Switch to JSpecify annotations

Now, hear me out, what if instead of having three @Nullable annotations,
we had *four*?

I've been wanting to switch away from javax.annoations for a while. The
library has been deprecated for ever and, unlike other @Nullable
annotations, the annotation is attached to the parameter/function
itself, rather than the type.

We use JSpecify rather than one of the alternatives (JetBrains,
CheckerFramework) mostly because it's what NullAway recommends. We keep
CheckerFramework around for @DefaultQualifier, and JB's for @Contract.

There are some ugly changes here — for instance, `@Nullable byte[]` is
replace by `byte @Nullable`, and `@Nullable ILuaMachine.Factory` is
`ILuaMachine.@Nullable Factory`. Ughr, I understand why, but it does not
spark joy :).

buildSrc/src/main/kotlin/cc-tweaked.java-convention.gradle.kts

@@ -84,7 +84,6 @@ sourceSets.all {
 
         options.errorprone {
             check("InvalidBlockTag", CheckSeverity.OFF) // Broken by @cc.xyz
-            check("InvalidParam", CheckSeverity.OFF) // Broken by records.
             check("InlineMeSuggester", CheckSeverity.OFF) // Minecraft uses @Deprecated liberally
             // Too many false positives right now. Maybe we need an indirection for it later on.
             check("ReferenceEquality", CheckSeverity.OFF)

config/checkstyle/checkstyle.xml

@@ -92,7 +92,10 @@ SPDX-License-Identifier: MPL-2.0
         <module name="InvalidJavadocPosition" />
         <module name="JavadocBlockTagLocation" />
         <module name="JavadocMethod"/>
-        <module name="JavadocType"/>
+        <module name="JavadocType">
+            <!-- Seems to complain about @hidden!? -->
+            <property name="allowUnknownTags" value="true" />
+        </module>
         <module name="JavadocStyle">
             <property name="checkHtml" value="false" />
         </module>
@@ -143,7 +146,10 @@ SPDX-License-Identifier: MPL-2.0
         <module name="NoWhitespaceAfter">
             <property name="tokens" value="AT,INC,DEC,UNARY_MINUS,UNARY_PLUS,BNOT,LNOT,DOT,ARRAY_DECLARATOR,INDEX_OP,METHOD_REF" />
         </module>
-        <module name="NoWhitespaceBefore" />
+        <module name="NoWhitespaceBefore">
+            <!-- Allow whitespace before "..." for @Nullable annotations -->
+            <property name="tokens" value="COMMA,SEMI,POST_INC,POST_DEC,LABELED_STAT" />
+        </module>
         <!-- TODO: Decide on an OperatorWrap style. -->
         <module name="ParenPad" />
         <module name="SeparatorWrap">

gradle/libs.versions.toml

@@ -29,9 +29,9 @@ checkerFramework = "3.42.0"
 cobalt = { strictly = "0.9.5" }
 commonsCli = "1.6.0"
 jetbrainsAnnotations = "24.1.0"
-jsr305 = "3.0.2"
+jspecify = "1.0.0"
 jzlib = "1.1.3"
-kotlin = "2.1.0"
+kotlin = "2.1.10"
 kotlin-coroutines = "1.10.1"
 nightConfig = "3.8.1"
 
@@ -58,9 +58,9 @@ jmh = "1.37"
 
 # Build tools
 cctJavadoc = "1.8.3"
-checkstyle = "10.14.1"
-errorProne-core = "2.27.0"
-errorProne-plugin = "3.1.0"
+checkstyle = "10.21.2"
+errorProne-core = "2.36.0"
+errorProne-plugin = "4.1.0"
 fabric-loom = "1.9.2"
 githubRelease = "2.5.2"
 gradleVersions = "0.50.0"
@@ -69,7 +69,7 @@ illuaminate = "0.1.0-74-gf1551d5"
 lwjgl = "3.3.3"
 minotaur = "2.8.7"
 modDevGradle = "2.0.74"
-nullAway = "0.10.25"
+nullAway = "0.12.3"
 shadow = "8.3.1"
 spotless = "6.23.3"
 taskTree = "2.1.1"
@@ -89,7 +89,7 @@ fastutil = { module = "it.unimi.dsi:fastutil", version.ref = "fastutil" }
 forgeSpi = { module = "net.minecraftforge:forgespi", version.ref = "forgeSpi" }
 guava = { module = "com.google.guava:guava", version.ref = "guava" }
 jetbrainsAnnotations = { module = "org.jetbrains:annotations", version.ref = "jetbrainsAnnotations" }
-jsr305 = { module = "com.google.code.findbugs:jsr305", version.ref = "jsr305" }
+jspecify = { module = "org.jspecify:jspecify", version.ref = "jspecify" }
 jzlib = { module = "com.jcraft:jzlib", version.ref = "jzlib" }
 kotlin-coroutines = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version.ref = "kotlin-coroutines" }
 kotlin-platform = { module = "org.jetbrains.kotlin:kotlin-bom", version.ref = "kotlin" }
@@ -178,7 +178,7 @@ taskTree = { id = "com.dorongold.task-tree", version.ref = "taskTree" }
 versionCatalogUpdate = { id = "nl.littlerobots.version-catalog-update", version.ref = "versionCatalogUpdate" }
 
 [bundles]
-annotations = ["jsr305", "checkerFramework", "jetbrainsAnnotations"]
+annotations = ["checkerFramework", "jetbrainsAnnotations", "jspecify"]
 kotlin = ["kotlin-stdlib", "kotlin-coroutines"]
 
