Project wide syntax/annotation cleanup (#4238)

Co-authored-by: Konicai <71294714+Konicai@users.noreply.github.com>

CONTRIBUTING.md

@@ -33,18 +33,14 @@ public class LongClassName {
         }
 
         switch (value) {
-            case 0:
+            case 0 -> stuff();
-                stuff();
+            case 1 -> differentStuff();
-                break;
-            case 1:
-                differentStuff();
-                break;
         }
     }
 }
 ```
 
-Make sure to comment your code where possible.
+Make sure to comment your code where possible. To mark nullable methods, use `@Nullable` (and subsequently, `@NonNull`) from the `org.checkerframework.checker.nullness.qual` package.
 
 The nature of our software requires a lot of arrays and maps to be stored - where possible, use Fastutil's specialized maps. For example, if you're storing block state translations, use an `Int2IntMap`.
 

ap/src/main/java/org/geysermc/geyser/processor/ClassProcessor.java

@@ -25,6 +25,8 @@
 
 package org.geysermc.geyser.processor;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
+
 import javax.annotation.processing.AbstractProcessor;
 import javax.annotation.processing.ProcessingEnvironment;
 import javax.annotation.processing.RoundEnvironment;
@@ -159,7 +161,7 @@ public class ClassProcessor extends AbstractProcessor {
         this.processingEnv.getMessager().printMessage(Diagnostic.Kind.NOTE, "Completed processing for " + this.annotationClassName);
     }
 
-    private BufferedReader createReader() throws IOException {
+    private @Nullable BufferedReader createReader() throws IOException {
         if (this.outputPath != null) {
             this.processingEnv.getMessager().printMessage(Diagnostic.Kind.NOTE, "Reading existing " + this.annotationClassName + " list from " + this.outputPath);
             return Files.newBufferedReader(this.outputPath);

api/src/main/java/org/geysermc/geyser/api/GeyserApi.java

@@ -77,6 +77,7 @@ public interface GeyserApi extends GeyserApiBase {
      * @param apiClass the builder class
      * @param <R> the implementation type
      * @param <T> the API type
+     * @throws IllegalArgumentException if there is no provider for the specified API class
      * @return the builder instance
      */
     @NonNull

api/src/main/java/org/geysermc/geyser/api/bedrock/camera/CameraShake.java

@@ -27,5 +27,5 @@ package org.geysermc.geyser.api.bedrock.camera;
 
 public enum CameraShake {
     POSITIONAL,
-    ROTATIONAL;
+    ROTATIONAL
 }

api/src/main/java/org/geysermc/geyser/api/block/custom/component/PlacementConditions.java

@@ -25,11 +25,11 @@
 
 package org.geysermc.geyser.api.block.custom.component;
 
+import org.checkerframework.checker.nullness.qual.NonNull;
+
 import java.util.LinkedHashMap;
 import java.util.Set;
 
-import org.checkerframework.checker.nullness.qual.NonNull;
-
 /**
  * This class is used to store conditions for a placement filter for a custom block.
  * 
@@ -43,7 +43,7 @@ public record PlacementConditions(@NonNull Set<Face> allowedFaces, @NonNull Link
         NORTH,
         SOUTH,
         WEST,
-        EAST;
+        EAST
     }
     
     public enum BlockFilterType {

api/src/main/java/org/geysermc/geyser/api/block/custom/nonvanilla/JavaBlockState.java

@@ -39,7 +39,7 @@ public interface JavaBlockState {
      * 
      * @return whether the block state is waterlogged
      */
-    @NonNull boolean waterlogged();
+    boolean waterlogged();
 
     /**
      * Gets the collision of the block state
@@ -53,7 +53,7 @@ public interface JavaBlockState {
      * 
      * @return whether the block state can be broken with hand
      */
-    @NonNull boolean canBreakWithHand();
+    boolean canBreakWithHand();
 
     /**
      * Gets the pick item of the block state
@@ -74,7 +74,7 @@ public interface JavaBlockState {
      * 
      * @return whether the block state has block entity
      */
-    @Nullable boolean hasBlockEntity();
+    boolean hasBlockEntity();
 
     /**
      * Creates a new {@link JavaBlockState.Builder} instance
@@ -94,17 +94,17 @@ public interface JavaBlockState {
 
         Builder blockHardness(@NonNegative float blockHardness);
 
-        Builder waterlogged(@NonNull boolean waterlogged);
+        Builder waterlogged(boolean waterlogged);
 
         Builder collision(@NonNull JavaBoundingBox[] collision);
 
-        Builder canBreakWithHand(@NonNull boolean canBreakWithHand);
+        Builder canBreakWithHand(boolean canBreakWithHand);
 
         Builder pickItem(@Nullable String pickItem);
 
         Builder pistonBehavior(@Nullable String pistonBehavior);
 
-        Builder hasBlockEntity(@Nullable boolean hasBlockEntity);
+        Builder hasBlockEntity(boolean hasBlockEntity);
 
         JavaBlockState build();
     }

api/src/main/java/org/geysermc/geyser/api/block/custom/nonvanilla/JavaBoundingBox.java

@@ -1,6 +1,4 @@
 package org.geysermc.geyser.api.block.custom.nonvanilla;
 
-import org.checkerframework.checker.nullness.qual.NonNull;
+public record JavaBoundingBox(double middleX, double middleY, double middleZ, double sizeX, double sizeY, double sizeZ) {
-
-public record JavaBoundingBox(@NonNull double middleX, @NonNull double middleY, @NonNull double middleZ, @NonNull double sizeX, @NonNull double sizeY, @NonNull double sizeZ) {
 }

api/src/main/java/org/geysermc/geyser/api/event/EventBus.java

@@ -28,7 +28,6 @@ package org.geysermc.geyser.api.event;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.event.Event;
 import org.geysermc.event.bus.OwnedEventBus;
-import org.geysermc.geyser.api.extension.Extension;
 
 import java.util.Set;
 

api/src/main/java/org/geysermc/geyser/api/event/EventSubscriber.java

@@ -27,7 +27,6 @@ package org.geysermc.geyser.api.event;
 
 import org.geysermc.event.Event;
 import org.geysermc.event.subscribe.OwnedSubscriber;
-import org.geysermc.geyser.api.extension.Extension;
 
 /**
  * Represents a subscribed listener to a {@link Event}. Wraps around

api/src/main/java/org/geysermc/geyser/api/event/connection/GeyserBedrockPingEvent.java

@@ -34,7 +34,7 @@ import java.net.InetSocketAddress;
 
 /**
  * Called whenever Geyser gets pinged
- *
+ * <p>
  * This event allows you to modify/obtain the MOTD, maximum player count, and current number of players online,
  * Geyser will reply to the client with what was given.
  */

api/src/main/java/org/geysermc/geyser/api/event/lifecycle/GeyserDefineCommandsEvent.java

@@ -33,7 +33,7 @@ import java.util.Map;
 
 /**
  * Called when commands are defined within Geyser.
- *
+ * <p>
  * This event allows you to register new commands using the {@link #register(Command)}
  * method and retrieve the default commands defined.
  */

api/src/main/java/org/geysermc/geyser/api/event/lifecycle/GeyserDefineCustomBlocksEvent.java

@@ -28,13 +28,12 @@ package org.geysermc.geyser.api.event.lifecycle;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.api.block.custom.CustomBlockData;
 import org.geysermc.geyser.api.block.custom.CustomBlockState;
-import org.geysermc.geyser.api.block.custom.nonvanilla.JavaBlockItem;
 import org.geysermc.geyser.api.block.custom.nonvanilla.JavaBlockState;
 import org.geysermc.event.Event;
 
 /**
  * Called on Geyser's startup when looking for custom blocks. Custom blocks must be registered through this event.
- *
+ * <p>
  * This event will not be called if the "add-non-bedrock-items" setting is disabled in the Geyser config.
  */
 public abstract class GeyserDefineCustomBlocksEvent implements Event {
@@ -48,8 +47,8 @@ public abstract class GeyserDefineCustomBlocksEvent implements Event {
     /**
      * Registers the given {@link CustomBlockState} as an override for the
      * given java state identifier
-     * Java state identifiers are listed in
+     * Java state identifiers are listed
-     * https://raw.githubusercontent.com/GeyserMC/mappings/master/blocks.json
+     * <a href="https://raw.githubusercontent.com/GeyserMC/mappings/master/blocks.json">here</a>
      *
      * @param javaIdentifier the java state identifier to override
      * @param customBlockState the custom block state with which to override java state identifier

api/src/main/java/org/geysermc/geyser/api/event/lifecycle/GeyserDefineCustomItemsEvent.java

@@ -36,7 +36,7 @@ import java.util.Map;
 
 /**
  * Called on Geyser's startup when looking for custom items. Custom items must be registered through this event.
- *
+ * <p>
  * This event will not be called if the "add non-Bedrock items" setting is disabled in the Geyser config.
  */
 public interface GeyserDefineCustomItemsEvent extends Event {

api/src/main/java/org/geysermc/geyser/api/event/lifecycle/GeyserDefineCustomSkullsEvent.java

@@ -5,7 +5,7 @@ import org.geysermc.event.Event;
 
 /**
  * Called on Geyser's startup when looking for custom skulls. Custom skulls must be registered through this event.
- *
+ * <p>
  * This event will not be called if the "add-non-bedrock-items" setting is disabled in the Geyser config.
  */
 public abstract class GeyserDefineCustomSkullsEvent implements Event {

api/src/main/java/org/geysermc/geyser/api/extension/exception/InvalidDescriptionException.java

@@ -25,10 +25,16 @@
 
 package org.geysermc.geyser.api.extension.exception;
 
+import java.io.Serial;
+
 /**
  * Thrown when an extension's description is invalid.
