInventory()
      * @see #getSelectedSlot()
      */
-    public void setSelectedSlot( int slot );
+    void setSelectedSlot( int slot );
 
     /**
      * Sets the colour of the turtle, as if the player had dyed it with a dye item.
@@ -116,7 +123,7 @@ public interface ITurtleAccess
      *                  the dye from the turtle.
      * @see #getDyeColour()
      */
-    public void setDyeColour( int dyeColour );
+    void setDyeColour( int dyeColour );
 
     /**
      * Gets the colour the turtle has been dyed.
@@ -125,14 +132,15 @@ public interface ITurtleAccess
      * is clean.
      * @see #getDyeColour()
      */
-    public int getDyeColour();
+    int getDyeColour();
 
     /**
      * Get the inventory of this turtle
      *
      * @return This turtle's inventory
      */
-    public IInventory getInventory();
+    @Nonnull
+    IInventory getInventory();
 
     /**
      * Determine whether this turtle will require fuel when performing actions.
@@ -141,7 +149,7 @@ public interface ITurtleAccess
      * @see #getFuelLevel()
      * @see #setFuelLevel(int)
      */
-    public boolean isFuelNeeded();
+    boolean isFuelNeeded();
 
     /**
      * Get the current fuel level of this turtle.
@@ -150,7 +158,7 @@ public interface ITurtleAccess
      * @see #isFuelNeeded()
      * @see #setFuelLevel(int)
      */
-    public int getFuelLevel();
+    int getFuelLevel();
 
     /**
      * Set the fuel level to a new value. It is generally preferred to use {@link #consumeFuel(int)}} or {@link #addFuel(int)}
@@ -162,14 +170,14 @@ public interface ITurtleAccess
      * @see #addFuel(int)
      * @see #consumeFuel(int)
      */
-    public void setFuelLevel( int fuel );
+    void setFuelLevel( int fuel );
 
     /**
      * Get the maximum amount of fuel a turtle can hold.
      *
      * @return The turtle's fuel limit.
      */
-    public int getFuelLimit();
+    int getFuelLimit();
 
     /**
      * Removes some fuel from the turtles fuel supply. Negative numbers can be passed in to INCREASE the fuel level of the turtle.
@@ -179,7 +187,7 @@ public interface ITurtleAccess
      * greater than the current fuel level of the turtle. No fuel will be consumed if {@code false} is returned.
      * @throws UnsupportedOperationException When attempting to consume fuel on the client side.
      */
-    public boolean consumeFuel( int fuel );
+    boolean consumeFuel( int fuel );
 
     /**
      * Increase the turtle's fuel level by the given amount.
@@ -187,7 +195,7 @@ public interface ITurtleAccess
      * @param fuel The amount to refuel with.
      * @throws UnsupportedOperationException When attempting to refuel on the client side.
      */
-    public void addFuel( int fuel );
+    void addFuel( int fuel );
 
     /**
      * Adds a custom command to the turtles command queue. Unlike peripheral methods, these custom commands will be executed
@@ -209,7 +217,8 @@ public interface ITurtleAccess
      * @see ITurtleCommand
      * @see ILuaContext#pullEvent(String)
      */
-    public Object[] executeCommand( ILuaContext context, ITurtleCommand command ) throws LuaException, InterruptedException;
+    @Nonnull
+    Object[] executeCommand( @Nonnull ILuaContext context, @Nonnull ITurtleCommand command ) throws LuaException, InterruptedException;
 
     /**
      * Start playing a specific animation. This will prevent other turtle commands from executing until
@@ -219,7 +228,7 @@ public interface ITurtleAccess
      * @throws UnsupportedOperationException When attempting to execute play an animation on the client side.
      * @see TurtleAnimation
      */
-    public void playAnimation( TurtleAnimation animation );
+    void playAnimation( @Nonnull TurtleAnimation animation );
 
     /**
      * Returns the turtle on the specified side of the turtle, if there is one.
@@ -228,7 +237,8 @@ public interface ITurtleAccess
      * @return The upgrade on the specified side of the turtle, if there is one.
      * @see #setUpgrade(TurtleSide, ITurtleUpgrade)
      */
-    public ITurtleUpgrade getUpgrade( TurtleSide side );
+    @Nullable
+    ITurtleUpgrade getUpgrade( @Nonnull TurtleSide side );
 
     /**
      * Set the upgrade for a given side, resetting peripherals and clearing upgrade specific data.
@@ -237,7 +247,7 @@ public interface ITurtleAccess
      * @param upgrade The upgrade to set, may be {@code null} to clear.
      * @see #getUpgrade(TurtleSide)
      */
-    public void setUpgrade( TurtleSide side, ITurtleUpgrade upgrade );
+    void setUpgrade( @Nonnull TurtleSide side, @Nullable ITurtleUpgrade upgrade );
 
     /**
      * Returns the peripheral created by the upgrade on the specified side of the turtle, if there is one.
@@ -245,7 +255,8 @@ public interface ITurtleAccess
      * @param side The side to get the peripheral from.
      * @return The peripheral created by the upgrade on the specified side of the turtle, {@code null} if none exists.
      */
-    public IPeripheral getPeripheral( TurtleSide side );
+    @Nullable
+    IPeripheral getPeripheral( @Nonnull TurtleSide side );
 
     /**
      * Get an upgrade-specific NBT compound, which can be used to store arbitrary data.
@@ -257,7 +268,8 @@ public interface ITurtleAccess
      * @return The upgrade-specific data.
      * @see #updateUpgradeNBTData(TurtleSide)
      */
-    public NBTTagCompound getUpgradeNBTData( TurtleSide side );
+    @Nonnull
+    NBTTagCompound getUpgradeNBTData( @Nullable TurtleSide side );
 
     /**
      * Mark the upgrade-specific data as dirty on a specific side. This is required for the data to be synced to the
@@ -266,5 +278,5 @@ public interface ITurtleAccess
      * @param side The side to mark dirty.
      * @see #updateUpgradeNBTData(TurtleSide)
      */
-    public void updateUpgradeNBTData( TurtleSide side );
+    void updateUpgradeNBTData( @Nonnull TurtleSide side );
 }

src/main/java/dan200/computercraft/api/turtle/ITurtleCommand.java

@@ -8,6 +8,8 @@ package dan200.computercraft.api.turtle;
 
 import dan200.computercraft.api.lua.ILuaContext;
 
+import javax.annotation.Nonnull;
+
 /**
  * An interface for objects executing custom turtle commands, used with {@link ITurtleAccess#executeCommand(ILuaContext, ITurtleCommand)}.
  *
@@ -28,5 +30,6 @@ public interface ITurtleCommand
      * @see TurtleCommandResult#failure(String)
      * @see TurtleCommandResult
      */
-    public TurtleCommandResult execute( ITurtleAccess turtle );
+    @Nonnull
+    TurtleCommandResult execute( @Nonnull ITurtleAccess turtle );
 }

src/main/java/dan200/computercraft/api/turtle/ITurtleUpgrade.java

@@ -17,6 +17,8 @@ import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.relauncher.SideOnly;
 import org.apache.commons.lang3.tuple.Pair;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import javax.vecmath.Matrix4f;
 
 
@@ -36,7 +38,8 @@ public interface ITurtleUpgrade
      * @return The unique ID for this upgrade.
      * @see ComputerCraftAPI#registerTurtleUpgrade(ITurtleUpgrade)
      */
-    public ResourceLocation getUpgradeID();
+    @Nonnull
+    ResourceLocation getUpgradeID();
 
     /**
      * Gets a numerical identifier representing this type of turtle upgrade,
@@ -47,7 +50,7 @@ public interface ITurtleUpgrade
      * @return The legacy ID, or -1 if is needed.
      * @see ComputerCraftAPI#registerTurtleUpgrade(ITurtleUpgrade)
      */
-    public int getLegacyUpgradeID();
+    int getLegacyUpgradeID();
 
     /**
      * Return an unlocalised string to describe this type of turtle in turtle item names.
@@ -56,7 +59,8 @@ public interface ITurtleUpgrade
      *
      * @return The localisation key for this upgrade's adjective.
      */
-    public String getUnlocalisedAdjective();
+    @Nonnull
+    String getUnlocalisedAdjective();
 
     /**
      * Return whether this turtle adds a tool or a peripheral to the turtle.
@@ -64,7 +68,8 @@ public interface ITurtleUpgrade
      * @return The type of upgrade this is.
      * @see TurtleUpgradeType for the differences between them.
      */
-    public TurtleUpgradeType getType();
+    @Nonnull
+    TurtleUpgradeType getType();
 
     /**
      * Return an item stack representing the type of item that a turtle must be crafted
@@ -73,7 +78,8 @@ public interface ITurtleUpgrade
      *
      * @return The item stack to craft with, or {@code null} if it cannot be crafted.
      */
-    public ItemStack getCraftingItem();
+    @Nullable
+    ItemStack getCraftingItem();
 
     /**
      * Will only be called for peripheral upgrades. Creates a peripheral for a turtle being placed using this upgrade.
@@ -87,7 +93,8 @@ public interface ITurtleUpgrade
      * @return The newly created peripheral. You may return {@code null} if this upgrade is a Tool
      * and this method is not expected to be called.
      */
-    public IPeripheral createPeripheral( ITurtleAccess turtle, TurtleSide side );
+    @Nullable
+    IPeripheral createPeripheral( @Nonnull ITurtleAccess turtle, @Nonnull TurtleSide side );
 
     /**
      * Will only be called for Tool turtle. Called when turtle.dig() or turtle.attack() is called
@@ -104,7 +111,8 @@ public interface ITurtleUpgrade
      * a swinging animation. You may return {@code null} if this turtle is a Peripheral  and this method is not expected
      * to be called.
      */
-    public TurtleCommandResult useTool( ITurtleAccess turtle, TurtleSide side, TurtleVerb verb, EnumFacing direction );
+    @Nonnull
+    TurtleCommandResult useTool( @Nonnull ITurtleAccess turtle, @Nonnull TurtleSide side, @Nonnull TurtleVerb verb, @Nonnull EnumFacing direction );
 
     /**
      * Called to obtain the model to be used when rendering a turtle peripheral.
@@ -119,7 +127,8 @@ public interface ITurtleUpgrade
      * a transformation of {@code null} has the same effect as the identify matrix.
      */
     @SideOnly(Side.CLIENT)
-    public Pair<IBakedModel, Matrix4f> getModel( ITurtleAccess turtle, TurtleSide side );
+    @Nonnull
+    Pair<IBakedModel, Matrix4f> getModel( @Nullable ITurtleAccess turtle, @Nonnull TurtleSide side );
 
     /**
      * Called once per tick for each turtle which has the upgrade equipped.
@@ -127,5 +136,5 @@ public interface ITurtleUpgrade
      * @param turtle Access to the turtle that the upgrade resides on.
      * @param side   Which side of the turtle (left or right) the upgrade resides on.
      */
-    public void update( ITurtleAccess turtle, TurtleSide side );
+    void update( @Nonnull ITurtleAccess turtle, @Nonnull TurtleSide side );
 }

src/main/java/dan200/computercraft/api/turtle/TurtleCommandResult.java

@@ -8,6 +8,9 @@ package dan200.computercraft.api.turtle;
 
 import net.minecraft.util.EnumFacing;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 /**
  * Used to indicate the result of executing a turtle command.
  *
@@ -24,6 +27,7 @@ public final class TurtleCommandResult
      *
      * @return A successful command result with no values.
      */
+    @Nonnull
     public static TurtleCommandResult success()
     {
         return success( null );
@@ -35,7 +39,8 @@ public final class TurtleCommandResult
      * @param results The results of executing this command.
      * @return A successful command result with the given values.
      */
-    public static TurtleCommandResult success( Object[] results )
+    @Nonnull
+    public static TurtleCommandResult success( @Nullable Object[] results )
     {
         if( results == null || results.length == 0 )
         {
@@ -52,6 +57,7 @@ public final class TurtleCommandResult
      *
      * @return A failed command result with no message.
      */
+    @Nonnull
     public static TurtleCommandResult failure()
     {
         return failure( null );
@@ -63,7 +69,8 @@ public final class TurtleCommandResult
      * @param errorMessage The error message to provide.
      * @return A failed command result with a message.
      */
-    public static TurtleCommandResult failure( String errorMessage )
+    @Nonnull
+    public static TurtleCommandResult failure( @Nullable String errorMessage )
     {
         if( errorMessage == null )
         {
@@ -101,6 +108,7 @@ public final class TurtleCommandResult
      *
      * @return The command's error message, or {@code null} if it was a success.
      */
+    @Nullable
     public String getErrorMessage()
     {
         return m_errorMessage;
@@ -111,6 +119,7 @@ public final class TurtleCommandResult
      *
      * @return The command's result, or {@code null} if it was a failure.
      */
+    @Nullable
     public Object[] getResults()
     {
         return m_results;

src/main/java/dan200/computercraft/client/gui/FixedWidthFontRenderer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/GuiComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/GuiConfigCC.java