 # Minecraft

projects/common-api/src/client/java/dan200/computercraft/api/client/turtle/TurtleUpgradeModeller.java

@@ -12,8 +12,8 @@ import net.minecraft.client.resources.model.ModelResourceLocation;
 import net.minecraft.client.resources.model.UnbakedModel;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Collection;
 import java.util.List;
 

projects/common-api/src/client/java/dan200/computercraft/api/client/turtle/TurtleUpgradeModellers.java

@@ -14,8 +14,7 @@ import net.minecraft.client.Minecraft;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.world.item.ItemStack;
 import org.joml.Matrix4f;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 final class TurtleUpgradeModellers {
     private static final Transformation leftTransform = getMatrixFor(-0.4065f);

projects/common-api/src/client/java/dan200/computercraft/impl/client/ClientPlatformHelper.java

@@ -11,8 +11,7 @@ import net.minecraft.client.resources.model.ModelManager;
 import net.minecraft.client.resources.model.ModelResourceLocation;
 import net.minecraft.resources.ResourceLocation;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 @ApiStatus.Internal
 public interface ClientPlatformHelper {

projects/common-api/src/client/java/dan200/computercraft/impl/client/ComputerCraftAPIClientService.java

@@ -10,8 +10,7 @@ import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleUpgradeSerialiser;
 import dan200.computercraft.impl.Services;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Backing interface for {@link ComputerCraftAPIClient}

projects/common-api/src/main/java/dan200/computercraft/api/ComputerCraftAPI.java

@@ -26,8 +26,7 @@ import net.minecraft.core.Direction;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * The static entry point to the ComputerCraft API.

projects/common-api/src/main/java/dan200/computercraft/api/detail/BasicItemDetailProvider.java

@@ -6,8 +6,8 @@ package dan200.computercraft.api.detail;
 
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;

projects/common-api/src/main/java/dan200/computercraft/api/detail/BlockReference.java

@@ -8,8 +8,7 @@ import net.minecraft.core.BlockPos;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A reference to a block in the world, used by block detail providers.

projects/common-api/src/main/java/dan200/computercraft/api/lua/IComputerSystem.java

@@ -9,8 +9,7 @@ import dan200.computercraft.api.peripheral.IComputerAccess;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * An interface passed to {@link ILuaAPIFactory} in order to provide additional information

projects/common-api/src/main/java/dan200/computercraft/api/lua/ILuaAPIFactory.java

@@ -5,8 +5,7 @@
 package dan200.computercraft.api.lua;
 
 import dan200.computercraft.api.ComputerCraftAPI;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Construct an {@link ILuaAPI} for a computer.

projects/common-api/src/main/java/dan200/computercraft/api/media/IMedia.java

@@ -12,8 +12,7 @@ import net.minecraft.server.level.ServerLevel;
 import net.minecraft.sounds.SoundEvent;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Represents an item that can be placed in a disk drive and used by a Computer.

projects/common-api/src/main/java/dan200/computercraft/api/media/MediaProvider.java

@@ -5,8 +5,7 @@
 package dan200.computercraft.api.media;
 
 import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * This interface is used to provide {@link IMedia} implementations for {@link ItemStack}.

projects/common-api/src/main/java/dan200/computercraft/api/media/PrintoutContents.java

@@ -6,8 +6,8 @@ package dan200.computercraft.api.media;
 
 import dan200.computercraft.impl.ComputerCraftAPIService;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.stream.Stream;
 
 /**

projects/common-api/src/main/java/dan200/computercraft/api/pocket/IPocketAccess.java

@@ -14,8 +14,8 @@ import net.minecraft.world.entity.Entity;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.phys.Vec3;
 import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Map;
 
 /**

projects/common-api/src/main/java/dan200/computercraft/api/pocket/IPocketUpgrade.java

@@ -7,8 +7,7 @@ package dan200.computercraft.api.pocket;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.upgrades.UpgradeBase;
 import net.minecraft.world.level.Level;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A peripheral which can be equipped to the back side of a pocket computer.

projects/common-api/src/main/java/dan200/computercraft/api/turtle/ITurtleAccess.java

@@ -17,8 +17,7 @@ import net.minecraft.world.Container;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * The interface passed to turtle by turtles, providing methods that they can call.

projects/common-api/src/main/java/dan200/computercraft/api/turtle/ITurtleUpgrade.java

@@ -9,8 +9,8 @@ import dan200.computercraft.api.upgrades.UpgradeBase;
 import net.minecraft.core.Direction;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.world.item.Items;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.function.BiFunction;
 
 /**

projects/common-api/src/main/java/dan200/computercraft/api/turtle/TurtleCommandResult.java

@@ -5,8 +5,7 @@
 package dan200.computercraft.api.turtle;
 
 import net.minecraft.core.Direction;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Used to indicate the result of executing a turtle command.
@@ -60,9 +59,9 @@ public final class TurtleCommandResult {
 
     private final boolean success;
     private final @Nullable String errorMessage;
-    private final @Nullable Object[] results;
+    private final @Nullable Object @Nullable [] results;
 
-    private TurtleCommandResult(boolean success, @Nullable String errorMessage, @Nullable Object[] results) {
+    private TurtleCommandResult(boolean success, @Nullable String errorMessage, @Nullable Object @Nullable [] results) {
         this.success = success;
         this.errorMessage = errorMessage;
         this.results = results;
@@ -92,8 +91,7 @@ public final class TurtleCommandResult {
      *
      * @return The command's result, or {@code null} if it was a failure.
      */
-    @Nullable
-    public Object[] getResults() {
+    public @Nullable Object @Nullable [] getResults() {
         return results;
     }
 }

projects/common-api/src/main/java/dan200/computercraft/api/turtle/TurtleUpgradeDataProvider.java