  */
 public class InvalidDescriptionException extends Exception {
+
+    @Serial
+    private static final long serialVersionUID = 1L;
+
     public InvalidDescriptionException(Throwable cause) {
         super(cause);
     }

api/src/main/java/org/geysermc/geyser/api/extension/exception/InvalidExtensionException.java

@@ -25,10 +25,16 @@
 
 package org.geysermc.geyser.api.extension.exception;
 
+import java.io.Serial;
+
 /**
  * Thrown when an extension is invalid.
  */
 public class InvalidExtensionException extends Exception {
+
+    @Serial
+    private static final long serialVersionUID = 1L;
+
     public InvalidExtensionException(Throwable cause) {
         super(cause);
     }

api/src/main/java/org/geysermc/geyser/api/util/CreativeCategory.java

@@ -51,7 +51,7 @@ public enum CreativeCategory {
      * 
      * @return the name of the category
      */
-    @NonNull public String internalName() {
+    public @NonNull String internalName() {
         return internalName;
     }
 

api/src/main/java/org/geysermc/geyser/api/util/TriState.java

@@ -30,7 +30,7 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * This is a way to represent a boolean, but with a non set value added.
- * This class was inspired by adventure's version https://github.com/KyoriPowered/adventure/blob/main/4/api/src/main/java/net/kyori/adventure/util/TriState.java
+ * This class was inspired by adventure's <a href="https://github.com/KyoriPowered/adventure/blob/main/4/api/src/main/java/net/kyori/adventure/util/TriState.java">TriState</a>
  */
 public enum TriState {
     /**

bootstrap/bungeecord/src/main/java/org/geysermc/geyser/platform/bungeecord/GeyserBungeeDumpInfo.java

@@ -30,6 +30,7 @@ import net.md_5.bungee.api.ProxyServer;
 import net.md_5.bungee.api.plugin.Plugin;
 import org.geysermc.geyser.dump.BootstrapDumpInfo;
 
+import java.net.InetSocketAddress;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -51,7 +52,8 @@ public class GeyserBungeeDumpInfo extends BootstrapDumpInfo {
         this.plugins = new ArrayList<>();
 
         for (net.md_5.bungee.api.config.ListenerInfo listener : proxy.getConfig().getListeners()) {
-            this.listeners.add(new ListenerInfo(listener.getHost().getHostString(), listener.getHost().getPort()));
+            InetSocketAddress address = (InetSocketAddress) listener.getSocketAddress();
+            this.listeners.add(new ListenerInfo(address.getHostString(), address.getPort()));
         }
 
         for (Plugin plugin : proxy.getPluginManager().getPlugins()) {

bootstrap/bungeecord/src/main/java/org/geysermc/geyser/platform/bungeecord/GeyserBungeeInjector.java

@@ -39,6 +39,7 @@ import net.md_5.bungee.api.plugin.Listener;
 import net.md_5.bungee.api.plugin.Plugin;
 import net.md_5.bungee.event.EventHandler;
 import net.md_5.bungee.netty.PipelineUtils;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.network.netty.GeyserInjector;
@@ -125,7 +126,7 @@ public class GeyserBungeeInjector extends GeyserInjector implements Listener {
                 .channel(LocalServerChannelWrapper.class)
                 .childHandler(new ChannelInitializer<>() {
                     @Override
-                    protected void initChannel(Channel ch) throws Exception {
+                    protected void initChannel(@NonNull Channel ch) throws Exception {
                         if (proxy.getConfig().getServers() == null) {
                             // Proxy hasn't finished loading all plugins - it loads the config after all plugins
                             // Probably doesn't need to be translatable?

bootstrap/bungeecord/src/main/java/org/geysermc/geyser/platform/bungeecord/GeyserBungeePingPassthrough.java

@@ -35,6 +35,7 @@ import net.md_5.bungee.api.connection.PendingConnection;
 import net.md_5.bungee.api.event.ProxyPingEvent;
 import net.md_5.bungee.api.plugin.Listener;
 import net.md_5.bungee.protocol.ProtocolConstants;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.ping.GeyserPingInfo;
 import org.geysermc.geyser.ping.IGeyserPingPassthrough;
 
@@ -104,7 +105,7 @@ public class GeyserBungeePingPassthrough implements IGeyserPingPassthrough, List
         }
 
         @Override
-        public InetSocketAddress getVirtualHost() {
+        public @Nullable InetSocketAddress getVirtualHost() {
             return null;
         }
 

bootstrap/bungeecord/src/main/java/org/geysermc/geyser/platform/bungeecord/GeyserBungeePlugin.java

@@ -30,6 +30,7 @@ import net.md_5.bungee.BungeeCord;
 import net.md_5.bungee.api.config.ListenerInfo;
 import net.md_5.bungee.api.plugin.Plugin;
 import net.md_5.bungee.protocol.ProtocolConstants;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.GeyserBootstrap;
@@ -44,7 +45,6 @@ import org.geysermc.geyser.ping.IGeyserPingPassthrough;
 import org.geysermc.geyser.platform.bungeecord.command.GeyserBungeeCommandExecutor;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.FileUtils;
-import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
 import java.io.IOException;
@@ -72,6 +72,7 @@ public class GeyserBungeePlugin extends Plugin implements GeyserBootstrap {
 
     private static boolean INITIALIZED = false;
 
+    @SuppressWarnings({"JavaReflectionMemberAccess", "ResultOfMethodCallIgnored"})
     @Override
     public void onLoad() {
         GeyserLocale.init(this);
@@ -251,7 +252,7 @@ public class GeyserBungeePlugin extends Plugin implements GeyserBootstrap {
         return this.geyserInjector.getServerSocketAddress();
     }
 
-    @NotNull
+    @NonNull
     @Override
     public String getServerBindAddress() {
         return findCompatibleListener().map(InetSocketAddress::getHostString).orElse("");

bootstrap/bungeecord/src/main/java/org/geysermc/geyser/platform/bungeecord/command/BungeeCommandSource.java

@@ -29,6 +29,7 @@ import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.bungeecord.BungeeComponentSerializer;
 import net.md_5.bungee.api.chat.TextComponent;
 import net.md_5.bungee.api.connection.ProxiedPlayer;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.text.GeyserLocale;
 
@@ -50,7 +51,7 @@ public class BungeeCommandSource implements GeyserCommandSource {
     }
 
     @Override
-    public void sendMessage(String message) {
+    public void sendMessage(@NonNull String message) {
         handle.sendMessage(TextComponent.fromLegacyText(message));
     }
 

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/GeyserFabricMod.java

@@ -37,6 +37,8 @@ import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.commands.Commands;
 import net.minecraft.server.MinecraftServer;
 import org.apache.logging.log4j.LogManager;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.GeyserLogger;
@@ -54,8 +56,6 @@ import org.geysermc.geyser.platform.fabric.command.GeyserFabricCommandExecutor;
 import org.geysermc.geyser.platform.fabric.world.GeyserFabricWorldManager;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.FileUtils;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.io.IOException;
@@ -251,7 +251,7 @@ public class GeyserFabricMod implements ModInitializer, GeyserBootstrap {
         return this.server.getServerVersion();
     }
 
-    @NotNull
+    @NonNull
     @Override
     public String getServerBindAddress() {
         String ip = this.server.getLocalIp();

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/command/FabricCommandSender.java

@@ -30,11 +30,12 @@ import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.network.chat.Component;
 import net.minecraft.server.level.ServerPlayer;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.text.ChatColor;
 
-import javax.annotation.Nonnull;
+import java.util.Objects;
 
 public class FabricCommandSender implements GeyserCommandSource {
 
@@ -50,7 +51,7 @@ public class FabricCommandSender implements GeyserCommandSource {
     }
 
     @Override
-    public void sendMessage(@Nonnull String message) {
+    public void sendMessage(@NonNull String message) {
         if (source.getEntity() instanceof ServerPlayer) {
             ((ServerPlayer) source.getEntity()).displayClientMessage(Component.literal(message), false);
         } else {
@@ -62,7 +63,7 @@ public class FabricCommandSender implements GeyserCommandSource {
     public void sendMessage(net.kyori.adventure.text.Component message) {
         if (source.getEntity() instanceof ServerPlayer player) {
             String decoded = GsonComponentSerializer.gson().serialize(message);
-            player.displayClientMessage(Component.Serializer.fromJson(decoded), false);
+            player.displayClientMessage(Objects.requireNonNull(Component.Serializer.fromJson(decoded)), false);
             return;
         }
         GeyserCommandSource.super.sendMessage(message);

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/command/GeyserFabricCommandExecutor.java

@@ -52,12 +52,12 @@ public class GeyserFabricCommandExecutor extends GeyserCommandExecutor implement
     }
 
     @Override
-    public int run(CommandContext context) {
+    public int run(CommandContext<CommandSourceStack> context) {
         return runWithArgs(context, "");
     }
 
-    public int runWithArgs(CommandContext context, String args) {
+    public int runWithArgs(CommandContext<CommandSourceStack> context, String args) {
-        CommandSourceStack source = (CommandSourceStack) context.getSource();
+        CommandSourceStack source = context.getSource();
         FabricCommandSender sender = new FabricCommandSender(source);
         GeyserSession session = getGeyserSession(sender);
         if (!testPermission(source)) {

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/mixin/client/IntegratedServerMixin.java

@@ -42,6 +42,8 @@ import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
+import java.util.Objects;
+
 @Environment(EnvType.CLIENT)
 @Mixin(IntegratedServer.class)
 public class IntegratedServerMixin implements GeyserServerPortGetter {
@@ -58,6 +60,7 @@ public class IntegratedServerMixin implements GeyserServerPortGetter {
             // Ensure player locale has been loaded, in case it's different from Java system language
             GeyserLocale.loadGeyserLocale(this.minecraft.options.languageCode);
             // Give indication that Geyser is loaded
+            Objects.requireNonNull(this.minecraft.player);
             this.minecraft.player.displayClientMessage(Component.literal(GeyserLocale.getPlayerLocaleString("geyser.core.start",
                     this.minecraft.options.languageCode, "localhost", String.valueOf(this.publishedPort))), false);
         }

bootstrap/fabric/src/main/java/org/geysermc/geyser/platform/fabric/world/GeyserFabricWorldManager.java

@@ -39,6 +39,7 @@ import net.minecraft.world.level.block.entity.BannerBlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.LecternBlockEntity;
 import net.minecraft.world.level.chunk.LevelChunk;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3i;
 import org.cloudburstmc.nbt.NbtMap;
 import org.cloudburstmc.nbt.NbtMapBuilder;
@@ -48,9 +49,9 @@ import org.geysermc.geyser.level.GeyserWorldManager;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.BlockEntityUtils;
 
-import javax.annotation.Nonnull;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 
 public class GeyserFabricWorldManager extends GeyserWorldManager {
@@ -73,9 +74,11 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
                 return;
             }
 
+            //noinspection resource - level() is just a getter
             LevelChunk chunk = player.level().getChunk(x, z);
             final int chunkBlockX = x << 4;
             final int chunkBlockZ = z << 4;
+            //noinspection ForLoopReplaceableByForEach - avoid constructing iterator
             for (int i = 0; i < blockEntityInfos.size(); i++) {