@@ -18,7 +18,7 @@ public class GuiConfigCC extends GuiConfig
 {
     public GuiConfigCC( GuiScreen parentScreen )
     {
-        super( parentScreen, getConfigElements(), "ComputerCraft", false, false, "ComputerCraft" );
+        super( parentScreen, getConfigElements(), ComputerCraft.MOD_ID, false, false, "ComputerCraft" );
     }
 
     private static List<IConfigElement> getConfigElements()

src/main/java/dan200/computercraft/client/gui/GuiDiskDrive.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/GuiPocketComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/GuiPrinter.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/GuiPrintout.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -15,7 +15,6 @@ import net.minecraft.client.gui.inventory.GuiContainer;
 import net.minecraft.client.renderer.GlStateManager;
 import net.minecraft.util.ResourceLocation;
 import org.lwjgl.input.Mouse;
-import org.lwjgl.opengl.GL11;
 
 import java.io.IOException;
 

src/main/java/dan200/computercraft/client/gui/GuiTurtle.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/widgets/MousePos.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/gui/widgets/Widget.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -11,13 +11,10 @@ import net.minecraft.client.audio.PositionedSoundRecord;
 import net.minecraft.client.gui.FontRenderer;
 import net.minecraft.client.gui.Gui;
 import net.minecraft.client.renderer.*;
-import net.minecraft.client.renderer.RenderItem;
 import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
 import net.minecraft.init.SoundEvents;
 import net.minecraft.item.ItemStack;
-import net.minecraft.util.ResourceLocation;
 import org.lwjgl.opengl.GL11;
-import org.lwjgl.opengl.GL12;
 
 public abstract class Widget extends Gui
 {
@@ -269,9 +266,8 @@ public abstract class Widget extends Gui
         FontRenderer fontRenderer = mc.fontRendererObj;
 
         int width = 0;
-        for( int i=0; i<lines.length; ++i )
+        for( String line : lines )
         {
-            String line = lines[i];
             width = Math.max( fontRenderer.getStringWidth( line ), width );
         }
         int startX = x + 12;

src/main/java/dan200/computercraft/client/gui/widgets/WidgetContainer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -48,10 +48,10 @@ public class WidgetContainer extends Widget
 	@Override
 	public void update()
 	{
-		for( int i=0; i<m_widgets.size(); ++i )
+        for( Widget m_widget : m_widgets )
-		{
+        {
-			m_widgets.get( i ).update();
+            m_widget.update();
-		}
+        }
 		if( m_modalWidget != null )
 		{
 			m_modalWidget.update();
@@ -61,20 +61,19 @@ public class WidgetContainer extends Widget
 	@Override
 	public void draw( Minecraft mc, int xOrigin, int yOrigin, int mouseX, int mouseY )
 	{
-		for( int i=0; i<m_widgets.size(); ++i )
+        for( Widget widget : m_widgets )
-		{
+        {
-			Widget widget = m_widgets.get( i );
+            if( widget.isVisible() )
-			if( widget.isVisible() )
+            {
-			{
+                widget.draw(
-				widget.draw(
+                    mc,
-						mc,
+                    xOrigin + getXPosition(),
-						xOrigin + getXPosition(),
+                    yOrigin + getYPosition(),
-						yOrigin + getYPosition(),
+                    (m_modalWidget == null) ? (mouseX - getXPosition()) : -99,
-						(m_modalWidget == null) ? (mouseX - getXPosition()) : -99,
+                    (m_modalWidget == null) ? (mouseY - getYPosition()) : -99
-						(m_modalWidget == null) ? (mouseY - getYPosition()) : -99
+                );
-				);
+            }
-			}
+        }
-		}
 		if( m_modalWidget != null )
 		{
 			if( m_modalWidget.isVisible() )
@@ -102,20 +101,19 @@ public class WidgetContainer extends Widget
 	@Override
 	public void drawForeground( Minecraft mc, int xOrigin, int yOrigin, int mouseX, int mouseY )
 	{
-		for( int i=0; i<m_widgets.size(); ++i )
+        for( Widget widget : m_widgets )
-		{
+        {
-			Widget widget = m_widgets.get( i );
+            if( widget.isVisible() )
-			if( widget.isVisible() )
+            {
-			{
+                widget.drawForeground(
-				widget.drawForeground(
+                    mc,
-						mc,
+                    xOrigin + getXPosition(),
-						xOrigin + getXPosition(),
+                    yOrigin + getYPosition(),
-						yOrigin + getYPosition(),
+                    (m_modalWidget == null) ? (mouseX - getXPosition()) : -99,
-						(m_modalWidget == null) ? (mouseX - getXPosition()) : -99,
+                    (m_modalWidget == null) ? (mouseY - getYPosition()) : -99
-						(m_modalWidget == null) ? (mouseY - getYPosition()) : -99
+                );
-				);
+            }
-			}
+        }
-		}
 
 		if( m_modalWidget != null )
 		{
@@ -148,14 +146,13 @@ public class WidgetContainer extends Widget
 		pos.y -= getYPosition();
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    widget.modifyMousePosition( pos );
-					widget.modifyMousePosition( pos );
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -173,23 +170,22 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    if( widget.suppressItemTooltips(
-					if( widget.suppressItemTooltips(
+                        mc,
-							mc,
+                        xOrigin + getXPosition(),
-							xOrigin + getXPosition(),
+                        yOrigin + getYPosition(),
-							yOrigin + getYPosition(),
+                        mouseX - getXPosition(),
-							mouseX - getXPosition(),
+                        mouseY - getYPosition()
-							mouseY - getYPosition()
+                    ) )
-					) )
+                    {
-					{
+                        return true;
-						return true;
+                    }
-					}
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -211,17 +207,16 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    if( widget.suppressKeyPress( c, k ) )
-					if( widget.suppressKeyPress( c, k ) )
+                    {
-					{
+                        return true;
-						return true;
+                    }
-					}
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -241,17 +236,16 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    widget.handleMouseInput(
-					widget.handleMouseInput(
+                        mouseX - getXPosition(),
-							mouseX - getXPosition(),
+                        mouseY - getYPosition()
-							mouseY - getYPosition()
+                    );
-					);
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -270,14 +264,13 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    widget.handleKeyboardInput();
-					widget.handleKeyboardInput();
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -293,18 +286,17 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    widget.mouseClicked(
-					widget.mouseClicked(
+                        mouseX - getXPosition(),
-							mouseX - getXPosition(),
+                        mouseY - getYPosition(),
-							mouseY - getYPosition(),
+                        mouseButton
-							mouseButton
+                    );
-					);
+                }
-				}
+            }
-			}
 		}
 		else
 		{
@@ -324,14 +316,13 @@ public class WidgetContainer extends Widget
 	{
 		if( m_modalWidget == null )
 		{
-			for( int i = 0; i < m_widgets.size(); ++i )
+            for( Widget widget : m_widgets )
-			{
+            {
-				Widget widget = m_widgets.get( i );
+                if( widget.isVisible() )
-				if( widget.isVisible() )
+                {
-				{
+                    widget.keyTyped( c, k );
-					widget.keyTyped( c, k );
+                }
-				}
+            }
-			}
 		}
 		else
 		{

src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/client/proxy/CCTurtleProxyClient.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -38,6 +38,8 @@ import net.minecraftforge.fml.client.registry.ClientRegistry;
 import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent;
 
+import javax.annotation.Nonnull;
+
 public class CCTurtleProxyClient extends CCTurtleProxyCommon
 {
     public CCTurtleProxyClient()
@@ -56,8 +58,9 @@ public class CCTurtleProxyClient extends CCTurtleProxyCommon
         {
             private ModelResourceLocation turtle_dynamic = new ModelResourceLocation( "computercraft:turtle_dynamic", "inventory" );
 
+            @Nonnull
             @Override
-            public ModelResourceLocation getModelLocation( ItemStack stack )
+            public ModelResourceLocation getModelLocation( @Nonnull ItemStack stack )
             {
                 return turtle_dynamic;
             }
@@ -188,7 +191,7 @@ public class CCTurtleProxyClient extends CCTurtleProxyCommon
     private static class TurtleItemColour implements IItemColor
     {
         @Override
-        public int getColorFromItemstack( ItemStack stack, int tintIndex )
+        public int getColorFromItemstack( @Nonnull ItemStack stack, int tintIndex )
         {
             if( tintIndex == 0 )
             {

src/main/java/dan200/computercraft/client/proxy/ComputerCraftProxyClient.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -49,12 +49,12 @@ import net.minecraftforge.client.event.RenderPlayerEvent;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.fml.client.FMLClientHandler;
 import net.minecraftforge.fml.client.registry.ClientRegistry;
-import net.minecraftforge.fml.common.FMLCommonHandler;
 import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
 import net.minecraftforge.fml.common.gameevent.TickEvent;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.relauncher.SideOnly;
 
+import javax.annotation.Nonnull;
 import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
@@ -88,8 +88,9 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
             private ModelResourceLocation computer = new ModelResourceLocation( "computercraft:CC-Computer", "inventory" );
             private ModelResourceLocation advanced_computer = new ModelResourceLocation( "computercraft:advanced_computer", "inventory" );
 
+            @Nonnull
             @Override
-            public ModelResourceLocation getModelLocation( ItemStack stack )
+            public ModelResourceLocation getModelLocation( @Nonnull ItemStack stack )
             {
                 ItemComputer itemComputer = (ItemComputer) stack.getItem();
                 ComputerFamily family = itemComputer.getFamily( stack.getItemDamage() );
@@ -121,8 +122,9 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
             private ModelResourceLocation advanced_pocket_computer_on = new ModelResourceLocation( "computercraft:advanced_pocket_computer_on", "inventory" );
             private ModelResourceLocation advanced_pocket_computer_blinking = new ModelResourceLocation( "computercraft:advanced_pocket_computer_blinking", "inventory" );
 
+            @Nonnull
             @Override
-            public ModelResourceLocation getModelLocation( ItemStack stack )
+            public ModelResourceLocation getModelLocation( @Nonnull ItemStack stack )
             {
                 ItemPocketComputer itemPocketComputer = (ItemPocketComputer)stack.getItem();
                 switch( itemPocketComputer.getFamily( stack ) )
@@ -180,7 +182,7 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
         mc.getItemColors().registerItemColorHandler( new IItemColor()
         {
             @Override
-            public int getColorFromItemstack( ItemStack stack, int layout )
+            public int getColorFromItemstack( @Nonnull ItemStack stack, int layout )
             {
                 if( layout != 1 ) return 0xFFFFFF;
 
@@ -219,8 +221,9 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
         ModelBakery.registerItemVariants( item, new ResourceLocation( "computercraft", name ) );
         Minecraft.getMinecraft().getRenderItem().getItemModelMesher().register( item, new ItemMeshDefinition()
         {
+            @Nonnull
             @Override
-            public ModelResourceLocation getModelLocation( ItemStack stack )
+            public ModelResourceLocation getModelLocation( @Nonnull ItemStack stack )
             {
                 return res;
             }
@@ -276,10 +279,10 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
     @Override
     public String getRecordInfo( ItemStack recordStack )
     {
-        List info = new ArrayList(1);
+        List<String> info = new ArrayList<String>( 1 );
         recordStack.getItem().addInformation( recordStack, null, info, false );
         if( info.size() > 0 ) {
-            return info.get(0).toString();
+            return info.get( 0 );
         } else {
             return super.getRecordInfo( recordStack );
         }
@@ -401,7 +404,7 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
                 {
                     ComputerCraft.clientComputerRegistry.add( instanceID, new ClientComputer( instanceID ) );
                 }
-                ComputerCraft.clientComputerRegistry.get( instanceID ).handlePacket( packet, (EntityPlayer) player );
+                ComputerCraft.clientComputerRegistry.get( instanceID ).handlePacket( packet, player );
                 break;
             }
             case ComputerCraftPacket.ComputerDeleted:
@@ -519,7 +522,7 @@ public class ComputerCraftProxyClient extends ComputerCraftProxyCommon
 		}
 
 		@Override
-		public int getColorFromItemstack(ItemStack stack, int layer)
+		public int getColorFromItemstack( @Nonnull ItemStack stack, int layer)
 		{
 			return layer == 0 ? 0xFFFFFF : disk.getColor(stack);
 		}

src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -25,6 +25,8 @@ import net.minecraft.util.EnumFacing;
 import net.minecraft.util.math.BlockPos;
 import org.lwjgl.opengl.GL11;
 
+import javax.annotation.Nonnull;
+
 public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMonitor>
 {
     public TileEntityMonitorRenderer()
@@ -32,7 +34,7 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
     }
 
     @Override
-    public void renderTileEntityAt( TileMonitor tileEntity, double posX, double posY, double posZ, float f, int i )
+    public void renderTileEntityAt( @Nonnull TileMonitor tileEntity, double posX, double posY, double posZ, float f, int i )
     {
         if( tileEntity != null )
         {

src/main/java/dan200/computercraft/client/render/TileEntityTurtleRenderer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -41,6 +41,7 @@ import net.minecraftforge.client.model.pipeline.LightUtil;
 import org.apache.commons.lang3.tuple.Pair;
 import org.lwjgl.opengl.GL11;
 
+import javax.annotation.Nonnull;
 import javax.vecmath.Matrix4f;
 import java.util.List;
 
@@ -75,7 +76,7 @@ public class TileEntityTurtleRenderer extends TileEntitySpecialRenderer<TileTurt
     }
 