@@ -18,8 +18,8 @@ import net.minecraft.world.entity.ai.attributes.Attributes;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.block.Block;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.function.Consumer;
 
 /**

projects/common-api/src/main/java/dan200/computercraft/api/upgrades/UpgradeData.java

@@ -9,8 +9,7 @@ import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.world.item.ItemStack;
 import org.jetbrains.annotations.Contract;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * An upgrade (i.e. a {@link ITurtleUpgrade}) and its current upgrade data.

projects/common-api/src/main/java/dan200/computercraft/api/upgrades/UpgradeDataProvider.java

@@ -19,8 +19,8 @@ import net.minecraft.data.PackOutput;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.Item;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.*;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Consumer;

projects/common-api/src/main/java/dan200/computercraft/impl/ComputerCraftAPIService.java

@@ -28,8 +28,7 @@ import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Backing interface for {@link ComputerCraftAPI}

projects/common-api/src/main/java/dan200/computercraft/impl/PlatformHelper.java

@@ -12,8 +12,7 @@ import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
 import org.jetbrains.annotations.ApiStatus;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Abstraction layer for Forge and Fabric. See implementations for more details.

projects/common-api/src/main/java/dan200/computercraft/impl/ServiceException.java

@@ -5,8 +5,8 @@
 package dan200.computercraft.impl;
 
 import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.io.Serial;
 
 /**

projects/common-api/src/main/java/dan200/computercraft/impl/Services.java

@@ -5,8 +5,8 @@
 package dan200.computercraft.impl;
 
 import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ServiceLoader;
 import java.util.stream.Collectors;
 

projects/common/src/client/java/dan200/computercraft/client/ClientHooks.java

@@ -38,8 +38,8 @@ import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.BlockHitResult;
 import net.minecraft.world.phys.HitResult;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.function.Consumer;
 
 /**

projects/common/src/client/java/dan200/computercraft/client/ClientRegistry.java

@@ -46,8 +46,8 @@ import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.ItemLike;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.io.File;
 import java.io.IOException;
 import java.util.function.BiConsumer;

projects/common/src/client/java/dan200/computercraft/client/ClientTableFormatter.java

@@ -15,8 +15,8 @@ import net.minecraft.client.gui.components.ChatComponent;
 import net.minecraft.network.chat.Component;
 import net.minecraft.util.Mth;
 import org.apache.commons.lang3.StringUtils;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Objects;
 
 /**

projects/common/src/client/java/dan200/computercraft/client/gui/AbstractComputerScreen.java

@@ -26,11 +26,11 @@ import net.minecraft.client.gui.screens.inventory.AbstractContainerScreen;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.entity.player.Inventory;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.glfw.GLFW;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.file.Files;

projects/common/src/client/java/dan200/computercraft/client/gui/GuiSprites.java

@@ -11,8 +11,8 @@ import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.client.renderer.texture.TextureManager;
 import net.minecraft.client.resources.TextureAtlasHolder;
 import net.minecraft.resources.ResourceLocation;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Objects;
 import java.util.stream.Stream;
 

projects/common/src/client/java/dan200/computercraft/client/gui/NoTermComputerScreen.java

@@ -15,9 +15,9 @@ import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.client.gui.screens.inventory.MenuAccess;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.entity.player.Inventory;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.glfw.GLFW;
 
-import javax.annotation.Nullable;
 import java.util.Objects;
 
 import static dan200.computercraft.core.util.Nullability.assertNonNull;

projects/common/src/client/java/dan200/computercraft/client/gui/OptionScreen.java

@@ -12,8 +12,8 @@ import net.minecraft.client.gui.components.MultiLineLabel;
 import net.minecraft.client.gui.screens.Screen;
 import net.minecraft.network.chat.Component;
 import net.minecraft.resources.ResourceLocation;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.List;
 
 import static dan200.computercraft.core.util.Nullability.assertNonNull;

projects/common/src/client/java/dan200/computercraft/client/gui/PrintoutScreen.java

@@ -149,6 +149,7 @@ public final class PrintoutScreen extends AbstractContainerScreen<PrintoutMenu>
         // Skip rendering labels.
     }
 
+    @SuppressWarnings("ArrayRecordComponent")
     record PrintoutInfo(int pages, boolean book, TextBuffer[] text, TextBuffer[] colour) {
         public static final PrintoutInfo DEFAULT;
 

projects/common/src/client/java/dan200/computercraft/client/gui/widgets/DynamicImageButton.java

@@ -12,8 +12,8 @@ import net.minecraft.client.gui.components.Button;
 import net.minecraft.client.gui.components.Tooltip;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.network.chat.Component;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.function.Supplier;
 
 /**

projects/common/src/client/java/dan200/computercraft/client/model/turtle/ModelTransformer.java

@@ -13,8 +13,8 @@ import net.minecraft.client.resources.model.BakedModel;
 import net.minecraft.core.Direction;
 import org.joml.Matrix4f;
 import org.joml.Vector4f;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 

projects/common/src/client/java/dan200/computercraft/client/model/turtle/TurtleModelParts.java

@@ -20,8 +20,8 @@ import net.minecraft.client.Minecraft;
 import net.minecraft.client.resources.model.BakedModel;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;

projects/common/src/client/java/dan200/computercraft/client/platform/ClientNetworkContextImpl.java