                 BlockEntityInfo blockEntityInfo = blockEntityInfos.get(i);
                 BlockEntity blockEntity = chunk.getBlockEntity(new BlockPos(chunkBlockX + blockEntityInfo.getX(),
@@ -92,7 +95,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
             if (player == null) {
                 return;
             }
-
+            //noinspection resource - level() is just a getter
             BlockEntity blockEntity = player.level().getBlockEntity(new BlockPos(x, y, z));
             sendLecternData(session, blockEntity, false);
         });
@@ -159,7 +162,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
         return GameMode.byId(server.getDefaultGameType().getId());
     }
 
-    @Nonnull
+    @NonNull
     @Override
     public CompletableFuture<com.github.steveice10.opennbt.tag.builtin.CompoundTag> getPickItemNbt(GeyserSession session, int x, int y, int z, boolean addNbtData) {
         CompletableFuture<com.github.steveice10.opennbt.tag.builtin.CompoundTag> future = new CompletableFuture<>();
@@ -172,6 +175,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
 
             BlockPos pos = new BlockPos(x, y, z);
             // Don't create a new block entity if invalid
+            //noinspection resource - level() is just a getter
             BlockEntity blockEntity = player.level().getChunkAt(pos).getBlockEntity(pos);
             if (blockEntity instanceof BannerBlockEntity banner) {
                 // Potentially exposes other NBT data? But we need to get the NBT data for the banner patterns *and*
@@ -263,7 +267,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
         }
 
         @Override
-        public void visitCompound(CompoundTag compoundTag) {
+        public void visitCompound(@NonNull CompoundTag compoundTag) {
             currentTag = convert(currentKey, compoundTag);
         }
 
@@ -271,7 +275,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
             OpenNbtTagVisitor visitor = new OpenNbtTagVisitor(name);
             for (String key : compoundTag.getAllKeys()) {
                 visitor.currentKey = key;
-                Tag tag = compoundTag.get(key);
+                Tag tag = Objects.requireNonNull(compoundTag.get(key));
                 tag.accept(visitor);
                 visitor.root.put(visitor.currentTag);
             }
@@ -279,7 +283,7 @@ public class GeyserFabricWorldManager extends GeyserWorldManager {
         }
 
         @Override
-        public void visitEnd(EndTag endTag) {
+        public void visitEnd(@NonNull EndTag endTag) {
         }
     }
 }

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserPaperPingPassthrough.java

@@ -28,11 +28,11 @@ package org.geysermc.geyser.platform.spigot;
 import com.destroystokyo.paper.event.server.PaperServerListPingEvent;
 import com.destroystokyo.paper.network.StatusClient;
 import org.bukkit.Bukkit;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.network.GameProtocol;
 import org.geysermc.geyser.ping.GeyserPingInfo;
 import org.geysermc.geyser.ping.IGeyserPingPassthrough;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import java.lang.reflect.Constructor;
 import java.net.InetSocketAddress;
@@ -50,6 +50,7 @@ public final class GeyserPaperPingPassthrough implements IGeyserPingPassthrough
         this.logger = logger;
     }
 
+    @SuppressWarnings("deprecation")
     @Nullable
     @Override
     public GeyserPingInfo getPingInformation(InetSocketAddress inetSocketAddress) {
@@ -89,7 +90,7 @@ public final class GeyserPaperPingPassthrough implements IGeyserPingPassthrough
 
     private record GeyserStatusClient(InetSocketAddress address) implements StatusClient {
         @Override
-        public @NotNull InetSocketAddress getAddress() {
+        public @NonNull InetSocketAddress getAddress() {
             return address;
         }
 

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotCompressionDisabler.java

@@ -34,7 +34,7 @@ import org.geysermc.geyser.GeyserImpl;
 /**
  * Disables the compression packet (and the compression handlers from being added to the pipeline) for Geyser clients
  * that won't be receiving the data over the network.
- *
+ * <p>
  * As of 1.8 - 1.17.1, compression is enabled in the Netty pipeline by adding a listener after a packet is written.
  * If we simply "cancel" or don't forward the packet, then the listener is never called.
  */

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotDumpInfo.java

@@ -47,6 +47,7 @@ public class GeyserSpigotDumpInfo extends BootstrapDumpInfo {
     private final int serverPort;
     private final List<PluginInfo> plugins;
 
+    @SuppressWarnings("deprecation")
     GeyserSpigotDumpInfo() {
         super();
         this.platformName = Bukkit.getName();

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotInjector.java

@@ -32,6 +32,7 @@ import io.netty.channel.*;
 import io.netty.channel.local.LocalAddress;
 import io.netty.util.concurrent.DefaultThreadFactory;
 import org.bukkit.Bukkit;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.network.netty.GeyserInjector;
 import org.geysermc.geyser.network.netty.LocalServerChannelWrapper;
@@ -74,7 +75,6 @@ public class GeyserSpigotInjector extends GeyserInjector {
         Object connection = null;
         // Find the class that manages network IO
         for (Method m : serverClazz.getDeclaredMethods()) {
-            if (m.getReturnType() != null) {
             // First is Spigot-mapped name, second is Mojang-mapped name which is implemented as future-proofing
             if (m.getReturnType().getSimpleName().equals("ServerConnection") || m.getReturnType().getSimpleName().equals("ServerConnectionListener")) {
                 if (m.getParameterTypes().length == 0) {
@@ -82,7 +82,6 @@ public class GeyserSpigotInjector extends GeyserInjector {
                 }
             }
         }
-        }
         if (connection == null) {
             throw new RuntimeException("Unable to find ServerConnection class!");
         }
@@ -117,7 +116,7 @@ public class GeyserSpigotInjector extends GeyserInjector {
                 .channel(LocalServerChannelWrapper.class)
                 .childHandler(new ChannelInitializer<>() {
                     @Override
-                    protected void initChannel(Channel ch) throws Exception {
+                    protected void initChannel(@NonNull Channel ch) throws Exception {
                         initChannel.invoke(childHandler, ch);
 
                         if (bootstrap.getGeyserConfig().isDisableCompression() && GeyserSpigotCompressionDisabler.ENABLED) {

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotPingPassthrough.java

@@ -30,10 +30,12 @@ import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 import org.bukkit.event.server.ServerListPingEvent;
 import org.bukkit.util.CachedServerIcon;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.geysermc.geyser.network.GameProtocol;
 import org.geysermc.geyser.ping.GeyserPingInfo;
 import org.geysermc.geyser.ping.IGeyserPingPassthrough;
 
-import javax.annotation.Nonnull;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.util.Collections;
@@ -44,8 +46,9 @@ public class GeyserSpigotPingPassthrough implements IGeyserPingPassthrough {
 
     private final GeyserSpigotLogger logger;
 
+    @SuppressWarnings("deprecation")
     @Override
-    public GeyserPingInfo getPingInformation(InetSocketAddress inetSocketAddress) {
+    public @Nullable GeyserPingInfo getPingInformation(InetSocketAddress inetSocketAddress) {
         try {
             ServerListPingEvent event = new GeyserPingEvent(inetSocketAddress.getAddress(), Bukkit.getMotd(), Bukkit.getOnlinePlayers().size(), Bukkit.getMaxPlayers());
             Bukkit.getPluginManager().callEvent(event);
@@ -67,7 +70,7 @@ public class GeyserSpigotPingPassthrough implements IGeyserPingPassthrough {
         public void setServerIcon(CachedServerIcon icon) throws IllegalArgumentException, UnsupportedOperationException {
         }
 
-        @Nonnull
+        @NonNull
         @Override
         public Iterator<Player> iterator() throws UnsupportedOperationException {
             return Collections.emptyIterator();

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotPlugin.java

@@ -42,13 +42,14 @@ import org.bukkit.permissions.Permission;
 import org.bukkit.permissions.PermissionDefault;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.java.JavaPlugin;
-import org.geysermc.geyser.api.util.PlatformType;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.Constants;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.adapters.spigot.SpigotAdapters;
 import org.geysermc.geyser.api.command.Command;
 import org.geysermc.geyser.api.extension.Extension;
+import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.command.GeyserCommandManager;
 import org.geysermc.geyser.configuration.GeyserConfiguration;
 import org.geysermc.geyser.dump.BootstrapDumpInfo;
@@ -66,7 +67,6 @@ import org.geysermc.geyser.platform.spigot.world.manager.GeyserSpigotNativeWorld
 import org.geysermc.geyser.platform.spigot.world.manager.GeyserSpigotWorldManager;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.FileUtils;
-import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
 import java.io.IOException;
@@ -76,6 +76,7 @@ import java.net.SocketAddress;
 import java.nio.file.Path;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.UUID;
 import java.util.logging.Level;
 
@@ -137,6 +138,7 @@ public class GeyserSpigotPlugin extends JavaPlugin implements GeyserBootstrap {
         // This is manually done instead of using Bukkit methods to save the config because otherwise comments get removed
         try {
             if (!getDataFolder().exists()) {
+                //noinspection ResultOfMethodCallIgnored
                 getDataFolder().mkdir();
             }
             File configFile = FileUtils.fileOrCopiedFromResource(new File(getDataFolder(), "config.yml"), "config.yml",
@@ -272,6 +274,7 @@ public class GeyserSpigotPlugin extends JavaPlugin implements GeyserBootstrap {
         }
 
         PluginCommand geyserCommand = this.getCommand("geyser");
+        Objects.requireNonNull(geyserCommand, "base command cannot be null");
         geyserCommand.setExecutor(new GeyserSpigotCommandExecutor(geyser, geyserCommandManager.getCommands()));
 
         for (Map.Entry<Extension, Map<String, Command>> entry : this.geyserCommandManager.extensionCommands().entrySet()) {
@@ -437,7 +440,7 @@ public class GeyserSpigotPlugin extends JavaPlugin implements GeyserBootstrap {
         return false;
     }
 
-    @NotNull
+    @NonNull
     @Override
     public String getServerBindAddress() {
         return Bukkit.getIp();

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/GeyserSpigotVersionChecker.java

@@ -39,6 +39,7 @@ import java.lang.reflect.Modifier;
 public final class GeyserSpigotVersionChecker {
     private static final String VIAVERSION_DOWNLOAD_URL = "https://ci.viaversion.com/job/ViaVersion/";
 
+    @SuppressWarnings("deprecation")
     public static void checkForSupportedProtocol(GeyserLogger logger, boolean viaversion) {
         if (viaversion) {
             checkViaVersionSupportedVersions(logger);

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/PaperAdventure.java

@@ -28,8 +28,8 @@ package org.geysermc.geyser.platform.spigot;
 import com.github.steveice10.mc.protocol.data.DefaultComponentSerializer;
 import net.kyori.adventure.text.Component;
 import org.bukkit.command.CommandSender;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserImpl;
-import org.jetbrains.annotations.Nullable;
 
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
@@ -39,8 +39,8 @@ import java.lang.reflect.Method;
 
 /**
  * Utility class for converting our shaded Adventure into the Adventure bundled in Paper.