     @Override
-    public void renderTileEntityAt( TileTurtle tileEntity, double posX, double posY, double posZ, float f, int i )
+    public void renderTileEntityAt( @Nonnull TileTurtle tileEntity, double posX, double posY, double posZ, float f, int i )
     {
         if( tileEntity != null )
         {

src/main/java/dan200/computercraft/client/render/TurtleMultiModel.java

@@ -10,6 +10,7 @@ import net.minecraft.client.renderer.vertex.VertexFormat;
 import net.minecraft.client.renderer.vertex.VertexFormatElement;
 import net.minecraft.util.EnumFacing;
 
+import javax.annotation.Nonnull;
 import javax.vecmath.Matrix4f;
 import javax.vecmath.Point3f;
 import java.util.ArrayList;
@@ -24,7 +25,7 @@ public class TurtleMultiModel implements IBakedModel
     private IBakedModel m_rightUpgradeModel;
     private Matrix4f m_rightUpgradeTransform;
     private List<BakedQuad> m_generalQuads;
-    private List<BakedQuad> m_faceQuads[];
+    private List<BakedQuad>[] m_faceQuads;
 
     public TurtleMultiModel( IBakedModel baseModel, IBakedModel overlayModel, IBakedModel leftUpgradeModel, Matrix4f leftUpgradeTransform, IBakedModel rightUpgradeModel, Matrix4f rightUpgradeTransform )
     {
@@ -39,6 +40,7 @@ public class TurtleMultiModel implements IBakedModel
         m_faceQuads = new List[6];
     }
 
+    @Nonnull
     @Override
     public List<BakedQuad> getQuads( IBlockState state, EnumFacing side, long rand )
     {
@@ -107,18 +109,22 @@ public class TurtleMultiModel implements IBakedModel
         return m_baseModel.isBuiltInRenderer();
     }
 
+    @Nonnull
     @Override
     public TextureAtlasSprite getParticleTexture()
     {
         return m_baseModel.getParticleTexture();
     }
 
+    @Nonnull
     @Override
+    @Deprecated
     public ItemCameraTransforms getItemCameraTransforms()
     {
         return m_baseModel.getItemCameraTransforms();
     }
 
+    @Nonnull
     @Override
     public ItemOverrideList getOverrides()
     {
@@ -134,9 +140,8 @@ public class TurtleMultiModel implements IBakedModel
         else
         {
             List<BakedQuad> output = new ArrayList<BakedQuad>( input.size() );
-            for( int i=0; i<input.size(); ++i )
+            for( BakedQuad quad : input )
             {
-                BakedQuad quad = input.get( i );
                 output.add( transformQuad( quad, transform ) );
             }
             return output;

src/main/java/dan200/computercraft/client/render/TurtleSmartItemModel.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -26,10 +26,9 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.world.World;
-import net.minecraftforge.client.model.IModel;
-import net.minecraftforge.client.model.ISmartVariant;
 import org.apache.commons.lang3.tuple.Pair;
 
+import javax.annotation.Nonnull;
 import javax.vecmath.Matrix4f;
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -102,8 +101,9 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
         m_cachedModels = new HashMap<TurtleModelCombination, IBakedModel>();
         m_overrides = new ItemOverrideList( new ArrayList<ItemOverride>() )
         {
+            @Nonnull
             @Override
-            public IBakedModel handleItemState(IBakedModel originalModel, ItemStack stack, World world, EntityLivingBase entity)
+            public IBakedModel handleItemState( @Nonnull IBakedModel originalModel, ItemStack stack, @Nonnull World world, @Nonnull EntityLivingBase entity)
             {
                 ItemTurtleBase turtle = (ItemTurtleBase) stack.getItem();
                 ComputerFamily family = turtle.getFamily( stack );
@@ -127,6 +127,7 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
         };
     }
 
+    @Nonnull
     @Override
     public ItemOverrideList getOverrides()
     {
@@ -134,7 +135,7 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
     }
 
     @Override
-    public void onResourceManagerReload( IResourceManager resourceManager )
+    public void onResourceManagerReload( @Nonnull IResourceManager resourceManager )
     {
         m_cachedModels.clear();
     }
@@ -173,6 +174,7 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
 
     // These should not be called:
 
+    @Nonnull
     @Override
     public List<BakedQuad> getQuads( IBlockState state, EnumFacing facing, long rand )
     {
@@ -197,13 +199,16 @@ public class TurtleSmartItemModel implements IBakedModel, IResourceManagerReload
         return getDefaultModel().isBuiltInRenderer();
     }
 
+    @Nonnull
     @Override
     public TextureAtlasSprite getParticleTexture()
     {
         return getDefaultModel().getParticleTexture();
     }
 
+    @Nonnull
     @Override
+    @Deprecated
     public ItemCameraTransforms getItemCameraTransforms()
     {
         return getDefaultModel().getItemCameraTransforms();

src/main/java/dan200/computercraft/core/apis/BitAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,6 +9,8 @@ package dan200.computercraft.core.apis;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 
+import javax.annotation.Nonnull;
+
 // Contributed by Nia
 // Based on LuaBit (http://luaforge.net/projects/bit)
  
@@ -68,6 +70,7 @@ public class BitAPI implements ILuaAPI
     {
     }
     
+    @Nonnull
     @Override
     public String[] getMethodNames() {
         return new String[] {
@@ -77,7 +80,7 @@ public class BitAPI implements ILuaAPI
     }
     
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         Object a = args.length>0?args[0]:null;
         Object b = args.length>1?args[1]:null;

src/main/java/dan200/computercraft/core/apis/BufferAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -11,6 +11,8 @@ import dan200.computercraft.api.lua.ILuaObject;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.terminal.TextBuffer;
 
+import javax.annotation.Nonnull;
+
 public class BufferAPI implements ILuaAPI
 {
     private static class BufferLuaObject implements ILuaObject
@@ -22,6 +24,7 @@ public class BufferAPI implements ILuaAPI
             m_buffer = buffer;
         }
 
+        @Nonnull
         @Override
         public String[] getMethodNames()
         {
@@ -35,7 +38,7 @@ public class BufferAPI implements ILuaAPI
         }
 
         @Override
-        public Object[] callMethod( ILuaContext context, int method, Object[] arguments ) throws LuaException, InterruptedException
+        public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException
         {
             switch( method )
             {
@@ -165,6 +168,7 @@ public class BufferAPI implements ILuaAPI
     {
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -174,7 +178,7 @@ public class BufferAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] arguments ) throws LuaException, InterruptedException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException
     {
         switch( method )
         {

src/main/java/dan200/computercraft/core/apis/FSAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -14,6 +14,7 @@ import dan200.computercraft.core.filesystem.FileSystemException;
 import dan200.computercraft.core.filesystem.IMountedFileBinary;
 import dan200.computercraft.core.filesystem.IMountedFileNormal;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
@@ -54,6 +55,7 @@ public class FSAPI implements ILuaAPI
         m_fileSystem = null;
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -78,7 +80,7 @@ public class FSAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
         {
@@ -122,7 +124,7 @@ public class FSAPI implements ILuaAPI
                     throw new LuaException( "Expected string" );
                 }
                 String path = (String)args[0];
-                return new Object[]{ m_fileSystem.getName( path ) };
+                return new Object[]{ FileSystem.getName( path ) };
             }
             case 3:
             {
@@ -357,7 +359,7 @@ public class FSAPI implements ILuaAPI
                     throw new LuaException( "Expected string" );
                 }
                 String path = (String)args[0];
-                return new Object[]{ m_fileSystem.getDirectory( path ) };
+                return new Object[]{ FileSystem.getDirectory( path ) };
             }
             default:
             {
@@ -370,6 +372,7 @@ public class FSAPI implements ILuaAPI
     private static Object[] wrapBufferedReader( final IMountedFileNormal reader )
     {
         return new Object[] { new ILuaObject() {
+            @Nonnull
             @Override
             public String[] getMethodNames()
             {
@@ -381,7 +384,7 @@ public class FSAPI implements ILuaAPI
             }
             
             @Override
-            public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+            public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
             {
                 switch( method )
                 {
@@ -439,6 +442,7 @@ public class FSAPI implements ILuaAPI
     private static Object[] wrapBufferedWriter( final IMountedFileNormal writer )
     {
         return new Object[] { new ILuaObject() {
+            @Nonnull
             @Override
             public String[] getMethodNames()
             {
@@ -451,7 +455,7 @@ public class FSAPI implements ILuaAPI
             }
             
             @Override
-            public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+            public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
             {
                 switch( method )
                 {
@@ -521,6 +525,7 @@ public class FSAPI implements ILuaAPI
         
         return new Object[] { new ILuaObject() {
 
+            @Nonnull
             @Override
             public String[] getMethodNames() {
                 return new String[] {
@@ -530,7 +535,7 @@ public class FSAPI implements ILuaAPI
             }
 
             @Override
-            public Object[] callMethod( ILuaContext context, int method, Object[] args) throws LuaException {
+            public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args) throws LuaException {
                 switch( method )
                 {
                     case 0:
@@ -572,6 +577,7 @@ public class FSAPI implements ILuaAPI
         
         return new Object[] { new ILuaObject() {
 
+            @Nonnull
             @Override
             public String[] getMethodNames() {
                 return new String[] {
@@ -582,7 +588,7 @@ public class FSAPI implements ILuaAPI
             }
 
             @Override
-            public Object[] callMethod( ILuaContext context, int method, Object[] args) throws LuaException {
+            public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args) throws LuaException {
                 switch( method )
                 {
                     case 0:

src/main/java/dan200/computercraft/core/apis/HTTPAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,14 +10,15 @@ import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.ILuaObject;
 import dan200.computercraft.api.lua.LuaException;
 
+import javax.annotation.Nonnull;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.util.*;
 
 public class HTTPAPI implements ILuaAPI
 {
-    private IAPIEnvironment m_apiEnvironment;
+    private final IAPIEnvironment m_apiEnvironment;
-    private List<HTTPRequest> m_httpRequests;
+    private final List<HTTPRequest> m_httpRequests;
     
     public HTTPAPI( IAPIEnvironment environment )
     {
@@ -72,6 +73,7 @@ public class HTTPAPI implements ILuaAPI
     private static ILuaObject wrapBufferedReader( final BufferedReader reader, final int responseCode, final Map<String, String> responseHeaders )
     {
         return new ILuaObject() {
+            @Nonnull
             @Override
             public String[] getMethodNames()
             {
@@ -85,7 +87,7 @@ public class HTTPAPI implements ILuaAPI
             }
             
             @Override
-            public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+            public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
             {
                 switch( method )
                 {
@@ -155,15 +157,15 @@ public class HTTPAPI implements ILuaAPI
     {
         synchronized( m_httpRequests )
         {
-            Iterator<HTTPRequest> it = m_httpRequests.iterator();
+            for( HTTPRequest r : m_httpRequests )
-            while( it.hasNext() ) {
+            {
-                HTTPRequest r = it.next();
                 r.cancel();
             }
             m_httpRequests.clear();
         }
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -174,7 +176,7 @@ public class HTTPAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
         {
@@ -199,7 +201,7 @@ public class HTTPAPI implements ILuaAPI
                 Map<String, String> headers = null;
                 if( args.length >= 3 && args[2] instanceof Map )
                 {
-                    Map table = (Map)args[2];
+                    Map<?, ?> table = (Map<?, ?>)args[2];
                     headers = new HashMap<String, String>( table.size() );
                     for( Object key : table.keySet() )
                     {

src/main/java/dan200/computercraft/core/apis/HTTPRequest.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -18,12 +18,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.regex.Pattern;
 
-class HTTPRequestException extends Exception {
-    public HTTPRequestException( String s ) {
-        super( s );
-    }
-}
-
 public class HTTPRequest
 {
     public static URL checkURL( String urlString ) throws HTTPRequestException
@@ -49,9 +43,8 @@ public class HTTPRequest
         boolean allowed = false;
         String whitelistString = ComputerCraft.http_whitelist;
         String[] allowedURLs = whitelistString.split( ";" );
-        for( int i=0; i<allowedURLs.length; ++i )
+        for( String allowedURL : allowedURLs )
         {
-            String allowedURL = allowedURLs[i];
             Pattern allowedURLPattern = Pattern.compile( "^\\Q" + allowedURL.replaceAll( "\\*", "\\\\E.*\\\\Q" ) + "\\E$" );
             if( allowedURLPattern.matcher( url.getHost() ).matches() )
             {
@@ -274,7 +267,7 @@ public class HTTPRequest
     
     public BufferedReader getContents()
     {
-        String result = null;
+        String result;
         synchronized(m_lock) {
             result = m_result;
         }
@@ -285,8 +278,8 @@ public class HTTPRequest
         return null;
     }
     
-    private Object m_lock = new Object();
+    private final Object m_lock = new Object();
-    private URL m_url;
+    private final URL m_url;
     private final String m_urlString;
     
     private boolean m_complete;

src/main/java/dan200/computercraft/core/apis/HTTPRequestException.java

@@ -0,0 +1,11 @@
+package dan200.computercraft.core.apis;
+
+public class HTTPRequestException extends Exception
+{
+    private static final long serialVersionUID = 7591208619422744652L;
+
+    public HTTPRequestException( String s )
+    {
+        super( s );
+    }
+}

src/main/java/dan200/computercraft/core/apis/IAPIEnvironment.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -14,32 +14,32 @@ import dan200.computercraft.core.terminal.Terminal;
 
 public interface IAPIEnvironment
 {
-    public static interface IPeripheralChangeListener
+    interface IPeripheralChangeListener
     {
-        public void onPeripheralChanged( int side, IPeripheral newPeripheral );
+        void onPeripheralChanged( int side, IPeripheral newPeripheral );
     }
     