@@ -26,8 +26,8 @@ import net.minecraft.resources.ResourceLocation;
 import net.minecraft.sounds.SoundEvent;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.level.Level;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.UUID;
 
 /**

projects/common/src/client/java/dan200/computercraft/client/platform/ClientPlatformHelper.java

@@ -13,8 +13,7 @@ import net.minecraft.core.BlockPos;
 import net.minecraft.network.protocol.Packet;
 import net.minecraft.network.protocol.game.ServerGamePacketListener;
 import net.minecraft.sounds.SoundEvent;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public interface ClientPlatformHelper extends dan200.computercraft.impl.client.ClientPlatformHelper {
     static ClientPlatformHelper get() {
@@ -39,7 +38,7 @@ public interface ClientPlatformHelper extends dan200.computercraft.impl.client.C
      * @param overlayLight  The current overlay light.
      * @param tints         Block colour tints to apply to the model.
      */
-    void renderBakedModel(PoseStack transform, MultiBufferSource buffers, BakedModel model, int lightmapCoord, int overlayLight, @Nullable int[] tints);
+    void renderBakedModel(PoseStack transform, MultiBufferSource buffers, BakedModel model, int lightmapCoord, int overlayLight, int @Nullable [] tints);
 
     /**
      * Play a record at a particular position.

projects/common/src/client/java/dan200/computercraft/client/pocket/ClientPocketComputers.java

@@ -10,8 +10,8 @@ import dan200.computercraft.shared.computer.terminal.TerminalState;
 import dan200.computercraft.shared.network.client.PocketComputerDataMessage;
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.UUID;

projects/common/src/client/java/dan200/computercraft/client/pocket/PocketComputerData.java

@@ -8,8 +8,7 @@ import dan200.computercraft.shared.computer.core.ComputerState;
 import dan200.computercraft.shared.computer.terminal.NetworkedTerminal;
 import dan200.computercraft.shared.computer.terminal.TerminalState;
 import dan200.computercraft.shared.pocket.core.PocketServerComputer;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Clientside data about a pocket computer.

projects/common/src/client/java/dan200/computercraft/client/render/ModelRenderer.java

@@ -14,8 +14,8 @@ import net.minecraft.client.renderer.entity.ItemRenderer;
 import net.minecraft.client.resources.model.BakedModel;
 import net.minecraft.world.item.ItemStack;
 import org.joml.Vector4f;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.List;
 
 /**
@@ -39,7 +39,7 @@ public final class ModelRenderer {
      * @param overlayLight  The current overlay light.
      * @param tints         Block colour tints to apply to the model.
      */
-    public static void renderQuads(PoseStack transform, VertexConsumer buffer, List<BakedQuad> quads, int lightmapCoord, int overlayLight, @Nullable int[] tints) {
+    public static void renderQuads(PoseStack transform, VertexConsumer buffer, List<BakedQuad> quads, int lightmapCoord, int overlayLight, int @Nullable [] tints) {
         var matrix = transform.last();
         var inverted = matrix.pose().determinant() < 0;
 

projects/common/src/client/java/dan200/computercraft/client/render/RenderTypes.java

@@ -16,8 +16,8 @@ import net.minecraft.client.renderer.RenderType;
 import net.minecraft.client.renderer.ShaderInstance;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.packs.resources.ResourceProvider;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.io.IOException;
 import java.util.Objects;
 import java.util.function.BiConsumer;

projects/common/src/client/java/dan200/computercraft/client/render/TurtleBlockEntityRenderer.java

@@ -23,8 +23,7 @@ import net.minecraft.client.resources.model.BakedModel;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.phys.BlockHitResult;
 import net.minecraft.world.phys.HitResult;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBlockEntity> {
     private static final ResourceLocation COLOUR_TURTLE_MODEL = new ResourceLocation(ComputerCraftAPI.MOD_ID, "block/turtle_colour");
@@ -127,7 +126,7 @@ public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBloc
         transform.popPose();
     }
 
-    private void renderModel(PoseStack transform, MultiBufferSource buffers, int lightmapCoord, int overlayLight, ResourceLocation modelLocation, @Nullable int[] tints) {
+    private void renderModel(PoseStack transform, MultiBufferSource buffers, int lightmapCoord, int overlayLight, ResourceLocation modelLocation, int @Nullable [] tints) {
         var modelManager = Minecraft.getInstance().getItemRenderer().getItemModelShaper().getModelManager();
         renderModel(transform, buffers, lightmapCoord, overlayLight, ClientPlatformHelper.get().getModel(modelManager, modelLocation), tints);
     }
@@ -143,7 +142,7 @@ public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBloc
      * @param tints         Tints for the quads, as an array of RGB values.
      * @see net.minecraft.client.renderer.block.ModelBlockRenderer#renderModel
      */
-    private void renderModel(PoseStack transform, MultiBufferSource renderer, int lightmapCoord, int overlayLight, BakedModel model, @Nullable int[] tints) {
+    private void renderModel(PoseStack transform, MultiBufferSource renderer, int lightmapCoord, int overlayLight, BakedModel model, int @Nullable [] tints) {
         ClientPlatformHelper.get().renderBakedModel(transform, renderer, model, lightmapCoord, overlayLight, tints);
     }
 

projects/common/src/client/java/dan200/computercraft/client/render/monitor/MonitorBlockEntityRenderer.java

@@ -27,11 +27,11 @@ import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
 import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
 import org.joml.Matrix3f;
 import org.joml.Matrix4f;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.opengl.GL11;
 import org.lwjgl.opengl.GL20;
 import org.lwjgl.opengl.GL31;
 