- *
+ * <p>
- * Code mostly taken from https://github.com/KyoriPowered/adventure-platform/blob/94d5821f2e755170f42bd8a5fe1d5bf6f66d04ad/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java#L46
+ * Code mostly taken from <a href="https://github.com/KyoriPowered/adventure-platform/blob/94d5821f2e755170f42bd8a5fe1d5bf6f66d04ad/platform-bukkit/src/main/java/net/kyori/adventure/platform/bukkit/PaperFacet.java#L46">here</a>
  * and the MinecraftReflection class.
  */
 public final class PaperAdventure {
@@ -102,7 +102,7 @@ public final class PaperAdventure {
         SEND_MESSAGE_COMPONENT = playerComponentSendMessage;
     }
 
-    public static Object toNativeComponent(final Component component) {
+    public static @Nullable Object toNativeComponent(final Component component) {
         if (NATIVE_GSON_COMPONENT_SERIALIZER_DESERIALIZE_METHOD_BOUND == null) {
             GeyserImpl.getInstance().getLogger().error("Illegal state where Component serialization was called when it wasn't available!");
             return null;

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/ReflectedNames.java

@@ -29,8 +29,8 @@ import com.destroystokyo.paper.event.server.PaperServerListPingEvent;
 import com.destroystokyo.paper.network.StatusClient;
 import org.bukkit.event.server.ServerListPingEvent;
 import org.bukkit.util.CachedServerIcon;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
-import javax.annotation.Nullable;
 import java.lang.reflect.Constructor;
 import java.net.InetAddress;
 
@@ -40,15 +40,8 @@ import java.net.InetAddress;
 public final class ReflectedNames {
 
     static boolean checkPaperPingEvent() {
-        return classExists("com.destroystokyo.paper.event.server.PaperServerListPingEvent");
-    }
-
-    /**
-     * @return if this class name exists
-     */
-    private static boolean classExists(String clazz) {
         try {
-            Class.forName(clazz);
+            Class.forName("com.destroystokyo.paper.event.server.PaperServerListPingEvent");
             return true;
         } catch (ClassNotFoundException e) {
             return false;
@@ -59,7 +52,7 @@ public final class ReflectedNames {
         return getConstructor(ServerListPingEvent.class, InetAddress.class, String.class, boolean.class, int.class, int.class) != null;
     }
 
-    static Constructor<PaperServerListPingEvent> getOldPaperPingConstructor() {
+    static @Nullable Constructor<PaperServerListPingEvent> getOldPaperPingConstructor() {
         if (getConstructor(PaperServerListPingEvent.class, StatusClient.class, String.class, int.class,
                 int.class, String.class, int.class, CachedServerIcon.class) != null) {
             // @NotNull StatusClient client, @NotNull String motd, int numPlayers, int maxPlayers,

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/command/GeyserPaperCommandListener.java

@@ -39,8 +39,8 @@ import java.util.Map;
 
 public final class GeyserPaperCommandListener implements Listener {
 
+    @SuppressWarnings("UnstableApiUsage")
     @EventHandler
-    @SuppressWarnings("deprecation") // Used to indicate an unstable event
     public void onCommandSend(AsyncPlayerSendCommandsEvent<?> event) {
         // Documentation says to check (event.isAsynchronous() || !event.hasFiredAsync()), but as of Paper 1.18.2
         // event.hasFiredAsync is never true

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/command/GeyserSpigotCommandExecutor.java

@@ -29,6 +29,7 @@ import org.bukkit.ChatColor;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
 import org.bukkit.command.TabExecutor;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.command.GeyserCommand;
 import org.geysermc.geyser.command.GeyserCommandExecutor;
@@ -47,7 +48,7 @@ public class GeyserSpigotCommandExecutor extends GeyserCommandExecutor implement
     }
 
     @Override
-    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
+    public boolean onCommand(@NonNull CommandSender sender, @NonNull Command command, @NonNull String label, String[] args) {
         SpigotCommandSource commandSender = new SpigotCommandSource(sender);
         GeyserSession session = getGeyserSession(commandSender);
 
@@ -78,7 +79,7 @@ public class GeyserSpigotCommandExecutor extends GeyserCommandExecutor implement
     }
 
     @Override
-    public List<String> onTabComplete(CommandSender sender, Command command, String label, String[] args) {
+    public List<String> onTabComplete(@NonNull CommandSender sender, @NonNull Command command, @NonNull String label, String[] args) {
         if (args.length == 1) {
             return tabComplete(new SpigotCommandSource(sender));
         }

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/command/SpigotCommandSource.java

@@ -29,6 +29,7 @@ import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.bungeecord.BungeeComponentSerializer;
 import org.bukkit.command.ConsoleCommandSender;
 import org.bukkit.entity.Player;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.platform.spigot.PaperAdventure;
 import org.geysermc.geyser.text.GeyserLocale;
@@ -48,10 +49,11 @@ public class SpigotCommandSource implements GeyserCommandSource {
     }
 
     @Override
-    public void sendMessage(String message) {
+    public void sendMessage(@NonNull String message) {
         handle.sendMessage(message);
     }
 
+    @SuppressWarnings("deprecation")
     @Override
     public void sendMessage(Component message) {
         if (PaperAdventure.canSendMessageUsingComponent()) {
@@ -68,9 +70,11 @@ public class SpigotCommandSource implements GeyserCommandSource {
         return handle instanceof ConsoleCommandSender;
     }
 
+    @SuppressWarnings("deprecation")
     @Override
     public String locale() {
         if (this.handle instanceof Player player) {
+            // getLocale() is deprecated on Paper, but not on Spigot
             return player.getLocale();
         }
 

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/world/manager/GeyserSpigotLegacyNativeWorldManager.java

@@ -37,6 +37,7 @@ import org.geysermc.geyser.platform.spigot.GeyserSpigotPlugin;
 import org.geysermc.geyser.session.GeyserSession;
 
 import java.util.List;
+import java.util.Objects;
 
 /**
  * Used when block IDs need to be translated to the latest version
@@ -52,6 +53,7 @@ public class GeyserSpigotLegacyNativeWorldManager extends GeyserSpigotNativeWorl
         ProtocolVersion serverVersion = plugin.getServerProtocolVersion();
         List<ProtocolPathEntry> protocolList = Via.getManager().getProtocolManager().getProtocolPath(GameProtocol.getJavaProtocolVersion(),
                 serverVersion.getVersion());
+        Objects.requireNonNull(protocolList, "protocolList cannot be null");
         for (int oldBlockId : allBlockStates) {
             int newBlockId = oldBlockId;
             // protocolList should *not* be null; we checked for that before initializing this class

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/world/manager/GeyserSpigotNativeWorldManager.java

@@ -28,11 +28,11 @@ package org.geysermc.geyser.platform.spigot.world.manager;
 import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 import org.bukkit.plugin.Plugin;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.adapters.spigot.SpigotAdapters;
 import org.geysermc.geyser.adapters.spigot.SpigotWorldAdapter;
 import org.geysermc.geyser.level.block.BlockStateValues;
 import org.geysermc.geyser.session.GeyserSession;
-import org.jetbrains.annotations.Nullable;
 
 public class GeyserSpigotNativeWorldManager extends GeyserSpigotWorldManager {
     protected final SpigotWorldAdapter adapter;

bootstrap/spigot/src/main/java/org/geysermc/geyser/platform/spigot/world/manager/GeyserSpigotWorldManager.java

@@ -34,21 +34,23 @@ import org.bukkit.World;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Player;
 import org.bukkit.plugin.Plugin;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.nbt.NbtMap;
 import org.geysermc.erosion.bukkit.BukkitLecterns;
 import org.geysermc.erosion.bukkit.BukkitUtils;
 import org.geysermc.erosion.bukkit.PickBlockUtils;
 import org.geysermc.erosion.bukkit.SchedulerUtils;
+import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.level.GameRule;
 import org.geysermc.geyser.level.WorldManager;
 import org.geysermc.geyser.level.block.BlockStateValues;
 import org.geysermc.geyser.registry.BlockRegistries;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.BlockEntityUtils;
-import org.jetbrains.annotations.Nullable;
 
-import javax.annotation.Nonnull;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 
 /**
@@ -128,7 +130,7 @@ public class GeyserSpigotWorldManager extends WorldManager {
         }
     }
 
-    private Chunk getChunk(World world, int x, int z) {
+    private @Nullable Chunk getChunk(World world, int x, int z) {
         if (!world.isChunkLoaded(x, z)) {
             return null;
         }
@@ -136,6 +138,7 @@ public class GeyserSpigotWorldManager extends WorldManager {
     }
 
     private void sendLecternData(GeyserSession session, Chunk chunk, List<BlockEntityInfo> blockEntityInfos) {
+        //noinspection ForLoopReplaceableByForEach - avoid constructing Iterator
         for (int i = 0; i < blockEntityInfos.size(); i++) {
             BlockEntityInfo info = blockEntityInfos.get(i);
             Block block = chunk.getBlock(info.getX(), info.getY(), info.getZ());
@@ -156,19 +159,34 @@ public class GeyserSpigotWorldManager extends WorldManager {
     }
 
     public boolean getGameRuleBool(GeyserSession session, GameRule gameRule) {
-        String value = Bukkit.getPlayer(session.getPlayerEntity().getUsername()).getWorld().getGameRuleValue(gameRule.getJavaID());
+        org.bukkit.GameRule<?> bukkitGameRule = org.bukkit.GameRule.getByName(gameRule.getJavaID());