-    public Computer getComputer();
+    Computer getComputer();
-    public int getComputerID();
+    int getComputerID();
-    public IComputerEnvironment getComputerEnvironment();
+    IComputerEnvironment getComputerEnvironment();
-    public Terminal getTerminal();
+    Terminal getTerminal();
-    public FileSystem getFileSystem();
+    FileSystem getFileSystem();
     
-    public void shutdown();
+    void shutdown();
-    public void reboot();
+    void reboot();
-    public void queueEvent( String event, Object[] args );
+    void queueEvent( String event, Object[] args );
 
-    public void setOutput( int side, int output );
+    void setOutput( int side, int output );
-    public int getOutput( int side );
+    int getOutput( int side );
-    public int getInput( int side );
+    int getInput( int side );
 
-    public void setBundledOutput( int side, int output );
+    void setBundledOutput( int side, int output );
-    public int getBundledOutput( int side );
+    int getBundledOutput( int side );
-    public int getBundledInput( int side );
+    int getBundledInput( int side );
     
-    public void setPeripheralChangeListener( IPeripheralChangeListener listener );
+    void setPeripheralChangeListener( IPeripheralChangeListener listener );
-    public IPeripheral getPeripheral( int side );
+    IPeripheral getPeripheral( int side );
 
-    public String getLabel();
+    String getLabel();
-    public void setLabel( String label );
+    void setLabel( String label );
 }

src/main/java/dan200/computercraft/core/apis/ILuaAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,9 +9,9 @@ import dan200.computercraft.api.lua.ILuaObject;
 
 public interface ILuaAPI extends ILuaObject
 {
-    public String[] getNames();
+    String[] getNames();
 
-    public void startup(); // LT
+    void startup(); // LT
-    public void advance( double _dt ); // MT
+    void advance( double _dt ); // MT
-    public void shutdown(); // LT
+    void shutdown(); // LT
 }

src/main/java/dan200/computercraft/core/apis/OSAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,6 +10,7 @@ import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.shared.util.StringUtil;
 
+import javax.annotation.Nonnull;
 import java.util.*;
 
 public class OSAPI implements ILuaAPI
@@ -47,7 +48,7 @@ public class OSAPI implements ILuaAPI
         }
 
         @Override
-        public int compareTo( Alarm o )
+        public int compareTo( @Nonnull Alarm o )
         {
             double t = (double)m_day * 24.0 + m_time;
             double ot = (double)m_day * 24.0 + m_time;
@@ -166,6 +167,7 @@ public class OSAPI implements ILuaAPI
         }
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -216,7 +218,7 @@ public class OSAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
         {

src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -18,6 +18,7 @@ import dan200.computercraft.core.computer.ITask;
 import dan200.computercraft.core.filesystem.FileSystem;
 import dan200.computercraft.core.filesystem.FileSystemException;
 
+import javax.annotation.Nonnull;
 import java.util.*;
 
 public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChangeListener
@@ -88,9 +89,9 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             m_attached = false;
             
             // Unmount everything the detach function forgot to do
-            Iterator<String> it = m_mounts.iterator();
+            for( String m_mount : m_mounts )
-            while( it.hasNext() ) {
+            {
-                m_fileSystem.unmount( it.next() );
+                m_fileSystem.unmount( m_mount );
             }
             m_mounts.clear();
         }
@@ -118,13 +119,13 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         // IComputerAccess implementation
 
         @Override
-        public String mount( String desiredLoc, IMount mount )
+        public String mount( @Nonnull String desiredLoc, @Nonnull IMount mount )
         {
             return mount( desiredLoc, mount, m_side );
         }
 
         @Override
-        public synchronized String mount( String desiredLoc, IMount mount, String driveName )
+        public synchronized String mount( @Nonnull String desiredLoc, @Nonnull IMount mount, @Nonnull String driveName )
         {
             if( !m_attached )
             {
@@ -132,7 +133,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             }
             
             // Mount the location
-            String location = null;
+            String location;
             synchronized( m_fileSystem )
             {
                 location = findFreeLocation( desiredLoc );
@@ -153,13 +154,13 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
 
         @Override
-        public String mountWritable( String desiredLoc, IWritableMount mount )
+        public String mountWritable( @Nonnull String desiredLoc, @Nonnull IWritableMount mount )
         {
             return mountWritable( desiredLoc, mount, m_side );
         }
 
         @Override
-        public synchronized String mountWritable( String desiredLoc, IWritableMount mount, String driveName )
+        public synchronized String mountWritable( @Nonnull String desiredLoc, @Nonnull IWritableMount mount, @Nonnull String driveName )
         {
             if( !m_attached )
             {
@@ -167,7 +168,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             }
             
             // Mount the location
-            String location = null;
+            String location;
             synchronized( m_fileSystem )
             {
                 location = findFreeLocation( desiredLoc );
@@ -215,7 +216,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
                 
         @Override
-        public synchronized void queueEvent( final String event, final Object[] arguments )
+        public synchronized void queueEvent( @Nonnull final String event, final Object[] arguments )
         {
             if( !m_attached ) {
                 throw new RuntimeException( "You are not attached to this Computer" );
@@ -223,6 +224,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             m_environment.queueEvent( event, arguments );
         }
         
+        @Nonnull
         @Override
         public synchronized String getAttachmentName()
         {
@@ -233,9 +235,9 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
     }
     
-    private IAPIEnvironment m_environment;
+    private final IAPIEnvironment m_environment;
     private FileSystem m_fileSystem;
-    private PeripheralWrapper[] m_peripherals;
+    private final PeripheralWrapper[] m_peripherals;
     private boolean m_running;
 
     public PeripheralAPI( IAPIEnvironment _environment )
@@ -372,6 +374,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         }
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -384,7 +387,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException, InterruptedException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException, InterruptedException
     {
         switch( method )
         {
@@ -467,15 +470,14 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                 int side = parseSide( args );
                 if( side >= 0 )
                 {
-                    PeripheralWrapper p = null;
+                    PeripheralWrapper p;
                     synchronized( m_peripherals )
                     {
                         p = m_peripherals[ side ];
                     }
                     if( p != null )
                     {
-                        Object[] results = p.call( context, methodName, methodArgs );
+                        return p.call( context, methodName, methodArgs );
-                        return results;
                     }
                 }
                 throw new LuaException( "No peripheral attached" );

src/main/java/dan200/computercraft/core/apis/RedstoneAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,6 +10,7 @@ import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 import dan200.computercraft.core.computer.Computer;
 
+import javax.annotation.Nonnull;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -45,6 +46,7 @@ public class RedstoneAPI implements ILuaAPI
     {
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -67,7 +69,7 @@ public class RedstoneAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
         {
@@ -89,7 +91,7 @@ public class RedstoneAPI implements ILuaAPI
                     throw new LuaException( "Expected string, boolean" );
                 }
                 int side = parseSide( args );
-                boolean output = ((Boolean)args[1]).booleanValue();
+                boolean output = (Boolean) args[ 1 ];
                 m_environment.setOutput( side, output ? 15 : 0 );
                 return null;
             }

src/main/java/dan200/computercraft/core/apis/TermAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -17,6 +17,8 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 
+import javax.annotation.Nonnull;
+
 public class TermAPI implements ILuaAPI
 {
     private final Terminal m_terminal;
@@ -51,6 +53,7 @@ public class TermAPI implements ILuaAPI
     {
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -117,7 +120,7 @@ public class TermAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] args ) throws LuaException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
         {

src/main/java/dan200/computercraft/core/computer/Computer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -21,7 +21,6 @@ import dan200.computercraft.core.terminal.Terminal;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.List;
 
 public class Computer
@@ -30,7 +29,7 @@ public class Computer
         "bottom", "top", "back", "front", "right", "left",
     };
     
-    private static enum State
+    private enum State
     {
         Off,
         Starting,
@@ -187,26 +186,26 @@ public class Computer
     private boolean m_blinking;
 
     private ILuaMachine m_machine;
-    private List<ILuaAPI> m_apis;
+    private final List<ILuaAPI> m_apis;
-    private APIEnvironment m_apiEnvironment;
+    private final APIEnvironment m_apiEnvironment;
     
-    private Terminal m_terminal;
+    private final Terminal m_terminal;
     private FileSystem m_fileSystem;
     private IWritableMount m_rootMount;
 
-    private int[] m_internalOutput;
+    private final int[] m_internalOutput;
-    private int[] m_internalBundledOutput;
+    private final int[] m_internalBundledOutput;
     private boolean m_internalOutputChanged;
 
-    private int[] m_externalOutput;
+    private final int[] m_externalOutput;
-    private int[] m_externalBundledOutput;
+    private final int[] m_externalBundledOutput;
     private boolean m_externalOutputChanged;
 
-    private int[] m_input;
+    private final int[] m_input;
-    private int[] m_bundledInput;
+    private final int[] m_bundledInput;
     private boolean m_inputChanged;
         
-    private IPeripheral[] m_peripherals;
+    private final IPeripheral[] m_peripherals;
 
     public Computer( IComputerEnvironment environment, Terminal terminal, int id )
     {
@@ -370,10 +369,8 @@ public class Computer
                 // Advance our APIs
                 synchronized( m_apis )
                 {
-                    Iterator<ILuaAPI> it = m_apis.iterator();
+                    for(ILuaAPI api : m_apis)
-                    while( it.hasNext() )
                     {
-                        ILuaAPI api = it.next();
                         api.advance( _dt );
                     }
                 }
@@ -628,10 +625,8 @@ public class Computer
         ILuaMachine machine = new LuaJLuaMachine( this );
         
         // Add the APIs
-        Iterator<ILuaAPI> it = m_apis.iterator();
+        for(ILuaAPI api : m_apis)
-        while( it.hasNext() )
         {
-            ILuaAPI api = it.next();
             machine.addAPI( api );
             api.startup();
         }
@@ -794,10 +789,8 @@ public class Computer
                     // Shutdown our APIs
                     synchronized( m_apis )
                     {
-                        Iterator<ILuaAPI> it = m_apis.iterator();
+                        for(ILuaAPI api : m_apis)
-                        while( it.hasNext() )
                         {
-                            ILuaAPI api = it.next();
                             api.shutdown();
                         }
                     }

src/main/java/dan200/computercraft/core/computer/ComputerThread.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -13,14 +13,14 @@ import java.util.concurrent.LinkedBlockingQueue;
     
 public class ComputerThread
 {
-    private static Object m_lock;
+    private static final Object m_lock;
     
     private static Thread m_thread;
-    private static WeakHashMap <Object, LinkedBlockingQueue<ITask>> m_computerTasks;
+    private static final WeakHashMap <Object, LinkedBlockingQueue<ITask>> m_computerTasks;
-    private static ArrayList <LinkedBlockingQueue<ITask>> m_computerTasksActive;
+    private static final ArrayList <LinkedBlockingQueue<ITask>> m_computerTasksActive;
-    private static ArrayList <LinkedBlockingQueue<ITask>> m_computerTasksPending;
+    private static final ArrayList <LinkedBlockingQueue<ITask>> m_computerTasksPending;
-    private static Object m_defaultQueue;
+    private static final Object m_defaultQueue;
-    private static Object m_monitor;
+    private static final Object m_monitor;
 
     private static boolean m_running;
     private static boolean m_stopped;

src/main/java/dan200/computercraft/core/computer/IComputerEnvironment.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,13 +10,13 @@ import dan200.computercraft.api.filesystem.IWritableMount;
 
 public interface IComputerEnvironment
 {
-    public int getDay();
+    int getDay();
-    public double getTimeOfDay();
+    double getTimeOfDay();
-    public boolean isColour();
+    boolean isColour();
-    public long getComputerSpaceLimit();
+    long getComputerSpaceLimit();
-    public String getHostString();
+    String getHostString();
 
-    public int assignNewID();
+    int assignNewID();
-    public IWritableMount createSaveDirMount( String subPath, long capacity );
+    IWritableMount createSaveDirMount( String subPath, long capacity );
-    public IMount createResourceMount( String domain, String subPath );
+    IMount createResourceMount( String domain, String subPath );
 }

src/main/java/dan200/computercraft/core/computer/ITask.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,6 @@ package dan200.computercraft.core.computer;
 
 public interface ITask
 {
-    public Computer getOwner();
+    Computer getOwner();
-    public void execute();
+    void execute();
 }

src/main/java/dan200/computercraft/core/computer/MainThread.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/core/filesystem/ComboMount.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.api.filesystem.IMount;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
@@ -27,7 +28,7 @@ public class ComboMount implements IMount
     // IMount implementation
     
     @Override
-    public boolean exists( String path ) throws IOException
+    public boolean exists( @Nonnull String path ) throws IOException
     {
         for( int i=m_parts.length-1; i>=0; --i )
         {
@@ -41,7 +42,7 @@ public class ComboMount implements IMount
     }
     
     @Override
-    public boolean isDirectory( String path ) throws IOException
+    public boolean isDirectory( @Nonnull String path ) throws IOException
     {
         for( int i=m_parts.length-1; i>=0; --i )
         {
@@ -55,7 +56,7 @@ public class ComboMount implements IMount
     }
     