-import javax.annotation.Nullable;
 import java.nio.ByteBuffer;
 import java.util.function.Consumer;
 

projects/common/src/client/java/dan200/computercraft/client/render/monitor/MonitorRenderState.java

@@ -11,12 +11,12 @@ import dan200.computercraft.client.render.vbo.DirectVertexBuffer;
 import dan200.computercraft.shared.peripheral.monitor.ClientMonitor;
 import dan200.computercraft.shared.peripheral.monitor.MonitorRenderer;
 import net.minecraft.core.BlockPos;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.opengl.GL11;
 import org.lwjgl.opengl.GL15;
 import org.lwjgl.opengl.GL30;
 import org.lwjgl.opengl.GL31;
 
-import javax.annotation.Nullable;
 import java.util.HashSet;
 import java.util.Set;
 

projects/common/src/client/java/dan200/computercraft/client/render/monitor/MonitorTextureBufferShader.java

@@ -14,12 +14,12 @@ import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.core.util.Colour;
 import net.minecraft.client.renderer.ShaderInstance;
 import net.minecraft.server.packs.resources.ResourceProvider;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.opengl.GL13;
 import org.lwjgl.opengl.GL31;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 

projects/common/src/client/java/dan200/computercraft/client/sound/DfpwmStream.java

@@ -10,9 +10,9 @@ import dan200.computercraft.shared.peripheral.speaker.SpeakerPeripheral;
 import dan200.computercraft.shared.peripheral.speaker.SpeakerPosition;
 import net.minecraft.client.sounds.AudioStream;
 import net.minecraft.client.sounds.SoundEngine;
+import org.jspecify.annotations.Nullable;
 import org.lwjgl.BufferUtils;
 
-import javax.annotation.Nullable;
 import javax.sound.sampled.AudioFormat;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;

projects/common/src/client/java/dan200/computercraft/client/sound/SpeakerInstance.java

@@ -10,8 +10,7 @@ import dan200.computercraft.shared.peripheral.speaker.EncodedAudio;
 import dan200.computercraft.shared.peripheral.speaker.SpeakerPosition;
 import net.minecraft.client.Minecraft;
 import net.minecraft.resources.ResourceLocation;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * An instance of a speaker, which is either playing a {@link DfpwmStream} stream or a normal sound.

projects/common/src/client/java/dan200/computercraft/client/sound/SpeakerSound.java

@@ -16,8 +16,8 @@ import net.minecraft.client.sounds.SoundBufferLibrary;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.sounds.SoundSource;
 import net.minecraft.world.entity.Entity;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.concurrent.CompletableFuture;
 
 /**

projects/common/src/client/java/dan200/computercraft/client/turtle/TurtleModemModeller.java

@@ -11,7 +11,7 @@ import dan200.computercraft.api.turtle.ITurtleAccess;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.shared.turtle.upgrades.TurtleModem;
 import net.minecraft.resources.ResourceLocation;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 import java.util.Collection;
 import java.util.List;

projects/common/src/datagen/java/dan200/computercraft/data/RecipeWrapper.java

@@ -10,8 +10,8 @@ import net.minecraft.nbt.CompoundTag;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.world.item.crafting.RecipeSerializer;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Consumer;

projects/common/src/examples/java/com/example/examplemod/ExampleAPI.java

@@ -6,7 +6,7 @@ import dan200.computercraft.api.lua.Coerced;
 import dan200.computercraft.api.lua.ILuaAPI;
 import dan200.computercraft.api.lua.LuaFunction;
 import dan200.computercraft.api.turtle.ITurtleAccess;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * An example API that will be available on every turtle. This demonstrates both registering an API, and how to write

projects/common/src/examples/java/com/example/examplemod/peripheral/BrewingStandPeripheral.java

@@ -3,7 +3,7 @@ package com.example.examplemod.peripheral;
 import dan200.computercraft.api.lua.LuaFunction;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import net.minecraft.world.level.block.entity.BrewingStandBlockEntity;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A peripheral that adds a {@code getFuel()} method to brewing stands. This demonstrates the usage of

projects/common/src/examples/java/com/example/examplemod/peripheral/ComputerTrackingPeripheral.java

@@ -4,7 +4,7 @@ import dan200.computercraft.api.lua.LuaFunction;
 import dan200.computercraft.api.peripheral.AttachedComputerSet;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IPeripheral;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A peripheral that tracks what computers it is attached to.

projects/common/src/main/java/dan200/computercraft/impl/AbstractComputerCraftAPI.java

@@ -36,8 +36,8 @@ import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;

projects/common/src/main/java/dan200/computercraft/impl/MediaProviders.java

@@ -7,10 +7,10 @@ package dan200.computercraft.impl;
 import dan200.computercraft.api.media.IMedia;
 import dan200.computercraft.api.media.MediaProvider;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.util.LinkedHashSet;
 import java.util.Objects;
 import java.util.Set;

projects/common/src/main/java/dan200/computercraft/impl/UpgradeManager.java

@@ -18,10 +18,10 @@ import net.minecraft.server.packs.resources.SimpleJsonResourceReloadListener;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.util.profiling.ProfilerFiller;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;

projects/common/src/main/java/dan200/computercraft/impl/network/wired/InvariantChecker.java

@@ -5,11 +5,10 @@
 package dan200.computercraft.impl.network.wired;
 
 import org.jetbrains.annotations.Contract;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
-
 /**
  * Verifies certain elements of a network are well-formed.
  * <p>

projects/common/src/main/java/dan200/computercraft/impl/network/wired/NodeSet.java