-        if (!value.isEmpty()) {
+        if (bukkitGameRule == null) {
-            return Boolean.parseBoolean(value);
+            GeyserImpl.getInstance().getLogger().debug("Unknown game rule " + gameRule.getJavaID());
+            return gameRule.getDefaultBooleanValue();
         }
+
+        Player bukkitPlayer = Objects.requireNonNull(Bukkit.getPlayer(session.getPlayerEntity().getUuid()));
+        Object value = bukkitPlayer.getWorld().getGameRuleValue(bukkitGameRule);
+        if (value instanceof Boolean booleanValue) {
+            return booleanValue;
+        }
+        GeyserImpl.getInstance().getLogger().debug("Expected a bool for " + gameRule + " but got " + value);
         return gameRule.getDefaultBooleanValue();
     }
 
     @Override
     public int getGameRuleInt(GeyserSession session, GameRule gameRule) {
-        String value = Bukkit.getPlayer(session.getPlayerEntity().getUsername()).getWorld().getGameRuleValue(gameRule.getJavaID());
+        org.bukkit.GameRule<?> bukkitGameRule = org.bukkit.GameRule.getByName(gameRule.getJavaID());
-        if (!value.isEmpty()) {
+        if (bukkitGameRule == null) {
-            return Integer.parseInt(value);
+            GeyserImpl.getInstance().getLogger().debug("Unknown game rule " + gameRule.getJavaID());
+            return gameRule.getDefaultIntValue();
         }
+        Player bukkitPlayer = Objects.requireNonNull(Bukkit.getPlayer(session.getPlayerEntity().getUuid()));
+        Object value = bukkitPlayer.getWorld().getGameRuleValue(bukkitGameRule);
+        if (value instanceof Integer intValue) {
+            return intValue;
+        }
+        GeyserImpl.getInstance().getLogger().debug("Expected an int for " + gameRule + " but got " + value);
         return gameRule.getDefaultIntValue();
     }
 
@@ -179,12 +197,11 @@ public class GeyserSpigotWorldManager extends WorldManager {
 
     @Override
     public boolean hasPermission(GeyserSession session, String permission) {
-        return Bukkit.getPlayer(session.getPlayerEntity().getUsername()).hasPermission(permission);
+        return Objects.requireNonNull(Bukkit.getPlayer(session.getPlayerEntity().getUsername())).hasPermission(permission);
     }
 
-    @Nonnull
     @Override
-    public CompletableFuture<@Nullable CompoundTag> getPickItemNbt(GeyserSession session, int x, int y, int z, boolean addNbtData) {
+    public @NonNull CompletableFuture<@Nullable CompoundTag> getPickItemNbt(GeyserSession session, int x, int y, int z, boolean addNbtData) {
         CompletableFuture<@Nullable CompoundTag> future = new CompletableFuture<>();
         Player bukkitPlayer;
         if ((bukkitPlayer = Bukkit.getPlayer(session.getPlayerEntity().getUuid())) == null) {

bootstrap/standalone/src/main/java/org/geysermc/geyser/platform/standalone/GeyserStandaloneBootstrap.java

@@ -38,6 +38,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.core.Appender;
 import org.apache.logging.log4j.core.Logger;
 import org.apache.logging.log4j.core.appender.ConsoleAppender;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.GeyserImpl;
@@ -51,7 +52,6 @@ import org.geysermc.geyser.platform.standalone.gui.GeyserStandaloneGUI;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.FileUtils;
 import org.geysermc.geyser.util.LoopbackUtil;
-import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
 import java.io.IOException;
@@ -292,7 +292,7 @@ public class GeyserStandaloneBootstrap implements GeyserBootstrap {
         return new GeyserStandaloneDumpInfo(this);
     }
 
-    @NotNull
+    @NonNull
     @Override
     public String getServerBindAddress() {
         throw new IllegalStateException();
@@ -325,7 +325,7 @@ public class GeyserStandaloneBootstrap implements GeyserBootstrap {
 
         // Get the ignored properties
         Set<String> ignoredProperties = OBJECT_MAPPER.getSerializationConfig().getAnnotationIntrospector()
-                .findPropertyIgnorals(beanDescription.getClassInfo()).getIgnored();
+                .findPropertyIgnoralByName(OBJECT_MAPPER.getSerializationConfig() ,beanDescription.getClassInfo()).getIgnored();
 
         // Filter properties removing the ignored ones
         return properties.stream()
@@ -340,7 +340,7 @@ public class GeyserStandaloneBootstrap implements GeyserBootstrap {
      * @param parentObject The object to alter
      * @param value The new value of the property
      */
-    @SuppressWarnings("unchecked") // Required for enum usage
+    @SuppressWarnings({"unchecked", "rawtypes"}) // Required for enum usage
     private static void setConfigOption(BeanPropertyDefinition property, Object parentObject, Object value) {
         Object parsedValue = value;
 

bootstrap/standalone/src/main/java/org/geysermc/geyser/platform/standalone/gui/ColorPane.java

@@ -28,11 +28,16 @@ package org.geysermc.geyser.platform.standalone.gui;
 import javax.swing.*;
 import javax.swing.text.*;
 import java.awt.*;
+import java.io.Serial;
 
 /**
- * This class was based on this code: https://stackoverflow.com/a/6899478/5299903
+ * This class was based on this <a href="https://stackoverflow.com/a/6899478/5299903">code</a>
  */
 public class ColorPane extends JTextPane {
+
+    @Serial
+    private static final long serialVersionUID = 1L;
+
     private static Color colorCurrent = ANSIColor.RESET.getColor();
     private String remaining = "";
 
@@ -62,7 +67,7 @@ public class ColorPane extends JTextPane {
         int aPos = 0;   // current char position in addString
         int aIndex; // index of next Escape sequence
         int mIndex; // index of "m" terminating Escape sequence
-        String tmpString = "";
+        String tmpString;
         boolean stillSearching = true; // true until no more Escape sequences
         String addString = remaining + s;
         remaining = "";

bootstrap/standalone/src/main/java/org/geysermc/geyser/platform/standalone/gui/GeyserStandaloneGUI.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.platform.standalone.gui;
 
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.GeyserLogger;
 import org.geysermc.geyser.command.GeyserCommandManager;
@@ -64,7 +65,6 @@ public class GeyserStandaloneGUI {
     private final List<Integer> ramValues = new ArrayList<>();
 
     private final DefaultTableModel playerTableModel = new DefaultTableModel();
-    private final JTable playerTable = new JTable(playerTableModel);
 
     /**
      * Create and show the Geyser-Standalone GUI
@@ -158,6 +158,7 @@ public class GeyserStandaloneGUI {
         playerTableModel.addColumn(GeyserLocale.getLocaleStringLog("geyser.gui.table.ip"));
         playerTableModel.addColumn(GeyserLocale.getLocaleStringLog("geyser.gui.table.username"));
 
+        JTable playerTable = new JTable(playerTableModel);
         JScrollPane playerScrollPane = new JScrollPane(playerTable);
         rightContentPane.add(playerScrollPane);
 
@@ -253,12 +254,12 @@ public class GeyserStandaloneGUI {
             }
 
             @Override
-            public void write(byte[] b, int off, int len) {
+            public void write(byte @NonNull [] b, int off, int len) {
                 appendConsole(new String(b, off, len));
             }
 
             @Override
-            public void write(byte[] b) {
+            public void write(byte @NonNull[] b) {
                 write(b, 0, b.length);
             }
         };

bootstrap/standalone/src/main/java/org/geysermc/geyser/platform/standalone/gui/GraphPanel.java

@@ -29,15 +29,20 @@ import lombok.Setter;
 
 import javax.swing.*;
 import java.awt.*;
+import java.io.Serial;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 
 /**
  * This has been modified to fit Geyser more but is based on
- * https://gist.github.com/roooodcastro/6325153#gistcomment-3107524
+ * <a href="https://gist.github.com/roooodcastro/6325153#gistcomment-3107524">this Github gist</a>
  */
 public final class GraphPanel extends JPanel {
+
+    @Serial
+    private static final long serialVersionUID = 1L;
+
     private final static int padding = 10;
     private final static int labelPadding = 25;
     private final static int pointWidth = 4;
@@ -103,7 +108,7 @@ public final class GraphPanel extends JPanel {
                 g.drawLine(padding + labelPadding + 1 + pointWidth, y, width - padding, y);
 
                 g.setColor(Color.BLACK);
-                final int tickValue = (int) (minScore + ((scoreRange * i) / numberYDivisions));
+                final int tickValue = minScore + ((scoreRange * i) / numberYDivisions);
                 final String yLabel = tickValue + "";
                 final int labelWidth = fontMetrics.stringWidth(yLabel);
                 g.drawString(yLabel, x1 - labelWidth - 5, y + (fontHeight / 2) - 3);

bootstrap/velocity/src/main/java/org/geysermc/geyser/platform/velocity/GeyserVelocityInjector.java

@@ -29,6 +29,7 @@ import com.velocitypowered.api.proxy.ProxyServer;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.*;
 import io.netty.channel.local.LocalAddress;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.network.netty.GeyserInjector;
 import org.geysermc.geyser.network.netty.LocalServerChannelWrapper;
@@ -76,7 +77,7 @@ public class GeyserVelocityInjector extends GeyserInjector {
                 .channel(LocalServerChannelWrapper.class)
                 .childHandler(new ChannelInitializer<>() {
                     @Override
-                    protected void initChannel(Channel ch) throws Exception {
+                    protected void initChannel(@NonNull Channel ch) throws Exception {
                         initChannel.invoke(channelInitializer, ch);
 
                         if (bootstrap.getGeyserConfig().isDisableCompression() && GeyserVelocityCompressionDisabler.ENABLED) {