     @Override
-    public void list( String path, List<String> contents ) throws IOException
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
         // Combine the lists from all the mounts
         List<String> foundFiles = null;
@@ -83,9 +84,8 @@ public class ComboMount implements IMount
         {
             // We found multiple directories, so filter for duplicates
             Set<String> seen = new HashSet<String>();
-            for( int i=0; i<foundFiles.size(); ++i )
+            for(String file : foundFiles)
             {
-                String file = foundFiles.get(i);
                 if( seen.add( file ) )
                 {
                     contents.add( file );
@@ -99,7 +99,7 @@ public class ComboMount implements IMount
     }
     
     @Override
-    public long getSize( String path ) throws IOException
+    public long getSize( @Nonnull String path ) throws IOException
     {
         for( int i=m_parts.length-1; i>=0; --i )
         {
@@ -112,8 +112,9 @@ public class ComboMount implements IMount
         throw new IOException( "No such file" );
     }
 
+    @Nonnull
     @Override
-    public InputStream openForRead( String path ) throws IOException
+    public InputStream openForRead( @Nonnull String path ) throws IOException
     {
         for( int i=m_parts.length-1; i>=0; --i )
         {

src/main/java/dan200/computercraft/core/filesystem/EmptyMount.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.api.filesystem.IMount;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
@@ -21,30 +22,31 @@ public class EmptyMount implements IMount
     // IMount implementation
     
     @Override
-    public boolean exists( String path ) throws IOException
+    public boolean exists( @Nonnull String path ) throws IOException
     {
         return path.isEmpty();
     }
     
     @Override
-    public boolean isDirectory( String path ) throws IOException
+    public boolean isDirectory( @Nonnull String path ) throws IOException
     {
         return path.isEmpty();
     }
     
     @Override
-    public void list( String path, List<String> contents ) throws IOException
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
     }
     
     @Override
-    public long getSize( String path ) throws IOException
+    public long getSize( @Nonnull String path ) throws IOException
     {
         return 0;
     }
 
+    @Nonnull
     @Override
-    public InputStream openForRead( String path ) throws IOException
+    public InputStream openForRead( @Nonnull String path ) throws IOException
     {
         return null;
     }

src/main/java/dan200/computercraft/core/filesystem/FileMount.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.api.filesystem.IWritableMount;
 
+import javax.annotation.Nonnull;
 import java.io.*;
 import java.util.List;
 
@@ -39,14 +40,14 @@ public class FileMount implements IWritableMount
         }
         
         @Override
-        public void write( byte[] b ) throws IOException
+        public void write( @Nonnull byte[] b ) throws IOException
         {
             count( b.length );
             m_innerStream.write( b );
         }
         
         @Override
-        public void write( byte[] b, int off, int len ) throws IOException 
+        public void write( @Nonnull byte[] b, int off, int len ) throws IOException
         {
             count( len );
             m_innerStream.write( b, off, len );
@@ -94,7 +95,7 @@ public class FileMount implements IWritableMount
     // IMount implementation
     
     @Override
-    public boolean exists( String path ) throws IOException
+    public boolean exists( @Nonnull String path ) throws IOException
     {
         if( !created() )
         {
@@ -108,7 +109,7 @@ public class FileMount implements IWritableMount
     }
     
     @Override
-    public boolean isDirectory( String path ) throws IOException
+    public boolean isDirectory( @Nonnull String path ) throws IOException
     {
         if( !created() )
         {
@@ -122,7 +123,7 @@ public class FileMount implements IWritableMount
     }
     
     @Override
-    public void list( String path, List<String> contents ) throws IOException
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
         if( !created() )
         {
@@ -153,7 +154,7 @@ public class FileMount implements IWritableMount
     }
 
     @Override
-    public long getSize( String path ) throws IOException
+    public long getSize( @Nonnull String path ) throws IOException
     {
         if( !created() )
         {
@@ -180,8 +181,9 @@ public class FileMount implements IWritableMount
         throw new IOException( "No such file" );
     }
     
+    @Nonnull
     @Override
-    public InputStream openForRead( String path ) throws IOException
+    public InputStream openForRead( @Nonnull String path ) throws IOException
     {
         if( created() )
         {
@@ -197,7 +199,7 @@ public class FileMount implements IWritableMount
     // IWritableMount implementation
     
     @Override
-    public void makeDirectory( String path ) throws IOException
+    public void makeDirectory( @Nonnull String path ) throws IOException
     {
         create();
         File file = getRealPath( path );
@@ -236,7 +238,7 @@ public class FileMount implements IWritableMount
     }
     
     @Override
-    public void delete( String path ) throws IOException
+    public void delete( @Nonnull String path ) throws IOException
     {
         if( path.length() == 0 )
         {
@@ -259,9 +261,9 @@ public class FileMount implements IWritableMount
         if( file.isDirectory() )
         {
             String[] children = file.list();
-            for( int i=0; i<children.length; i++ )
+            for( String aChildren : children )
             {
-                deleteRecursively( new File( file, children[i] ) );
+                deleteRecursively( new File( file, aChildren ) );
             }
         }
         
@@ -278,8 +280,9 @@ public class FileMount implements IWritableMount
         }
     }
     
+    @Nonnull
     @Override
-    public OutputStream openForWrite( String path ) throws IOException
+    public OutputStream openForWrite( @Nonnull String path ) throws IOException
     {
         create();
         File file = getRealPath( path );
@@ -309,8 +312,9 @@ public class FileMount implements IWritableMount
         }
     }
     
+    @Nonnull
     @Override
-    public OutputStream openForAppend( String path ) throws IOException
+    public OutputStream openForAppend( @Nonnull String path ) throws IOException
     {
         if( created() )
         {
@@ -372,9 +376,9 @@ public class FileMount implements IWritableMount
         {
             long size = MINIMUM_FILE_SIZE;
             String[] contents = file.list();
-            for( int i=0; i<contents.length; ++i )
+            for( String content : contents )
             {
-                size += measureUsedSpace( new File( file, contents[i] ) );
+                size += measureUsedSpace( new File( file, content ) );
             }
             return size;
         }

src/main/java/dan200/computercraft/core/filesystem/FileSystem.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -327,7 +327,7 @@ public class FileSystem
             throw new NullPointerException();
         }
         location = sanitizePath( location );
-        if( location.indexOf( ".." ) != -1 ) {
+        if( location.contains( ".." ) ) {
             throw new FileSystemException( "Cannot mount below the root" );
         }                    
         mount( new MountWrapper( label, location, mount ) );
@@ -427,10 +427,10 @@ public class FileSystem
         mount.list( path, list );
         
         // Add any mounts that are mounted at this location
-        Iterator<MountWrapper> it = m_mounts.values().iterator();
+        for( MountWrapper otherMount : m_mounts.values() )
-        while( it.hasNext() ) {
+        {
-            MountWrapper otherMount = it.next();
+            if( getDirectory( otherMount.getLocation() ).equals( path ) )
-            if( getDirectory( otherMount.getLocation() ).equals( path ) ) {
+            {
                 list.add( getName( otherMount.getLocation() ) );
             }
         }
@@ -445,9 +445,8 @@ public class FileSystem
     private void findIn( String dir, List<String> matches, Pattern wildPattern ) throws FileSystemException
     {
         String[] list = list( dir );
-        for( int i=0; i<list.length; ++i )
+        for( String entry : list )
         {
-            String entry = list[i];
             String entryPath = dir.isEmpty() ? entry : (dir + "/" + entry);
             if( wildPattern.matcher( entryPath ).matches() )
             {
@@ -910,7 +909,7 @@ public class FileSystem
             char c = path.charAt(i);
             if( c >= 32 && Arrays.binarySearch( specialChars, c ) < 0 && (allowWildcards || c != '*') )
             {
-                cleanName.append((char)c);
+                cleanName.append( c );
             }
         }
         path = cleanName.toString();
@@ -918,30 +917,42 @@ public class FileSystem
         // Collapse the string into its component parts, removing ..'s
         String[] parts = path.split("/");
         Stack<String> outputParts = new Stack<String>();
-        for( int n=0; n<parts.length; ++n ) {
+        for( String part : parts )
-            String part = parts[n];
+        {
-            if( part.length() == 0 || part.equals(".") )
+            if( part.length() == 0 || part.equals( "." ) )
             {
                 // . is redundant
                 continue;
-            } else if( part.equals("..") || part.equals( "..." ) ) {
+            }
+            else if( part.equals( ".." ) || part.equals( "..." ) )
+            {
                 // .. or ... can cancel out the last folder entered
-                if( !outputParts.empty() ) {
+                if( !outputParts.empty() )
+                {
                     String top = outputParts.peek();
-                    if( !top.equals("..") ) {
+                    if( !top.equals( ".." ) )
+                    {
                         outputParts.pop();
-                    } else {
-                        outputParts.push("..");
                     }
-                } else {
+                    else
-                    outputParts.push("..");
+                    {
+                        outputParts.push( ".." );
+                    }
                 }
-            } else if (part.length() >= 255) {
+                else
+                {
+                    outputParts.push( ".." );
+                }
+            }
+            else if( part.length() >= 255 )
+            {
                 // If part length > 255 and it is the last part
-                outputParts.push( part.substring(0, 255) );
+                outputParts.push( part.substring( 0, 255 ) );
-            } else {
+            }
+            else
+            {
                 // Anything else we add to the stack
-                outputParts.push(part);
+                outputParts.push( part );
             }
         }
         

src/main/java/dan200/computercraft/core/filesystem/FileSystemException.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -7,6 +7,8 @@
 package dan200.computercraft.core.filesystem;
 
 public class FileSystemException extends Exception {
+    private static final long serialVersionUID = -2500631644868104029L;
+
     FileSystemException( String s ) {
         super( s );
     }

src/main/java/dan200/computercraft/core/filesystem/IMountedFile.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,5 +9,5 @@ package dan200.computercraft.core.filesystem;
 import java.io.IOException;
 
 public interface IMountedFile {
-    public void close() throws IOException;
+    void close() throws IOException;
 }

src/main/java/dan200/computercraft/core/filesystem/IMountedFileBinary.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,8 +9,8 @@ package dan200.computercraft.core.filesystem;
 import java.io.IOException;
 
 public interface IMountedFileBinary extends IMountedFile {
-    public int read() throws IOException;
+    int read() throws IOException;
-    public void write(int i) throws IOException;
+    void write( int i ) throws IOException;
-    public void close() throws IOException;
+    void close() throws IOException;
-    public void flush() throws IOException;
+    void flush() throws IOException;
 }

src/main/java/dan200/computercraft/core/filesystem/IMountedFileNormal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,8 +9,8 @@ package dan200.computercraft.core.filesystem;
 import java.io.IOException;
 
 public interface IMountedFileNormal extends IMountedFile {
-    public String readLine() throws IOException;
+    String readLine() throws IOException;
-    public void write(String s, int off, int len, boolean newLine) throws IOException;
+    void write( String s, int off, int len, boolean newLine ) throws IOException;
-    public void close() throws IOException;
+    void close() throws IOException;
-    public void flush() throws IOException;
+    void flush() throws IOException;
 }

src/main/java/dan200/computercraft/core/filesystem/JarMount.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.api.filesystem.IMount;
 
+import javax.annotation.Nonnull;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -53,10 +54,7 @@ public class JarMount implements IMount
         
         public void list( List<String> contents )
         {
-            for( String child : m_children.keySet() )
+            contents.addAll( m_children.keySet() );
-            {
-                contents.add( child );
-            }
         }
                 
         public void insertChild( FileInZip child )
@@ -178,14 +176,14 @@ public class JarMount implements IMount
     // IMount implementation
     
     @Override
-    public boolean exists( String path ) throws IOException
+    public boolean exists( @Nonnull String path ) throws IOException
     {
         FileInZip file = m_root.getFile( path );
         return file != null;
     }
     
     @Override
-    public boolean isDirectory( String path ) throws IOException
+    public boolean isDirectory( @Nonnull String path ) throws IOException
     {
         FileInZip file = m_root.getFile( path );
         if( file != null )
@@ -196,7 +194,7 @@ public class JarMount implements IMount
     }
     
     @Override
-    public void list( String path, List<String> contents ) throws IOException
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
         FileInZip file = m_root.getFile( path );
         if( file != null && file.isDirectory() )
@@ -210,7 +208,7 @@ public class JarMount implements IMount
     }
     
     @Override
-    public long getSize( String path ) throws IOException
+    public long getSize( @Nonnull String path ) throws IOException
     {
         FileInZip file = m_root.getFile( path );
         if( file != null )
@@ -220,8 +218,9 @@ public class JarMount implements IMount
         throw new IOException( "No such file" );
     }
 
+    @Nonnull
     @Override
-    public InputStream openForRead( String path ) throws IOException
+    public InputStream openForRead( @Nonnull String path ) throws IOException
     {
         FileInZip file = m_root.getFile( path );
         if( file != null && !file.isDirectory() )

src/main/java/dan200/computercraft/core/filesystem/SubMount.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import dan200.computercraft.api.filesystem.IMount;
 
+import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
@@ -26,31 +27,32 @@ public class SubMount implements IMount
     // IMount implementation
     