@@ -5,8 +5,8 @@
 package dan200.computercraft.impl.network.wired;
 
 import dan200.computercraft.api.network.wired.WiredNode;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Objects;
 
 /**

projects/common/src/main/java/dan200/computercraft/impl/network/wired/WiredNodeImpl.java

@@ -11,8 +11,8 @@ import dan200.computercraft.api.network.wired.WiredNetwork;
 import dan200.computercraft.api.network.wired.WiredNode;
 import dan200.computercraft.api.network.wired.WiredSender;
 import dan200.computercraft.api.peripheral.IPeripheral;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;

projects/common/src/main/java/dan200/computercraft/shared/CommonHooks.java

@@ -30,8 +30,8 @@ import net.minecraft.world.level.storage.loot.BuiltInLootTables;
 import net.minecraft.world.level.storage.loot.LootPool;
 import net.minecraft.world.level.storage.loot.entries.LootTableReference;
 import net.minecraft.world.level.storage.loot.providers.number.ConstantValue;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Set;
 import java.util.function.BiConsumer;
 
@@ -101,7 +101,7 @@ public final class CommonHooks {
         BuiltInLootTables.VILLAGE_CARTOGRAPHER
     );
 
-    public static @Nullable LootPool.Builder getExtraLootPool(ResourceLocation lootTable) {
+    public static LootPool.@Nullable Builder getExtraLootPool(ResourceLocation lootTable) {
         if (!lootTable.getNamespace().equals("minecraft") || !TREASURE_DISK_LOOT_TABLES.contains(lootTable)) {
             return null;
         }

projects/common/src/main/java/dan200/computercraft/shared/command/CommandComputerCraft.java

@@ -34,8 +34,8 @@ import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.phys.Vec3;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.io.File;
 import java.util.*;
 

projects/common/src/main/java/dan200/computercraft/shared/command/arguments/ComputerSelector.java

@@ -22,8 +22,8 @@ import net.minecraft.network.chat.ComponentContents;
 import net.minecraft.network.chat.MutableComponent;
 import net.minecraft.world.phys.AABB;
 import net.minecraft.world.phys.Vec3;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.*;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Function;
@@ -43,11 +43,11 @@ public record ComputerSelector(
     @Nullable String label,
     @Nullable ComputerFamily family,
     @Nullable AABB bounds,
-    @Nullable MinMaxBounds.Doubles range
+    MinMaxBounds.@Nullable Doubles range
 ) {
     private static final ComputerSelector all = new ComputerSelector("@c[]", OptionalInt.empty(), null, OptionalInt.empty(), null, null, null, null);
 
-    private static UuidArgument uuidArgument = UuidArgument.uuid();
+    private static final UuidArgument uuidArgument = UuidArgument.uuid();
 
     /**
      * A {@link ComputerSelector} which matches all computers.
@@ -279,7 +279,7 @@ public record ComputerSelector(
         private @Nullable String label;
         private @Nullable ComputerFamily family;
         private @Nullable AABB bounds;
-        private @Nullable MinMaxBounds.Doubles range;
+        private MinMaxBounds.@Nullable Doubles range;
     }
 
     private static final Map<String, Option> options;

projects/common/src/main/java/dan200/computercraft/shared/command/builder/CommandBuilder.java

@@ -12,8 +12,8 @@ import com.mojang.brigadier.context.CommandContext;
 import com.mojang.brigadier.tree.CommandNode;
 import dan200.computercraft.shared.command.arguments.RepeatArgumentType;
 import net.minecraft.commands.CommandSourceStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Predicate;

projects/common/src/main/java/dan200/computercraft/shared/command/builder/HelpingArgumentBuilder.java

@@ -14,8 +14,8 @@ import net.minecraft.ChatFormatting;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.network.chat.ClickEvent;
 import net.minecraft.network.chat.Component;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.function.Predicate;

projects/common/src/main/java/dan200/computercraft/shared/command/text/ChatHelpers.java

@@ -12,8 +12,7 @@ import net.minecraft.network.chat.ClickEvent;
 import net.minecraft.network.chat.Component;
 import net.minecraft.network.chat.HoverEvent;
 import net.minecraft.network.chat.MutableComponent;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Various helpers for building chat messages.

projects/common/src/main/java/dan200/computercraft/shared/command/text/ServerTableFormatter.java

@@ -7,8 +7,7 @@ package dan200.computercraft.shared.command.text;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.network.chat.Component;
 import org.apache.commons.lang3.StringUtils;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public class ServerTableFormatter implements TableFormatter {
     private final CommandSourceStack source;

projects/common/src/main/java/dan200/computercraft/shared/command/text/TableBuilder.java

@@ -11,15 +11,15 @@ import dan200.computercraft.shared.network.server.ServerNetworking;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.network.chat.Component;
 import net.minecraft.server.level.ServerPlayer;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 
 public class TableBuilder {
     private final String id;
     private int columns = -1;
-    private final @Nullable Component[] headers;
+    private final Component @Nullable [] headers;
     private final ArrayList<Component[]> rows = new ArrayList<>();
     private int additional;
 
@@ -72,8 +72,7 @@ public class TableBuilder {
         return columns;
     }
 
-    @Nullable
-    public Component[] getHeaders() {
+    public Component @Nullable [] getHeaders() {
         return headers;
     }
 

projects/common/src/main/java/dan200/computercraft/shared/command/text/TableFormatter.java

@@ -7,8 +7,7 @@ package dan200.computercraft.shared.command.text;
 import net.minecraft.ChatFormatting;
 import net.minecraft.network.chat.Component;
 import org.apache.commons.lang3.StringUtils;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 import static dan200.computercraft.shared.command.text.ChatHelpers.coloured;
 

projects/common/src/main/java/dan200/computercraft/shared/common/HorizontalContainerBlock.java

@@ -23,8 +23,7 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.block.state.properties.BlockStateProperties;
 import net.minecraft.world.level.block.state.properties.DirectionProperty;
 import net.minecraft.world.phys.BlockHitResult;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A block which has a container and can be placed in a horizontal direction.