bootstrap/velocity/src/main/java/org/geysermc/geyser/platform/velocity/GeyserVelocityPlugin.java

@@ -36,11 +36,13 @@ import com.velocitypowered.api.plugin.Plugin;
 import com.velocitypowered.api.proxy.ProxyServer;
 import lombok.Getter;
 import net.kyori.adventure.util.Codec;
-import org.geysermc.geyser.api.util.PlatformType;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserBootstrap;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.command.Command;
 import org.geysermc.geyser.api.extension.Extension;
+import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.command.GeyserCommandManager;
 import org.geysermc.geyser.configuration.GeyserConfiguration;
 import org.geysermc.geyser.dump.BootstrapDumpInfo;
@@ -49,8 +51,6 @@ import org.geysermc.geyser.ping.IGeyserPingPassthrough;
 import org.geysermc.geyser.platform.velocity.command.GeyserVelocityCommandExecutor;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.FileUtils;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
 
 import java.io.File;
@@ -222,7 +222,7 @@ public class GeyserVelocityPlugin implements GeyserBootstrap {
         return this.geyserInjector.getServerSocketAddress();
     }
 
-    @NotNull
+    @NonNull
     @Override
     public String getServerBindAddress() {
         return proxyServer.getBoundAddress().getHostString();

bootstrap/velocity/src/main/java/org/geysermc/geyser/platform/velocity/command/VelocityCommandSource.java

@@ -30,6 +30,7 @@ import com.velocitypowered.api.proxy.ConsoleCommandSource;
 import com.velocitypowered.api.proxy.Player;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.text.GeyserLocale;
 
@@ -56,7 +57,7 @@ public class VelocityCommandSource implements GeyserCommandSource {
     }
 
     @Override
-    public void sendMessage(String message) {
+    public void sendMessage(@NonNull String message) {
         handle.sendMessage(LegacyComponentSerializer.legacy('§').deserialize(message));
     }
 

common/src/main/java/org/geysermc/floodgate/crypto/AesKeyProducer.java

@@ -32,7 +32,7 @@ import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
 
 public final class AesKeyProducer implements KeyProducer {
-    public static int KEY_SIZE = 128;
+    public static final int KEY_SIZE = 128;
 
     @Override
     public SecretKey produce() {

common/src/main/java/org/geysermc/floodgate/crypto/FloodgateCipher.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.floodgate.crypto;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.floodgate.util.InvalidFormatException;
 
 import java.security.Key;
@@ -97,7 +98,8 @@ public interface FloodgateCipher {
      * @return the decrypted data in a UTF-8 String
      * @throws Exception when the decrypting failed
      */
-    default String decryptToString(byte[] data) throws Exception {
+    @SuppressWarnings("unused")
+    default @Nullable String decryptToString(byte[] data) throws Exception {
         byte[] decrypted = decrypt(data);
         if (decrypted == null) {
             return null;
@@ -113,6 +115,7 @@ public interface FloodgateCipher {
      * @return the decrypted data in a byte[]
      * @throws Exception when the decrypting failed
      */
+    @SuppressWarnings("unused")
     default byte[] decryptFromString(String data) throws Exception {
         return decrypt(data.getBytes(UTF_8));
     }

common/src/main/java/org/geysermc/floodgate/crypto/KeyProducer.java

@@ -31,7 +31,7 @@ import java.nio.file.Path;
 import java.security.Key;
 
 public interface KeyProducer {
-    Key produce();
+    @SuppressWarnings("unused") Key produce();
     Key produceFrom(byte[] keyFileData);
 
     default Key produceFrom(Path keyFileLocation) throws IOException {

common/src/main/java/org/geysermc/floodgate/news/NewsItem.java

@@ -109,6 +109,7 @@ public final class NewsItem {
         return (T) data;
     }
 
+    @SuppressWarnings("unused")
     public String getRawMessage() {
         return message;
     }

common/src/main/java/org/geysermc/floodgate/news/NewsItemAction.java

@@ -25,6 +25,8 @@
 
 package org.geysermc.floodgate.news;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
+
 public enum NewsItemAction {
     ON_SERVER_STARTED,
     ON_OPERATOR_JOIN,
@@ -33,7 +35,7 @@ public enum NewsItemAction {
 
     private static final NewsItemAction[] VALUES = values();
 
-    public static NewsItemAction getByName(String actionName) {
+    public static @Nullable NewsItemAction getByName(String actionName) {
         for (NewsItemAction type : VALUES) {
             if (type.name().equalsIgnoreCase(actionName)) {
                 return type;

common/src/main/java/org/geysermc/floodgate/news/NewsItemMessage.java

@@ -26,6 +26,7 @@
 package org.geysermc.floodgate.news;
 
 import com.google.gson.JsonArray;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 // {} is used for things that have to be filled in by the server,
 // {@} is for things that have to be filled in by us
@@ -49,7 +50,7 @@ public enum NewsItemMessage {
         this.messageSplitted = messageFormat.split(" ");
     }
 
-    public static NewsItemMessage getById(int id) {
+    public static @Nullable NewsItemMessage getById(int id) {
         return VALUES.length > id ? VALUES[id] : null;
     }
 

common/src/main/java/org/geysermc/floodgate/news/NewsType.java

@@ -26,6 +26,7 @@
 package org.geysermc.floodgate.news;
 
 import com.google.gson.JsonObject;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.floodgate.news.data.*;
 
 import java.util.function.Function;
@@ -44,7 +45,7 @@ public enum NewsType {
         this.readFunction = readFunction;
     }
 
-    public static NewsType getByName(String newsType) {
+    public static @Nullable NewsType getByName(String newsType) {
         for (NewsType type : VALUES) {
             if (type.name().equalsIgnoreCase(newsType)) {
                 return type;

common/src/main/java/org/geysermc/floodgate/news/data/BuildSpecificData.java

@@ -56,6 +56,7 @@ public final class BuildSpecificData implements ItemData {
                 (allAffected || buildId > affectedGreaterThan && buildId < affectedLessThan);
     }
 
+    @SuppressWarnings("unused")
     public String getBranch() {
         return branch;
     }

common/src/main/java/org/geysermc/floodgate/news/data/ConfigSpecificData.java

@@ -51,6 +51,7 @@ public final class ConfigSpecificData implements ItemData {
         return configSpecificData;
     }
 
+    @SuppressWarnings("unused")
     public boolean isAffected(Map<String, String> config) {
         for (Map.Entry<String, Pattern> entry : affectedKeys.entrySet()) {
             if (config.containsKey(entry.getKey())) {

common/src/main/java/org/geysermc/floodgate/util/BedrockData.java

@@ -72,6 +72,7 @@ public final class BedrockData implements Cloneable {
                 false, subscribeId, verifyCode);
     }
 
+    @SuppressWarnings("unused")
     public static BedrockData fromString(String data) {
         String[] split = data.split("\0");
         if (split.length != EXPECTED_LENGTH) {
@@ -92,6 +93,7 @@ public final class BedrockData implements Cloneable {
                 dataLength);
     }
 
+    @SuppressWarnings("unused")
     public boolean hasPlayerLink() {
         return linkedPlayer != null;
     }

common/src/main/java/org/geysermc/floodgate/util/InvalidFormatException.java

@@ -26,6 +26,9 @@
 package org.geysermc.floodgate.util;
 
 public class InvalidFormatException extends Exception {
+
+    private static final long serialVersionUID = 1L;
+
     public InvalidFormatException(String message) {
         super(message);
     }

common/src/main/java/org/geysermc/floodgate/util/LinkedPlayer.java

@@ -28,6 +28,7 @@ package org.geysermc.floodgate.util;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.UUID;
 
@@ -56,7 +57,7 @@ public final class LinkedPlayer implements Cloneable {
         return new LinkedPlayer(javaUsername, javaUniqueId, bedrockId);
     }
 
-    public static LinkedPlayer fromString(String data) {
+    public static @Nullable LinkedPlayer fromString(String data) {
         String[] split = data.split(";");
         if (split.length != 3) {
             return null;

common/src/main/java/org/geysermc/floodgate/util/UiProfile.java

@@ -25,6 +25,8 @@
 
 package org.geysermc.floodgate.util;
 
+import org.checkerframework.checker.nullness.qual.NonNull;
+
 public enum UiProfile {
     CLASSIC,
     POCKET;
@@ -37,7 +39,7 @@ public enum UiProfile {
      * @param id the UiProfile identifier
      * @return The UiProfile or {@link #CLASSIC} if the UiProfile wasn't found
      */
-    public static UiProfile fromId(int id) {
+    public static @NonNull UiProfile fromId(int id) {
         return VALUES.length > id ? VALUES[id] : VALUES[0];
     }
 }

common/src/main/java/org/geysermc/floodgate/util/WebsocketEventType.java

@@ -25,6 +25,8 @@
 
 package org.geysermc.floodgate.util;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
+
 public enum WebsocketEventType {
     /**
      * Sent once we successfully connected to the server
@@ -81,7 +83,7 @@ public enum WebsocketEventType {
         this.id = id;
     }
 
-    public static WebsocketEventType fromId(int id) {
+    public static @Nullable WebsocketEventType fromId(int id) {
         return VALUES.length > id ? VALUES[id] : null;
     }
 

core/src/main/java/org/geysermc/geyser/GeyserBootstrap.java

@@ -152,7 +152,7 @@ public interface GeyserBootstrap {
      * @param resource Resource to get
      * @return InputStream of the given resource
      */
-    default @NonNull InputStream getResource(String resource) {
+    default @NonNull InputStream getResourceOrThrow(@NonNull String resource) {
         InputStream stream = getResourceOrNull(resource);