     @Override
-    public boolean exists( String path ) throws IOException
+    public boolean exists( @Nonnull String path ) throws IOException
     {
         return m_parent.exists( getFullPath( path ) );
     }
     
     @Override
-    public boolean isDirectory( String path ) throws IOException
+    public boolean isDirectory( @Nonnull String path ) throws IOException
     {
         return m_parent.isDirectory( getFullPath( path ) );
     }
     
     @Override
-    public void list( String path, List<String> contents ) throws IOException
+    public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
         m_parent.list( getFullPath( path ), contents );
     }
     
     @Override
-    public long getSize( String path ) throws IOException
+    public long getSize( @Nonnull String path ) throws IOException
     {
         return m_parent.getSize( getFullPath( path ) );
     }
 
+    @Nonnull
     @Override
-    public InputStream openForRead( String path ) throws IOException
+    public InputStream openForRead( @Nonnull String path ) throws IOException
     {
         return m_parent.openForRead( getFullPath( path ) );
     }

src/main/java/dan200/computercraft/core/lua/ILuaMachine.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,17 +12,17 @@ import java.io.OutputStream;
 
 public interface ILuaMachine
 {
-    public void addAPI( ILuaAPI api );
+    void addAPI( ILuaAPI api );
     
-    public void loadBios( InputStream bios );
+    void loadBios( InputStream bios );
-    public void handleEvent( String eventName, Object[] arguments );
+    void handleEvent( String eventName, Object[] arguments );
-    public void softAbort( String abortMessage );
+    void softAbort( String abortMessage );
-    public void hardAbort( String abortMessage );
+    void hardAbort( String abortMessage );
     
-    public boolean saveState( OutputStream output );
+    boolean saveState( OutputStream output );
-    public boolean restoreState( InputStream input );
+    boolean restoreState( InputStream input );
     
-    public boolean isFinished();
+    boolean isFinished();
     
-    public void unload();
+    void unload();
 }

src/main/java/dan200/computercraft/core/lua/LuaJLuaMachine.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -21,10 +21,10 @@ import org.luaj.vm2.lib.VarArgFunction;
 import org.luaj.vm2.lib.ZeroArgFunction;
 import org.luaj.vm2.lib.jse.JsePlatform;
 
+import javax.annotation.Nonnull;
 import java.io.*;
 import java.util.HashMap;
 import java.util.IdentityHashMap;
-import java.util.Iterator;
 import java.util.Map;
 
 public class LuaJLuaMachine implements ILuaMachine
@@ -128,9 +128,9 @@ public class LuaJLuaMachine implements ILuaMachine
         // Add the methods of an API to the global table
         LuaTable table = wrapLuaObject( api );
         String[] names = api.getNames();
-        for( int i=0; i<names.length; ++i )
+        for( String name : names )
         {
-            m_globals.set( names[i], table );
+            m_globals.set( name, table );
         }
     }
     
@@ -146,7 +146,7 @@ public class LuaJLuaMachine implements ILuaMachine
         try
         {
             // Read the whole bios into a string
-            String biosText = null;
+            String biosText;
             try
             {
                 InputStreamReader isr;
@@ -316,8 +316,6 @@ public class LuaJLuaMachine implements ILuaMachine
             throw new LuaError( abortMessage );
         }
     }
-
-    private static long s_nextUnusedTaskID = 0;
     
     private LuaTable wrapLuaObject( ILuaObject object )
     {
@@ -335,10 +333,11 @@ public class LuaJLuaMachine implements ILuaMachine
                     {
                         tryAbort();
                         Object[] arguments = toObjects( _args, 1 );
-                        Object[] results = null;
+                        Object[] results;
                         try
                         {
                             results = apiObject.callMethod( new ILuaContext() {
+                                @Nonnull
                                 @Override
                                 public Object[] pullEvent( String filter ) throws LuaException, InterruptedException
                                 {
@@ -350,12 +349,14 @@ public class LuaJLuaMachine implements ILuaMachine
                                     return results;
                                 }
                                 
+                                @Nonnull
                                 @Override
                                 public Object[] pullEventRaw( String filter ) throws InterruptedException
                                 {
                                     return yield( new Object[] { filter } );
                                 }
                                 
+                                @Nonnull
                                 @Override
                                 public Object[] yield( Object[] yieldArgs ) throws InterruptedException
                                 {
@@ -372,7 +373,7 @@ public class LuaJLuaMachine implements ILuaMachine
                                 }
 
                                 @Override
-                                public long issueMainThreadTask( final ILuaTask task ) throws LuaException
+                                public long issueMainThreadTask( @Nonnull final ILuaTask task ) throws LuaException
                                 {
                                     // Issue command
                                     final long taskID = MainThread.getUniqueTaskID();
@@ -395,10 +396,7 @@ public class LuaJLuaMachine implements ILuaMachine
                                                     Object[] eventArguments = new Object[ results.length + 2 ];
                                                     eventArguments[ 0 ] = taskID;
                                                     eventArguments[ 1 ] = true;
-                                                    for( int i = 0; i < results.length; ++i )
+                                                    System.arraycopy( results, 0, eventArguments, 2, results.length );
-                                                    {
-                                                        eventArguments[ i + 2 ] = results[ i ];
-                                                    }
                                                     m_computer.queueEvent( "task_complete", eventArguments );
                                                 }
                                                 else
@@ -431,7 +429,7 @@ public class LuaJLuaMachine implements ILuaMachine
                                 }
 
                                 @Override
-                                public Object[] executeMainThreadTask( final ILuaTask task ) throws LuaException, InterruptedException
+                                public Object[] executeMainThreadTask( @Nonnull final ILuaTask task ) throws LuaException, InterruptedException
                                 {
                                     // Issue task
                                     final long taskID = issueMainThreadTask( task );
@@ -448,10 +446,7 @@ public class LuaJLuaMachine implements ILuaMachine
                                                 if( (Boolean)response[ 2 ] )
                                                 {
                                                     // Extract the return values from the event and return them
-                                                    for( int i = 0; i < returnValues.length; ++i )
+                                                    System.arraycopy( response, 3, returnValues, 0, returnValues.length );
-                                                    {
-                                                        returnValues[ i ] = response[ i + 3 ];
-                                                    }
                                                     return returnValues;
                                                 }
                                                 else
@@ -506,7 +501,7 @@ public class LuaJLuaMachine implements ILuaMachine
         }
         else if( object instanceof Boolean )
         {
-            boolean b = ((Boolean)object).booleanValue();
+            boolean b = (Boolean) object;
             return LuaValue.valueOf( b );
         }
         else if( object instanceof String )
@@ -534,10 +529,8 @@ public class LuaJLuaMachine implements ILuaMachine
                 m_valuesInProgress.put( object, table );
 
                 // Convert all keys
-                Iterator it = ((Map)object).entrySet().iterator();
+                for( Map.Entry<?, ?> pair : ((Map<?, ?>) object).entrySet() )
-                while( it.hasNext() )
                 {
-                    Map.Entry pair = (Map.Entry)it.next();
                     LuaValue key = toValue( pair.getKey() );
                     LuaValue value = toValue( pair.getValue() );
                     if( !key.isnil() && !value.isnil() )
@@ -558,8 +551,7 @@ public class LuaJLuaMachine implements ILuaMachine
         }
         else if( object instanceof ILuaObject )
         {
-            LuaValue table = wrapLuaObject( (ILuaObject)object );
+            return wrapLuaObject( (ILuaObject)object );
-            return table;
         }
         else
         {
@@ -627,7 +619,7 @@ public class LuaJLuaMachine implements ILuaMachine
                     {
                         return m_objectsInProgress.get( value );
                     }
-                    Map table = new HashMap();
+                    Map<Object, Object> table = new HashMap<Object, Object>();
                     m_objectsInProgress.put( value, table );
 
                     // Convert all keys

src/main/java/dan200/computercraft/core/terminal/Terminal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/core/terminal/TextBuffer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/server/proxy/CCTurtleProxyServer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/server/proxy/ComputerCraftProxyServer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -6,7 +6,6 @@
 
 package dan200.computercraft.server.proxy;
 
-import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.shared.computer.blocks.TileComputer;
 import dan200.computercraft.shared.peripheral.diskdrive.TileDiskDrive;
 import dan200.computercraft.shared.peripheral.printer.TilePrinter;

src/main/java/dan200/computercraft/shared/common/BlockDirectional.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/common/BlockGeneric.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,7 +10,6 @@ import net.minecraft.block.Block;
 import net.minecraft.block.ITileEntityProvider;
 import net.minecraft.block.material.Material;
 import net.minecraft.block.state.IBlockState;
-import net.minecraft.enchantment.EnchantmentHelper;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.EntityLivingBase;
 import net.minecraft.entity.player.EntityPlayer;
@@ -25,8 +24,8 @@ import net.minecraft.world.Explosion;
 import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.List;
 
 public abstract class BlockGeneric extends Block implements
@@ -43,12 +42,13 @@ public abstract class BlockGeneric extends Block implements
     protected abstract TileGeneric createTile( int damage );
 
     @Override
-    public final void dropBlockAsItemWithChance( World world, BlockPos pos, IBlockState state, float chance, int fortune )
+    public final void dropBlockAsItemWithChance( World world, @Nonnull BlockPos pos, @Nonnull IBlockState state, float chance, int fortune )
     {
     }
 
+    @Nonnull
     @Override
-    public final List<ItemStack> getDrops( IBlockAccess world, BlockPos pos, IBlockState state, int fortune )
+    public final List<ItemStack> getDrops( IBlockAccess world, BlockPos pos, @Nonnull IBlockState state, int fortune )
     {
         ArrayList<ItemStack> drops = new ArrayList<ItemStack>( 1 );
         TileEntity tile = world.getTileEntity( pos );
@@ -60,6 +60,7 @@ public abstract class BlockGeneric extends Block implements
         return drops;
     }
 
+    @Nonnull
     @Override
     public final IBlockState onBlockPlaced( World world, BlockPos pos, EnumFacing side, float hitX, float hitY, float hitZ, int damage, EntityLivingBase placer )
     {
@@ -67,7 +68,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    public final boolean removedByPlayer( IBlockState state, World world, BlockPos pos, EntityPlayer player, boolean willHarvest )
+    public final boolean removedByPlayer( @Nonnull IBlockState state, World world, @Nonnull BlockPos pos, @Nonnull EntityPlayer player, boolean willHarvest )
     {
         if( !world.isRemote )
         {
@@ -94,10 +95,8 @@ public abstract class BlockGeneric extends Block implements
         // Drop items
         if( drops.size() > 0 )
         {
-            Iterator<ItemStack> it = drops.iterator();
+            for (ItemStack item : drops)
-            while( it.hasNext() )
             {
-                ItemStack item = it.next();
                 dropItem( world, pos, item );
             }
         }
@@ -109,7 +108,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    public final void breakBlock( World world, BlockPos pos, IBlockState newState )
+    public final void breakBlock( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull IBlockState newState )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric )
@@ -121,8 +120,9 @@ public abstract class BlockGeneric extends Block implements
         world.removeTileEntity( pos );
     }
 
+    @Nonnull
     @Override
-    public final ItemStack getPickBlock( IBlockState state, RayTraceResult target, World world, BlockPos pos, EntityPlayer player )
+    public final ItemStack getPickBlock( @Nonnull IBlockState state, RayTraceResult target, @Nonnull World world, @Nonnull BlockPos pos, EntityPlayer player )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric )
@@ -134,7 +134,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    protected final ItemStack createStackedBlock( IBlockState state )
+    protected final ItemStack createStackedBlock( @Nonnull IBlockState state )
     {
         return null;
     }
@@ -152,6 +152,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
+    @Deprecated
     public final void neighborChanged( IBlockState state, World world, BlockPos pos, Block block )
     {
         TileEntity tile = world.getTileEntity( pos );
@@ -174,7 +175,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    public final boolean isSideSolid( IBlockState state, IBlockAccess world, BlockPos pos, EnumFacing side )
+    public final boolean isSideSolid( IBlockState state, @Nonnull IBlockAccess world, @Nonnull BlockPos pos, EnumFacing side )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric )
@@ -192,7 +193,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    public float getExplosionResistance( World world, BlockPos pos, Entity exploder, Explosion explosion )
+    public float getExplosionResistance( World world, BlockPos pos, @Nonnull Entity exploder, Explosion explosion )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric && tile.hasWorldObj() )
@@ -206,7 +207,9 @@ public abstract class BlockGeneric extends Block implements
         return super.getExplosionResistance( exploder );
     }
 
+    @Nonnull
     @Override
+    @Deprecated
     public final AxisAlignedBB getBoundingBox( IBlockState state, IBlockAccess world, BlockPos pos )
     {
         TileEntity tile = world.getTileEntity( pos );
@@ -218,14 +221,17 @@ public abstract class BlockGeneric extends Block implements
         return FULL_BLOCK_AABB;
     }
 
+    @Nonnull
     @Override
-    public AxisAlignedBB getSelectedBoundingBox( IBlockState state, World worldIn, BlockPos pos )
+    @Deprecated
+    public final AxisAlignedBB getSelectedBoundingBox( IBlockState state, @Nonnull World world, @Nonnull BlockPos pos )
     {
-        return getBoundingBox( state, worldIn, pos ).offset( pos );
+        return getBoundingBox( state, world, pos ).offset( pos );
     }
 