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java

@@ -36,8 +36,8 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.storage.loot.LootParams;
 import net.minecraft.world.level.storage.loot.parameters.LootContextParams;
 import net.minecraft.world.phys.BlockHitResult;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.List;
 
 public abstract class AbstractComputerBlock<T extends AbstractComputerBlockEntity> extends HorizontalDirectionalBlock implements IBundledRedstoneBlock, EntityBlock {

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java

@@ -34,8 +34,8 @@ import net.minecraft.world.level.block.entity.BaseContainerBlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Objects;
 import java.util.UUID;
 

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlock.java

@@ -17,8 +17,7 @@ import net.minecraft.world.level.block.state.StateDefinition;
 import net.minecraft.world.level.block.state.properties.BlockStateProperties;
 import net.minecraft.world.level.block.state.properties.DirectionProperty;
 import net.minecraft.world.level.block.state.properties.EnumProperty;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public class ComputerBlock<T extends ComputerBlockEntity> extends AbstractComputerBlock<T> {
     public static final EnumProperty<ComputerState> STATE = EnumProperty.create("state", ComputerState.class);

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java

@@ -20,8 +20,7 @@ import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public class ComputerBlockEntity extends AbstractComputerBlockEntity {
     private @Nullable IPeripheral peripheral;

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

@@ -7,8 +7,7 @@ package dan200.computercraft.shared.computer.blocks;
 import dan200.computercraft.api.lua.LuaFunction;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.apis.OSAPI;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A computer or turtle wrapped as a peripheral.

projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerSystem.java

@@ -13,8 +13,8 @@ import dan200.computercraft.core.apis.IAPIEnvironment;
 import dan200.computercraft.core.computer.ApiLifecycle;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.Map;
 
 /**

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

@@ -29,8 +29,8 @@ import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.UUID;
@@ -214,7 +214,7 @@ public class ServerComputer implements ComputerEnvironment, ComputerEvents.Recei
     }
 
     @Override
-    public final void queueEvent(String event, @Nullable Object[] arguments) {
+    public final void queueEvent(String event, @Nullable Object @Nullable [] arguments) {
         computer.queueEvent(event, arguments);
     }
 

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

@@ -6,8 +6,8 @@ package dan200.computercraft.shared.computer.core;
 
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.*;
 
 public class ServerComputerRegistry {

projects/common/src/main/java/dan200/computercraft/shared/computer/core/ServerContext.java

@@ -26,10 +26,10 @@ import dan200.computercraft.shared.util.IDAssigner;
 import net.minecraft.SharedConstants;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.level.storage.LevelResource;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.io.InputStream;
 import java.nio.file.Path;
 import java.util.Objects;

projects/common/src/main/java/dan200/computercraft/shared/computer/inventory/AbstractComputerMenu.java

@@ -21,8 +21,8 @@ import net.minecraft.world.inventory.ContainerData;
 import net.minecraft.world.inventory.MenuType;
 import net.minecraft.world.inventory.SimpleContainerData;
 import net.minecraft.world.item.ItemStack;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.function.Predicate;
 
 public abstract class AbstractComputerMenu extends AbstractContainerMenu implements ComputerMenu {

projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java

@@ -16,8 +16,8 @@ import net.minecraft.world.item.BlockItem;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.TooltipFlag;
 import net.minecraft.world.level.Level;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.List;
 
 public abstract class AbstractComputerItem extends BlockItem implements IComputerItem, IMedia {

projects/common/src/main/java/dan200/computercraft/shared/computer/items/CommandComputerItem.java

@@ -10,7 +10,7 @@ import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.context.BlockPlaceContext;
 import net.minecraft.world.level.block.state.BlockState;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A {@link ComputerItem} which prevents players placing it without permission.

projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItem.java

@@ -8,8 +8,7 @@ import dan200.computercraft.shared.computer.blocks.ComputerBlock;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public class ComputerItem extends AbstractComputerItem {
     public ComputerItem(ComputerBlock<?> block, Properties settings) {

projects/common/src/main/java/dan200/computercraft/shared/computer/items/IComputerItem.java

@@ -6,8 +6,7 @@ package dan200.computercraft.shared.computer.items;
 
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 public interface IComputerItem {
     String NBT_ID = "ComputerId";

projects/common/src/main/java/dan200/computercraft/shared/computer/menu/ServerInputState.java

@@ -19,10 +19,10 @@ import it.unimi.dsi.fastutil.ints.IntSet;
 import net.minecraft.network.chat.Component;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.inventory.AbstractContainerMenu;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.nio.ByteBuffer;
 import java.util.List;
 import java.util.UUID;

projects/common/src/main/java/dan200/computercraft/shared/computer/metrics/ComputerMBean.java

@@ -14,10 +14,10 @@ import dan200.computercraft.shared.computer.metrics.basic.AggregatedMetric;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import net.minecraft.server.MinecraftServer;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import javax.management.*;
 import java.lang.management.ManagementFactory;
 import java.util.ArrayList;

projects/common/src/main/java/dan200/computercraft/shared/computer/metrics/basic/BasicComputerMetricsObserver.java