         if (stream == null) {
             throw new AssertionError("Unable to find resource: " + resource);

core/src/main/java/org/geysermc/geyser/GeyserImpl.java

@@ -71,6 +71,7 @@ import org.geysermc.geyser.level.WorldManager;
 import org.geysermc.geyser.network.netty.GeyserServer;
 import org.geysermc.geyser.registry.BlockRegistries;
 import org.geysermc.geyser.registry.Registries;
+import org.geysermc.geyser.registry.provider.ProviderSupplier;
 import org.geysermc.geyser.scoreboard.ScoreboardUpdater;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.session.PendingMicrosoftAuthentication;
@@ -622,7 +623,7 @@ public class GeyserImpl implements GeyserApi {
      */
     public boolean isProductionEnvironment() {
         // First is if Blossom runs, second is if Blossom doesn't run
-        // noinspection ConstantConditions - changes in production
+        //noinspection ConstantConditions,MismatchedStringCase - changes in production
         return !("git-local/dev-0000000".equals(GeyserImpl.GIT_VERSION) || "${gitVersion}".equals(GeyserImpl.GIT_VERSION));
     }
 
@@ -638,8 +639,13 @@ public class GeyserImpl implements GeyserApi {
     }
 
     @Override
+    @SuppressWarnings("unchecked")
     public <R extends T, T> @NonNull R provider(@NonNull Class<T> apiClass, @Nullable Object... args) {
-        return (R) Registries.PROVIDERS.get(apiClass).create(args);
+        ProviderSupplier provider = Registries.PROVIDERS.get(apiClass);
+        if (provider == null) {
+            throw new IllegalArgumentException("No provider found for " + apiClass);
+        }
+        return (R) provider.create(args);
     }
 
     @Override

core/src/main/java/org/geysermc/geyser/GeyserLogger.java

@@ -26,9 +26,10 @@
 package org.geysermc.geyser;
 
 import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.command.GeyserCommandSource;
 
-import javax.annotation.Nullable;
 
 public interface GeyserLogger extends GeyserCommandSource {
 
@@ -119,7 +120,7 @@ public interface GeyserLogger extends GeyserCommandSource {
     }
 
     @Override
-    default void sendMessage(String message) {
+    default void sendMessage(@NonNull String message) {
         info(message);
     }
 

core/src/main/java/org/geysermc/geyser/GeyserMain.java

@@ -30,6 +30,7 @@ import java.io.InputStream;
 import java.lang.reflect.Method;
 import java.nio.charset.StandardCharsets;
 import java.util.Locale;
+import java.util.Objects;
 import java.util.Scanner;
 
 public class GeyserMain {
@@ -61,8 +62,8 @@ public class GeyserMain {
             helpStream = GeyserMain.class.getClassLoader().getResourceAsStream("languages/run-help/en_US.txt");
         }
 
-        Scanner help = new Scanner(helpStream, StandardCharsets.UTF_8).useDelimiter("\\Z");
+        Scanner help = new Scanner(Objects.requireNonNull(helpStream), StandardCharsets.UTF_8).useDelimiter("\\Z");
-        String line = "";
+        String line;
         while (help.hasNext()) {
             line = help.next();
 

core/src/main/java/org/geysermc/geyser/command/GeyserCommand.java

@@ -29,10 +29,10 @@ import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import lombok.experimental.Accessors;
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.api.command.Command;
 import org.geysermc.geyser.session.GeyserSession;
 
-import javax.annotation.Nullable;
 import java.util.Collections;
 import java.util.List;
 
@@ -73,15 +73,6 @@ public abstract class GeyserCommand implements Command {
         return Collections.emptyList();
     }
 
-    /**
-     * Shortcut to {@link #subCommands()} ()}{@code .isEmpty()}.
-     *
-     * @return true if there are subcommand present for this command.
-     */
-    public boolean hasSubCommands() {
-        return !this.subCommands().isEmpty();
-    }
-
     public void setAliases(List<String> aliases) {
         this.aliases = aliases;
     }

core/src/main/java/org/geysermc/geyser/command/GeyserCommandExecutor.java

@@ -26,11 +26,11 @@
 package org.geysermc.geyser.command;
 
 import lombok.AllArgsConstructor;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.command.Command;
 import org.geysermc.geyser.session.GeyserSession;
 
-import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;

core/src/main/java/org/geysermc/geyser/command/GeyserCommandManager.java

@@ -29,6 +29,7 @@ import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.command.Command;
@@ -53,8 +54,6 @@ import org.geysermc.geyser.event.type.GeyserDefineCommandsEventImpl;
 import org.geysermc.geyser.extension.command.GeyserExtensionCommand;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.text.GeyserLocale;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.Collections;
 import java.util.HashMap;
@@ -136,12 +135,12 @@ public class GeyserCommandManager {
         }
     }
 
-    @NotNull
+    @NonNull
     public Map<String, Command> commands() {
         return Collections.unmodifiableMap(this.commands);
     }
 
-    @NotNull
+    @NonNull
     public Map<Extension, Map<String, Command>> extensionCommands() {
         return Collections.unmodifiableMap(this.extensionCommands);
     }

core/src/main/java/org/geysermc/geyser/command/defaults/ConnectionTestCommand.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.command.defaults;
 
 import com.fasterxml.jackson.databind.JsonNode;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.command.GeyserCommand;
@@ -34,7 +35,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.LoopbackUtil;
 import org.geysermc.geyser.util.WebUtils;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.Random;
 import java.util.concurrent.CompletableFuture;

core/src/main/java/org/geysermc/geyser/command/defaults/DumpCommand.java

@@ -98,7 +98,7 @@ public class DumpCommand extends GeyserCommand {
             return;
         }
 
-        String uploadedDumpUrl = "";
+        String uploadedDumpUrl;
 
         if (offlineDump) {
             sender.sendMessage(GeyserLocale.getPlayerLocaleString("geyser.commands.dump.writing", sender.locale()));

core/src/main/java/org/geysermc/geyser/command/defaults/ExtensionsCommand.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.command.defaults;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.extension.Extension;
 import org.geysermc.geyser.command.GeyserCommand;
@@ -32,7 +33,6 @@ import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.text.ChatColor;
 import org.geysermc.geyser.text.GeyserLocale;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.Comparator;
 import java.util.List;

core/src/main/java/org/geysermc/geyser/command/defaults/VersionCommand.java

@@ -27,8 +27,8 @@ package org.geysermc.geyser.command.defaults;
 
 import org.cloudburstmc.protocol.bedrock.codec.BedrockCodec;
 import org.geysermc.geyser.Constants;
-import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.GeyserImpl;
+import org.geysermc.geyser.api.util.PlatformType;
 import org.geysermc.geyser.command.GeyserCommand;
 import org.geysermc.geyser.command.GeyserCommandSource;
 import org.geysermc.geyser.network.GameProtocol;
@@ -37,7 +37,6 @@ import org.geysermc.geyser.text.ChatColor;
 import org.geysermc.geyser.text.GeyserLocale;
 import org.geysermc.geyser.util.WebUtils;
 
-import java.io.IOException;
 import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
@@ -77,7 +76,7 @@ public class VersionCommand extends GeyserCommand {
             sender.sendMessage(GeyserLocale.getPlayerLocaleString("geyser.commands.version.checking", sender.locale()));
             try {
                 String buildXML = WebUtils.getBody("https://ci.opencollab.dev/job/GeyserMC/job/Geyser/job/" +
-                        URLEncoder.encode(GeyserImpl.BRANCH, StandardCharsets.UTF_8.toString()) + "/lastSuccessfulBuild/api/xml?xpath=//buildNumber");
+                        URLEncoder.encode(GeyserImpl.BRANCH, StandardCharsets.UTF_8) + "/lastSuccessfulBuild/api/xml?xpath=//buildNumber");
                 if (buildXML.startsWith("<buildNumber>")) {
                     int latestBuildNum = Integer.parseInt(buildXML.replaceAll("<(\\\\)?(/)?buildNumber>", "").trim());
                     int buildNum = this.geyser.buildNumber();
@@ -90,7 +89,7 @@ public class VersionCommand extends GeyserCommand {
                 } else {
                     throw new AssertionError("buildNumber missing");
                 }
-            } catch (IOException e) {
+            } catch (Exception e) {
                 GeyserImpl.getInstance().getLogger().error(GeyserLocale.getLocaleStringLog("geyser.commands.version.failed"), e);
                 sender.sendMessage(ChatColor.RED + GeyserLocale.getPlayerLocaleString("geyser.commands.version.failed", sender.locale()));
             }

core/src/main/java/org/geysermc/geyser/configuration/GeyserConfiguration.java

@@ -52,6 +52,7 @@ public interface GeyserConfiguration {
 
     List<String> getSavedUserLogins();
 
+    @SuppressWarnings("BooleanMethodIsAlwaysInverted")
     boolean isCommandSuggestions();
 
     @JsonIgnore
@@ -93,6 +94,7 @@ public interface GeyserConfiguration {
 
     boolean isForceResourcePacks();
 
+    @SuppressWarnings("BooleanMethodIsAlwaysInverted")
     boolean isXboxAchievementsEnabled();
 
     int getCacheImages();

core/src/main/java/org/geysermc/geyser/configuration/GeyserJacksonConfiguration.java

@@ -34,6 +34,7 @@ import com.fasterxml.jackson.databind.JsonDeserializer;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import lombok.Getter;
 import lombok.Setter;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.api.network.AuthType;
 import org.geysermc.geyser.network.CIDRMatcher;
@@ -158,7 +159,7 @@ public abstract class GeyserJacksonConfiguration implements GeyserConfiguration
         private String address = "0.0.0.0";
 
         @Override