     @Override
-    public final AxisAlignedBB getCollisionBoundingBox( IBlockState state, World world, BlockPos pos )
+    @Deprecated
+    public final AxisAlignedBB getCollisionBoundingBox( IBlockState state, @Nonnull World world, @Nonnull BlockPos pos )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric && tile.hasWorldObj() )
@@ -252,7 +258,8 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
-    public final void addCollisionBoxToList( IBlockState state, World world, BlockPos pos, AxisAlignedBB bigBox, List<AxisAlignedBB> list, Entity entity )
+    @Deprecated
+    public final void addCollisionBoxToList( IBlockState state, @Nonnull World world, @Nonnull BlockPos pos, @Nonnull AxisAlignedBB bigBox, @Nonnull List<AxisAlignedBB> list, Entity entity )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof TileGeneric && tile.hasWorldObj() )
@@ -266,10 +273,8 @@ public abstract class BlockGeneric extends Block implements
             // Add collision bounds to list
             if( collision.size() > 0 )
             {
-                Iterator<AxisAlignedBB> it = collision.iterator();
+                for (AxisAlignedBB localBounds : collision)
-                while( it.hasNext() )
                 {
-                    AxisAlignedBB localBounds = it.next();
                     addCollisionBoxToList( pos, bigBox, list, localBounds );
                 }
             }
@@ -277,6 +282,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
+    @Deprecated
     public final boolean canProvidePower( IBlockState state )
     {
         return true;
@@ -295,6 +301,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
+    @Deprecated
     public final int getStrongPower( IBlockState state, IBlockAccess world, BlockPos pos, EnumFacing oppositeSide )
     {
         TileEntity tile = world.getTileEntity( pos );
@@ -307,6 +314,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
+    @Deprecated
     public final int getWeakPower( IBlockState state, IBlockAccess world, BlockPos pos, EnumFacing oppositeSide )
     {
         return getStrongPower( state, world, pos, oppositeSide );
@@ -335,6 +343,7 @@ public abstract class BlockGeneric extends Block implements
     }
 
     @Override
+    @Deprecated
     public boolean eventReceived( IBlockState state, World world, BlockPos pos, int eventID, int eventParameter )
     {
         if( world.isRemote )
@@ -349,14 +358,16 @@ public abstract class BlockGeneric extends Block implements
         return true;
     }
 
+    @Nonnull
     @Override
-    public final TileEntity createTileEntity( World world, IBlockState state )
+    public final TileEntity createTileEntity( @Nonnull World world, @Nonnull IBlockState state )
     {
         return createTile( state );
     }
 
+    @Nonnull
     @Override
-    public final TileEntity createNewTileEntity( World world, int damage )
+    public final TileEntity createNewTileEntity( @Nonnull World world, int damage )
     {
         return createTile( damage );
     }

src/main/java/dan200/computercraft/shared/common/ClientTerminal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/common/DefaultBundledRedstoneProvider.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,6 +12,8 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+
 public class DefaultBundledRedstoneProvider implements IBundledRedstoneProvider
 {
     public DefaultBundledRedstoneProvider()
@@ -19,7 +21,7 @@ public class DefaultBundledRedstoneProvider implements IBundledRedstoneProvider
     }
 
     @Override
-    public int getBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side )
+    public int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
     {
         return getDefaultBundledRedstoneOutput( world, pos, side );
     }

src/main/java/dan200/computercraft/shared/common/IDirectionalTile.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,6 +10,6 @@ import net.minecraft.util.EnumFacing;
 
 public interface IDirectionalTile
 {
-    public EnumFacing getDirection();
+    EnumFacing getDirection();
-    public void setDirection( EnumFacing dir );
+    void setDirection( EnumFacing dir );
 }

src/main/java/dan200/computercraft/shared/common/ITerminal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,6 +10,6 @@ import dan200.computercraft.core.terminal.Terminal;
 
 public interface ITerminal
 {
-    public Terminal getTerminal();
+    Terminal getTerminal();
-    public boolean isColour();
+    boolean isColour();
 }

src/main/java/dan200/computercraft/shared/common/ITerminalTile.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,5 +8,5 @@ package dan200.computercraft.shared.common;
 
 public interface ITerminalTile
 {
-    public ITerminal getTerminal();
+    ITerminal getTerminal();
 }

src/main/java/dan200/computercraft/shared/common/ServerTerminal.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/common/TileGeneric.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -15,7 +15,6 @@ import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.network.NetworkManager;
-import net.minecraft.network.Packet;
 import net.minecraft.network.play.server.SPacketUpdateTileEntity;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.math.AxisAlignedBB;
@@ -23,6 +22,8 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.util.List;
 
 public abstract class TileGeneric extends TileEntity
@@ -48,6 +49,7 @@ public abstract class TileGeneric extends TileEntity
     {
     }
 
+    @Nullable
     public BlockGeneric getBlock()
     {
         Block block = worldObj.getBlockState( getPos() ).getBlock();
@@ -77,7 +79,7 @@ public abstract class TileGeneric extends TileEntity
         worldObj.setBlockState( getPos(), newState, 3 );
     }
 
-    public void getDroppedItems( List<ItemStack> drops, boolean creative )
+    public void getDroppedItems( @Nonnull List<ItemStack> drops, boolean creative )
     {
     }
 
@@ -95,7 +97,7 @@ public abstract class TileGeneric extends TileEntity
     {
     }
 
-    public void onNeighbourTileEntityChange( BlockPos neighbour )
+    public void onNeighbourTileEntityChange( @Nonnull BlockPos neighbour )
     {
     }
 
@@ -109,12 +111,13 @@ public abstract class TileGeneric extends TileEntity
         return false;
     }
 
+    @Nonnull
     public AxisAlignedBB getBounds()
     {
         return new AxisAlignedBB( 0.0, 0.0, 0.0, 1.0, 1.0, 1.0 );
     }
 
-    public void getCollisionBounds( List<AxisAlignedBB> bounds )
+    public void getCollisionBounds( @Nonnull List<AxisAlignedBB> bounds )
     {
         bounds.add( getBounds() );
     }
@@ -129,12 +132,12 @@ public abstract class TileGeneric extends TileEntity
         return 0;
     }
 
-    public boolean getBundledRedstoneConnectivity( EnumFacing side )
+    public boolean getBundledRedstoneConnectivity( @Nonnull EnumFacing side )
     {
         return false;
     }
 
-    public int getBundledRedstoneOutput( EnumFacing side )
+    public int getBundledRedstoneOutput( @Nonnull EnumFacing side )
     {
         return 0;
     }
@@ -163,11 +166,11 @@ public abstract class TileGeneric extends TileEntity
         return false;
     }
 
-    protected void writeDescription( NBTTagCompound nbttagcompound )
+    protected void writeDescription( @Nonnull NBTTagCompound nbttagcompound )
     {
     }
 
-    protected void readDescription( NBTTagCompound nbttagcompound )
+    protected void readDescription( @Nonnull NBTTagCompound nbttagcompound )
     {
     }
 
@@ -186,7 +189,7 @@ public abstract class TileGeneric extends TileEntity
     }
 
     @Override
-    public boolean shouldRefresh( World world, BlockPos pos, IBlockState oldState, IBlockState newState )
+    public boolean shouldRefresh( World world, BlockPos pos, @Nonnull IBlockState oldState, @Nonnull IBlockState newState )
     {
         return newState.getBlock() != oldState.getBlock();
     }
@@ -215,6 +218,7 @@ public abstract class TileGeneric extends TileEntity
         }
     }
 
+    @Nonnull
     @Override
     public NBTTagCompound getUpdateTag ()
     {
@@ -224,7 +228,7 @@ public abstract class TileGeneric extends TileEntity
     }
 
     @Override
-    public void handleUpdateTag (NBTTagCompound tag)
+    public void handleUpdateTag ( @Nonnull NBTTagCompound tag)
     {
         super.handleUpdateTag(tag);
         readDescription( tag );

src/main/java/dan200/computercraft/shared/computer/apis/CommandAPI.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -21,9 +21,9 @@ import net.minecraft.command.ICommandManager;
 import net.minecraft.command.ICommandSender;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.util.math.BlockPos;
-import net.minecraft.util.ResourceLocation;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -61,6 +61,7 @@ public class CommandAPI implements ILuaAPI
     {
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -111,7 +112,7 @@ public class CommandAPI implements ILuaAPI
         // Get the details of the block
         IBlockState state = world.getBlockState( pos );
         Block block = state.getBlock();
-        String name = ((ResourceLocation)Block.REGISTRY.getNameForObject( block )).toString();
+        String name = Block.REGISTRY.getNameForObject( block ).toString();
         int metadata = block.getMetaFromState( state );
 
         Map<Object, Object> table = new HashMap<Object, Object>();
@@ -119,9 +120,8 @@ public class CommandAPI implements ILuaAPI
         table.put( "metadata", metadata );
 
         Map<Object, Object> stateTable = new HashMap<Object, Object>();
-        for( Object o : state.getActualState( world, pos ).getProperties().entrySet() )
+        for( ImmutableMap.Entry<IProperty<?>, Comparable<?>> entry : state.getActualState( world, pos ).getProperties().entrySet() )
         {
-            ImmutableMap.Entry<IProperty, Object> entry = (ImmutableMap.Entry<IProperty, Object>)o;
             String propertyName = entry.getKey().getName();
             Object value = entry.getValue();
             if( value instanceof String || value instanceof Number || value instanceof Boolean )
@@ -139,7 +139,7 @@ public class CommandAPI implements ILuaAPI
     }
 
     @Override
-    public Object[] callMethod( ILuaContext context, int method, Object[] arguments ) throws LuaException, InterruptedException
+    public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException
     {
         switch( method )
         {
@@ -193,12 +193,11 @@ public class CommandAPI implements ILuaAPI
                         {
                             ICommandManager commandManager = server.getCommandManager();
                             ICommandSender commmandSender = m_computer.getCommandSender();
-                            Map commands = commandManager.getCommands();
+                            Map<String, ICommand> commands = commandManager.getCommands();
-                            for( Object entryObject : commands.entrySet() )
+                            for( Map.Entry<String, ICommand> entry : commands.entrySet() )
                             {
-                                Map.Entry entry = (Map.Entry)entryObject;
+                                String name = entry.getKey();
-                                String name = (String)entry.getKey();
+                                ICommand command = entry.getValue();
-                                ICommand command = (ICommand)entry.getValue();
                                 try
                                 {
                                     if( command.checkPermission( server, commmandSender ) )

src/main/java/dan200/computercraft/shared/computer/blocks/BlockCommandComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -9,10 +9,8 @@ package dan200.computercraft.shared.computer.blocks;
 import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.IComputer;
-import dan200.computercraft.shared.peripheral.common.TilePeripheralBase;
 import dan200.computercraft.shared.util.DirectionUtil;
 import net.minecraft.block.material.Material;
-import net.minecraft.block.properties.IProperty;
 import net.minecraft.block.properties.PropertyDirection;
 import net.minecraft.block.properties.PropertyEnum;
 import net.minecraft.block.state.BlockStateContainer;
@@ -25,6 +23,8 @@ import net.minecraft.util.EnumFacing;
 import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+
 public class BlockCommandComputer extends BlockComputerBase
 {
     // Statics
@@ -32,7 +32,7 @@ public class BlockCommandComputer extends BlockComputerBase
     public static class Properties
     {
         public static final PropertyDirection FACING = PropertyDirection.create("facing", EnumFacing.Plane.HORIZONTAL);
-        public static final PropertyEnum<ComputerState> STATE = PropertyEnum.<ComputerState>create("state", ComputerState.class);
+        public static final PropertyEnum<ComputerState> STATE = PropertyEnum.create("state", ComputerState.class);
     }
 
     // Members
@@ -50,16 +50,16 @@ public class BlockCommandComputer extends BlockComputerBase
         );
     }
 
+    @Nonnull
     @Override
     protected BlockStateContainer createBlockState()
     {
-        return new BlockStateContainer(this, new IProperty[] {
+        return new BlockStateContainer(this, Properties.FACING, Properties.STATE );
-            Properties.FACING,
-            Properties.STATE
-        });
     }
 
+    @Nonnull
     @Override
+    @Deprecated
     public IBlockState getStateFromMeta( int meta )
     {
         EnumFacing dir = EnumFacing.getFront( meta & 0x7 );
@@ -73,11 +73,13 @@ public class BlockCommandComputer extends BlockComputerBase
     @Override
     public int getMetaFromState( IBlockState state )
     {
-        return ((EnumFacing)state.getValue( Properties.FACING )).getIndex();
+        return state.getValue( Properties.FACING ).getIndex();
     }
 