@@ -5,12 +5,12 @@
 package dan200.computercraft.shared.computer.metrics.basic;
 
 import com.google.common.collect.MapMaker;
+import com.google.errorprone.annotations.concurrent.GuardedBy;
 import dan200.computercraft.core.metrics.Metric;
 import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.computer.metrics.ComputerMetricsObserver;
 import dan200.computercraft.shared.computer.metrics.GlobalMetrics;
 
-import javax.annotation.concurrent.GuardedBy;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;

projects/common/src/main/java/dan200/computercraft/shared/computer/metrics/basic/ComputerMetrics.java

@@ -6,8 +6,8 @@ package dan200.computercraft.shared.computer.metrics.basic;
 
 import dan200.computercraft.core.metrics.Metric;
 import dan200.computercraft.shared.computer.core.ServerComputer;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.lang.ref.WeakReference;
 import java.util.Arrays;
 

projects/common/src/main/java/dan200/computercraft/shared/computer/terminal/TerminalState.java

@@ -6,8 +6,7 @@ package dan200.computercraft.shared.computer.terminal;
 
 import net.minecraft.network.FriendlyByteBuf;
 import org.jetbrains.annotations.Contract;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A snapshot of a terminal's state.

projects/common/src/main/java/dan200/computercraft/shared/computer/upload/FileUpload.java

@@ -4,10 +4,10 @@
 
 package dan200.computercraft.shared.computer.upload;
 
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.nio.ByteBuffer;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
@@ -52,8 +52,7 @@ public class FileUpload {
         return digest != null && Arrays.equals(checksum, digest);
     }
 
-    @Nullable
-    public static byte[] getDigest(ByteBuffer bytes) {
+    public static byte @Nullable [] getDigest(ByteBuffer bytes) {
         try {
             var digest = MessageDigest.getInstance("SHA-256");
             digest.update(bytes.duplicate());

projects/common/src/main/java/dan200/computercraft/shared/config/ConfigFile.java

@@ -5,9 +5,9 @@
 package dan200.computercraft.shared.config;
 
 import com.google.common.base.Splitter;
+import com.google.errorprone.annotations.OverridingMethodsMustInvokeSuper;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
-import javax.annotation.OverridingMethodsMustInvokeSuper;
 import java.nio.file.Path;
 import java.util.*;
 import java.util.function.Predicate;

projects/common/src/main/java/dan200/computercraft/shared/config/ConfigSpec.java

@@ -16,8 +16,8 @@ import dan200.computercraft.shared.platform.PlatformHelper;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.core.Filter;
 import org.apache.logging.log4j.core.filter.MarkerFilter;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.nio.file.Path;
 import java.util.List;
 import java.util.concurrent.TimeUnit;

projects/common/src/main/java/dan200/computercraft/shared/config/ProxyPasswordConfig.java

@@ -5,10 +5,10 @@
 package dan200.computercraft.shared.config;
 
 import dan200.computercraft.core.CoreConfig;
+import org.jspecify.annotations.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.annotation.Nullable;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;

projects/common/src/main/java/dan200/computercraft/shared/container/BasicWorldlyContainer.java

@@ -7,8 +7,7 @@ package dan200.computercraft.shared.container;
 import net.minecraft.core.Direction;
 import net.minecraft.world.WorldlyContainer;
 import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * A basic implementation of {@link WorldlyContainer} which operates on a {@linkplain #getContents() list of stacks}.

projects/common/src/main/java/dan200/computercraft/shared/details/ItemDetails.java

@@ -13,8 +13,8 @@ import net.minecraft.network.chat.Component;
 import net.minecraft.world.item.EnchantedBookItem;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.enchantment.EnchantmentHelper;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.*;
 
 /**

projects/common/src/main/java/dan200/computercraft/shared/integration/PermissionRegistry.java

@@ -4,13 +4,13 @@
 
 package dan200.computercraft.shared.integration;
 
+import com.google.errorprone.annotations.OverridingMethodsMustInvokeSuper;
 import com.mojang.brigadier.builder.ArgumentBuilder;
 import dan200.computercraft.shared.command.CommandComputerCraft;
 import dan200.computercraft.shared.command.UserLevel;
 import dan200.computercraft.shared.platform.RegistrationHelper;
 import net.minecraft.commands.CommandSourceStack;
 
-import javax.annotation.OverridingMethodsMustInvokeSuper;
 import java.util.Optional;
 import java.util.ServiceLoader;
 import java.util.function.Predicate;

projects/common/src/main/java/dan200/computercraft/shared/integration/UpgradeRecipeGenerator.java

@@ -22,8 +22,8 @@ import net.minecraft.world.item.crafting.CraftingBookCategory;
 import net.minecraft.world.item.crafting.CraftingRecipe;
 import net.minecraft.world.item.crafting.Ingredient;
 import net.minecraft.world.item.crafting.ShapedRecipe;
+import org.jspecify.annotations.Nullable;
 
-import javax.annotation.Nullable;
 import java.util.*;
 import java.util.function.Function;
 

projects/common/src/main/java/dan200/computercraft/shared/lectern/CustomLecternBlock.java

@@ -28,7 +28,7 @@ import net.minecraft.world.level.block.entity.BlockEntityTicker;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.BlockHitResult;
-import org.jetbrains.annotations.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Extends {@link LecternBlock} with support for {@linkplain PrintoutItem printouts}.