+    @Nonnull
     @Override
-    public IBlockState getActualState( IBlockState state, IBlockAccess world, BlockPos pos )
+    @Deprecated
+    public IBlockState getActualState( @Nonnull IBlockState state, IBlockAccess world, BlockPos pos )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof IComputerTile )

src/main/java/dan200/computercraft/shared/computer/blocks/BlockComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,7 +12,6 @@ import dan200.computercraft.shared.computer.core.IComputer;
 import dan200.computercraft.shared.computer.items.ItemComputer;
 import dan200.computercraft.shared.util.DirectionUtil;
 import net.minecraft.block.material.Material;
-import net.minecraft.block.properties.IProperty;
 import net.minecraft.block.properties.PropertyBool;
 import net.minecraft.block.properties.PropertyDirection;
 import net.minecraft.block.properties.PropertyEnum;
@@ -22,11 +21,13 @@ import net.minecraft.entity.EntityLivingBase;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
 import net.minecraft.tileentity.TileEntity;
-import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.EnumFacing;
+import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 
+import javax.annotation.Nonnull;
+
 public class BlockComputer extends BlockComputerBase
 {
     // Statics
@@ -34,7 +35,7 @@ public class BlockComputer extends BlockComputerBase
     {
         public static final PropertyDirection FACING = PropertyDirection.create("facing", EnumFacing.Plane.HORIZONTAL);
         public static final PropertyBool ADVANCED = PropertyBool.create("advanced");
-        public static final PropertyEnum<ComputerState> STATE = PropertyEnum.<ComputerState>create("state", ComputerState.class);
+        public static final PropertyEnum<ComputerState> STATE = PropertyEnum.create("state", ComputerState.class);
     }
 
     // Members
@@ -52,17 +53,16 @@ public class BlockComputer extends BlockComputerBase
         );
     }
 
+    @Nonnull
     @Override
     protected BlockStateContainer createBlockState()
     {
-        return new BlockStateContainer(this, new IProperty[] {
+        return new BlockStateContainer( this, Properties.FACING, Properties.ADVANCED, Properties.STATE );
-            Properties.FACING,
-            Properties.ADVANCED,
-            Properties.STATE
-        });
     }
 
+    @Nonnull
     @Override
+    @Deprecated
     public IBlockState getStateFromMeta( int meta )
     {
         EnumFacing dir = EnumFacing.getFront( meta & 0x7 );
@@ -86,8 +86,8 @@ public class BlockComputer extends BlockComputerBase
     @Override
     public int getMetaFromState( IBlockState state )
     {
-        int meta = ((EnumFacing)state.getValue( Properties.FACING )).getIndex();
+        int meta = state.getValue( Properties.FACING ).getIndex();
-        if( (Boolean)state.getValue( Properties.ADVANCED ) )
+        if( state.getValue( Properties.ADVANCED ) )
         {
             meta += 8;
         }
@@ -117,8 +117,10 @@ public class BlockComputer extends BlockComputerBase
         }
     }
 
+    @Nonnull
     @Override
-    public IBlockState getActualState( IBlockState state, IBlockAccess world, BlockPos pos )
+    @Deprecated
+    public IBlockState getActualState( @Nonnull IBlockState state, IBlockAccess world, BlockPos pos )
     {
         TileEntity tile = world.getTileEntity( pos );
         if( tile != null && tile instanceof IComputerTile )
@@ -148,7 +150,7 @@ public class BlockComputer extends BlockComputerBase
     @Override
     public ComputerFamily getFamily( IBlockState state )
     {
-        if( (Boolean)state.getValue( Properties.ADVANCED ) ) {
+        if( state.getValue( Properties.ADVANCED ) ) {
             return ComputerFamily.Advanced;
         } else {
             return ComputerFamily.Normal;

src/main/java/dan200/computercraft/shared/computer/blocks/BlockComputerBase.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/blocks/ComputerPeripheral.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,6 +12,8 @@ import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.shared.computer.core.ServerComputer;
 
+import javax.annotation.Nonnull;
+
 public class ComputerPeripheral
     implements IPeripheral
 {
@@ -26,12 +28,14 @@ public class ComputerPeripheral
         
     // IPeripheral implementation
 
+    @Nonnull
     @Override
     public String getType()
     {
         return m_type;
     }
 
+    @Nonnull
     @Override
     public String[] getMethodNames()
     {
@@ -45,7 +49,7 @@ public class ComputerPeripheral
     }
 
     @Override
-    public Object[] callMethod( IComputerAccess computer, ILuaContext context, int method, Object[] arguments ) throws LuaException
+    public Object[] callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException
     {
         switch( method )
         {
@@ -87,12 +91,12 @@ public class ComputerPeripheral
     }
 
     @Override
-    public void attach( IComputerAccess computer )
+    public void attach( @Nonnull IComputerAccess computer )
     {
     }
 
     @Override
-    public void detach( IComputerAccess computer )
+    public void detach( @Nonnull IComputerAccess computer )
     {
     }
 

src/main/java/dan200/computercraft/shared/computer/blocks/ComputerState.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,6 +8,8 @@ package dan200.computercraft.shared.computer.blocks;
 
 import net.minecraft.util.IStringSerializable;
 
+import javax.annotation.Nonnull;
+
 public enum ComputerState implements IStringSerializable
 {
     Off( "off" ),
@@ -16,11 +18,12 @@ public enum ComputerState implements IStringSerializable
 
     private String m_name;
 
-    private ComputerState( String name )
+    ComputerState( String name )
     {
         m_name = name;
     }
 
+    @Nonnull
     @Override
     public String getName()
     {

src/main/java/dan200/computercraft/shared/computer/blocks/IComputerTile.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,9 +12,9 @@ import dan200.computercraft.shared.computer.core.IComputer;
 
 public interface IComputerTile extends ITerminalTile
 {
-    public void setComputerID( int id );
+    void setComputerID( int id );
-    public void setLabel( String label );
+    void setLabel( String label );
-    public IComputer getComputer();
+    IComputer getComputer();
-    public IComputer createComputer();
+    IComputer createComputer();
-    public ComputerFamily getFamily();
+    ComputerFamily getFamily();
 }

src/main/java/dan200/computercraft/shared/computer/blocks/TileCommandComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -21,7 +21,7 @@ import net.minecraft.util.text.*;
 import net.minecraft.util.*;
 import net.minecraft.world.World;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -53,6 +53,7 @@ public class TileCommandComputer extends TileComputer
 
         // ICommandSender
 
+        @Nonnull
         @Override
         public ITextComponent getDisplayName()
         {
@@ -69,7 +70,7 @@ public class TileCommandComputer extends TileComputer
         }
 
         @Override
-        public void addChatMessage( ITextComponent chatComponent )
+        public void addChatMessage( @Nonnull ITextComponent chatComponent )
         {
             m_outputTable.put( m_outputTable.size() + 1, chatComponent.getUnformattedText() );
         }
@@ -80,12 +81,14 @@ public class TileCommandComputer extends TileComputer
             return level <= 2;
         }
 
+        @Nonnull
         @Override
         public BlockPos getPosition()
         {
             return TileCommandComputer.this.getPos();
         }
 
+        @Nonnull
         @Override
         public Vec3d getPositionVector()
         {
@@ -93,6 +96,7 @@ public class TileCommandComputer extends TileComputer
             return new Vec3d( pos.getX() + 0.5, pos.getY() + 0.5, pos.getZ() + 0.5 );
         }
 
+        @Nonnull
         @Override
         public World getEntityWorld()
         {
@@ -126,7 +130,7 @@ public class TileCommandComputer extends TileComputer
         }
 
         @Override
-        public void fillInInfo( ByteBuf buf )
+        public void fillInInfo( @Nonnull ByteBuf buf )
         {
         }
     }
@@ -142,7 +146,7 @@ public class TileCommandComputer extends TileComputer
     public EnumFacing getDirection()
     {
         IBlockState state = getBlockState();
-        return (EnumFacing)state.getValue( BlockCommandComputer.Properties.FACING );
+        return state.getValue( BlockCommandComputer.Properties.FACING );
     }
 
     @Override

src/main/java/dan200/computercraft/shared/computer/blocks/TileComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -17,6 +17,7 @@ import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.util.EnumFacing;
 
+import javax.annotation.Nonnull;
 import java.util.List;
 
 public class TileComputer extends TileComputerBase
@@ -47,7 +48,7 @@ public class TileComputer extends TileComputerBase
     }
 
     @Override
-    public void getDroppedItems( List<ItemStack> drops, boolean creative )
+    public void getDroppedItems( @Nonnull List<ItemStack> drops, boolean creative )
     {
         IComputer computer = getComputer();
         if( !creative || (computer != null && computer.getLabel() != null) )
@@ -69,7 +70,7 @@ public class TileComputer extends TileComputerBase
     }
 
     @Override
-    public final void readDescription( NBTTagCompound nbttagcompound )
+    public final void readDescription( @Nonnull NBTTagCompound nbttagcompound )
     {
         super.readDescription( nbttagcompound );
         updateBlock();
@@ -86,7 +87,7 @@ public class TileComputer extends TileComputerBase
     public EnumFacing getDirection()
     {
         IBlockState state = getBlockState();
-        return (EnumFacing)state.getValue( BlockComputer.Properties.FACING );
+        return state.getValue( BlockComputer.Properties.FACING );
     }
 
     @Override

src/main/java/dan200/computercraft/shared/computer/blocks/TileComputerBase.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -27,6 +27,8 @@ import net.minecraft.util.EnumHand;
 import net.minecraft.util.ITickable;
 import net.minecraft.util.math.BlockPos;
 
+import javax.annotation.Nonnull;
+
 public abstract class TileComputerBase extends TileGeneric
     implements IComputerTile, IDirectionalTile, ITickable
 {
@@ -167,14 +169,14 @@ public abstract class TileComputerBase extends TileGeneric
     }
 
     @Override
-    public boolean getBundledRedstoneConnectivity( EnumFacing side )
+    public boolean getBundledRedstoneConnectivity( @Nonnull EnumFacing side )
     {
         int localDir = remapLocalSide( DirectionUtil.toLocal( this, side ) );
         return !isRedstoneBlockedOnSide( localDir );
     }
 
     @Override
-    public int getBundledRedstoneOutput( EnumFacing side )
+    public int getBundledRedstoneOutput( @Nonnull EnumFacing side )
     {
         int localDir = remapLocalSide( DirectionUtil.toLocal( this, side ) );
         if( !isRedstoneBlockedOnSide( localDir ) )
@@ -198,7 +200,7 @@ public abstract class TileComputerBase extends TileGeneric
     }
 
     @Override
-    public void onNeighbourTileEntityChange( BlockPos neighbour )
+    public void onNeighbourTileEntityChange( @Nonnull BlockPos neighbour )
     {
         updateInput( neighbour );
     }
@@ -239,6 +241,7 @@ public abstract class TileComputerBase extends TileGeneric
         }
     }
 
+    @Nonnull
     @Override
     public NBTTagCompound writeToNBT( NBTTagCompound nbttagcompound )
     {
@@ -517,14 +520,14 @@ public abstract class TileComputerBase extends TileGeneric
     // Networking stuff
 
     @Override
-    public void writeDescription( NBTTagCompound nbttagcompound )
+    public void writeDescription( @Nonnull NBTTagCompound nbttagcompound )
     {
         super.writeDescription( nbttagcompound );
         nbttagcompound.setInteger( "instanceID", createServerComputer().getInstanceID() );
     }
 
     @Override
-    public void readDescription( NBTTagCompound nbttagcompound )
+    public void readDescription( @Nonnull NBTTagCompound nbttagcompound )
     {
         super.readDescription( nbttagcompound );
         m_instanceID = nbttagcompound.getInteger( "instanceID" );

src/main/java/dan200/computercraft/shared/computer/core/ClientComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/core/ClientComputerRegistry.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/core/ComputerFamily.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/core/ComputerRegistry.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/core/IComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -10,16 +10,16 @@ import dan200.computercraft.shared.common.ITerminal;
 
 public interface IComputer extends ITerminal
 {
-    public int getInstanceID();
+    int getInstanceID();
-    public int getID();
+    int getID();
-    public String getLabel();
+    String getLabel();
 
-    public boolean isOn();
+    boolean isOn();
-    public boolean isCursorDisplayed();
+    boolean isCursorDisplayed();
-    public void turnOn();
+    void turnOn();
-    public void shutdown();
+    void shutdown();
-    public void reboot();
+    void reboot();
 
-    public void queueEvent( String event );
+    void queueEvent( String event );
-    public void queueEvent( String event, Object[] arguments );
+    void queueEvent( String event, Object[] arguments );
 }

src/main/java/dan200/computercraft/shared/computer/core/IComputerContainer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -8,5 +8,5 @@ package dan200.computercraft.shared.computer.core;
 
 public interface IComputerContainer
 {
-    public IComputer getComputer();
+    IComputer getComputer();
 }

src/main/java/dan200/computercraft/shared/computer/core/ServerComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/core/ServerComputerRegistry.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com

src/main/java/dan200/computercraft/shared/computer/inventory/ContainerComputer.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com
@@ -12,6 +12,7 @@ import dan200.computercraft.shared.computer.core.IContainerComputer;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.inventory.Container;
 
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 public class ContainerComputer extends Container
@@ -25,7 +26,7 @@ public class ContainerComputer extends Container
     }
     
     @Override
-    public boolean canInteractWith( EntityPlayer player )
+    public boolean canInteractWith( @Nonnull EntityPlayer player )
     {
         return m_computer.isUseableByPlayer( player );
     }

src/main/java/dan200/computercraft/shared/computer/items/ComputerItemFactory.java

@@ -1,4 +1,4 @@
-/**
+/*
  * This file is part of ComputerCraft - http://www.computercraft.info
  * Copyright Daniel Ratcliffe, 2011-2016. Do not distribute without permission.
  * Send enquiries to dratcliffe@gmail.com