-        public String address() {
+        public @NonNull String address() {
             return address;
         }
 
@@ -260,7 +261,7 @@ public abstract class GeyserJacksonConfiguration implements GeyserConfiguration
         private AuthType authType = AuthType.ONLINE;
 
         @Override
-        public AuthType authType() {
+        public @NonNull AuthType authType() {
             return authType;
         }
 

core/src/main/java/org/geysermc/geyser/dump/DumpInfo.java

@@ -33,7 +33,6 @@ import com.google.common.io.ByteSource;
 import com.google.common.io.Files;
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
-import lombok.AllArgsConstructor;
 import lombok.Getter;
 import org.cloudburstmc.protocol.bedrock.codec.BedrockCodec;
 import org.geysermc.floodgate.util.DeviceOs;
@@ -106,8 +105,8 @@ public class DumpInfo {
             // https://stackoverflow.com/questions/304268/getting-a-files-md5-checksum-in-java
             File file = new File(DumpInfo.class.getProtectionDomain().getCodeSource().getLocation().toURI());
             ByteSource byteSource = Files.asByteSource(file);
-            // Jenkins uses MD5 for its hash
+            // Jenkins uses MD5 for its hash - TODO remove
-            //noinspection UnstableApiUsage
+            //noinspection UnstableApiUsage,deprecation
             md5Hash = byteSource.hash(Hashing.md5()).toString();
             //noinspection UnstableApiUsage
             sha256Hash = byteSource.hash(Hashing.sha256()).toString();
@@ -118,7 +117,7 @@ public class DumpInfo {
         }
         this.hashInfo = new HashInfo(md5Hash, sha256Hash);
 
-        this.ramInfo = new DumpInfo.RamInfo();
+        this.ramInfo = new RamInfo();
 
         if (addLog) {
             this.logsInfo = new LogsInfo();
@@ -202,7 +201,7 @@ public class DumpInfo {
         private boolean checkDockerBasic() {
             try {
                 String OS = System.getProperty("os.name").toLowerCase();
-                if (OS.indexOf("nix") >= 0 || OS.indexOf("nux") >= 0 || OS.indexOf("aix") > 0) {
+                if (OS.contains("nix") || OS.contains("nux") || OS.indexOf("aix") > 0) {
                     String output = new String(java.nio.file.Files.readAllBytes(Paths.get("/proc/1/cgroup")));
 
                     if (output.contains("docker")) {
@@ -259,60 +258,30 @@ public class DumpInfo {
         }
     }
 
-    @AllArgsConstructor
+    public record HashInfo(String md5Hash, String sha256Hash) {
-    @Getter
-    public static class HashInfo {
-        private final String md5Hash;
-        private final String sha256Hash;
     }
 
-    @Getter
+    public record RamInfo(long free, long total, long max) {
-    public static class RamInfo {
+        public RamInfo() {
-        private final long free;
+            this(Runtime.getRuntime().freeMemory() / MEGABYTE,
-        private final long total;
+                    Runtime.getRuntime().totalMemory() / MEGABYTE,
-        private final long max;
+                    Runtime.getRuntime().maxMemory() / MEGABYTE);
-
-        RamInfo() {
-            this.free = Runtime.getRuntime().freeMemory() / MEGABYTE;
-            this.total = Runtime.getRuntime().totalMemory() / MEGABYTE;
-            this.max = Runtime.getRuntime().maxMemory() / MEGABYTE;
         }
     }
 
     /**
      * E.G. `-Xmx1024M` - all runtime JVM flags on this machine
      */
-    @Getter
+    public record FlagsInfo(List<String> flags) {
-    public static class FlagsInfo {
+        public FlagsInfo() {
-        private final List<String> flags;
+            this(ManagementFactory.getRuntimeMXBean().getInputArguments());
-
-        FlagsInfo() {
-            this.flags = ManagementFactory.getRuntimeMXBean().getInputArguments();
         }
     }
 
-    @Getter
+    public record ExtensionInfo(boolean enabled, String name, String version, String apiVersion, String main, List<String> authors) {
-    @AllArgsConstructor
-    public static class ExtensionInfo {
-        public boolean enabled;
-        public String name;
-        public String version;
-        public String apiVersion;
-        public String main;
-        public List<String> authors;
     }
 
-    @Getter
+    public record GitInfo(String buildNumber, @JsonProperty("git.commit.id.abbrev") String commitHashAbbrev, @JsonProperty("git.commit.id") String commitHash,
-    @AllArgsConstructor
+                              @JsonProperty("git.branch") String branchName, @JsonProperty("git.remote.origin.url") String originUrl) {
-    public static class GitInfo {
-        private final String buildNumber;
-        @JsonProperty("git.commit.id.abbrev")
-        private final String commitHashAbbrev;
-        @JsonProperty("git.commit.id")
-        private final String commitHash;
-        @JsonProperty("git.branch")
-        private final String branchName;
-        @JsonProperty("git.remote.origin.url")
-        private final String originUrl;
     }
 }

core/src/main/java/org/geysermc/geyser/entity/EntityDefinition.java

@@ -59,6 +59,7 @@ public record EntityDefinition<T extends Entity>(EntityFactory<T> factory, Entit
         return new Builder<>(factory);
     }
 
+    @SuppressWarnings("unchecked")
     public <M> void translateMetadata(T entity, EntityMetadata<M, ? extends MetadataType<M>> metadata) {
         EntityMetadataTranslator<? super T, M, EntityMetadata<M, ? extends MetadataType<M>>> translator = (EntityMetadataTranslator<? super T, M, EntityMetadata<M, ? extends MetadataType<M>>>) this.translators.get(metadata.getId());
         if (translator == null) {

core/src/main/java/org/geysermc/geyser/entity/attribute/GeyserAttributeType.java

@@ -25,6 +25,7 @@
 
 package org.geysermc.geyser.entity.attribute;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.protocol.bedrock.data.AttributeData;
 import lombok.AllArgsConstructor;
 import lombok.Getter;
@@ -69,7 +70,7 @@ public enum GeyserAttributeType {
         return getAttribute(value, maximum);
     }
 
-    public AttributeData getAttribute(float value, float maximum) {
+    public @Nullable AttributeData getAttribute(float value, float maximum) {
         if (bedrockIdentifier == null) {
             return null;
         }

core/src/main/java/org/geysermc/geyser/entity/type/AreaEffectCloudEntity.java

@@ -34,7 +34,6 @@ import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
 import org.geysermc.geyser.registry.Registries;
-import org.geysermc.geyser.registry.type.ParticleMapping;
 import org.geysermc.geyser.session.GeyserSession;
 
 import java.util.UUID;

core/src/main/java/org/geysermc/geyser/entity/type/Entity.java

@@ -36,6 +36,7 @@ import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.Setter;
 import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.math.vector.Vector2f;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
@@ -580,7 +581,7 @@ public class Entity implements GeyserEntity {
     }
 
     @SuppressWarnings("unchecked")
-    public <I extends Entity> I as(Class<I> entityClass) {
+    public <I extends Entity> @Nullable I as(Class<I> entityClass) {
         return entityClass.isInstance(this) ? (I) this : null;
     }
 }

core/src/main/java/org/geysermc/geyser/entity/type/LivingEntity.java

@@ -38,6 +38,7 @@ import com.github.steveice10.opennbt.tag.builtin.StringTag;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.Setter;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.math.vector.Vector3i;
 import org.cloudburstmc.protocol.bedrock.data.AttributeData;
@@ -120,7 +121,7 @@ public class LivingEntity extends Entity {
         session.sendUpstreamPacket(attributesPacket);
     }
 
-    public Vector3i setBedPosition(EntityMetadata<Optional<Vector3i>, ?> entityMetadata) {
+    public @Nullable Vector3i setBedPosition(EntityMetadata<Optional<Vector3i>, ?> entityMetadata) {
         Optional<Vector3i> optionalPos = entityMetadata.getValue();
         if (optionalPos.isPresent()) {
             Vector3i bedPosition = optionalPos.get();

core/src/main/java/org/geysermc/geyser/entity/type/ThrowableEntity.java

@@ -51,7 +51,6 @@ public class ThrowableEntity extends Entity implements Tickable {
 
     /**
      * Updates the position for the Bedrock client.
-     *
      * Java clients assume the next positions of moving items. Bedrock needs to be explicitly told positions
      */
     @Override

core/src/main/java/org/geysermc/geyser/entity/type/living/AbstractFishEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -34,7 +35,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.EntityUtils;
 import org.geysermc.geyser.util.InteractionResult;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class AbstractFishEntity extends WaterEntity {
@@ -48,9 +48,9 @@ public class AbstractFishEntity extends WaterEntity {
         setFlag(EntityFlag.HAS_GRAVITY, false);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (EntityUtils.attemptToBucket(itemInHand)) {
             return InteractionResult.SUCCESS;
         } else {

core/src/main/java/org/geysermc/geyser/entity/type/living/AllayEntity.java

@@ -27,6 +27,7 @@ package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.BooleanEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -36,7 +37,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class AllayEntity extends MobEntity {
@@ -54,9 +54,9 @@ public class AllayEntity extends MobEntity {
         this.canDuplicate = entityMetadata.getPrimitiveValue();
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (this.canDuplicate && getFlag(EntityFlag.DANCING) && isDuplicationItem(itemInHand)) {
             // Maybe better as another tag?
             return InteractiveTag.GIVE_ITEM_TO_ALLAY;
@@ -70,9 +70,9 @@ public class AllayEntity extends MobEntity {
         }
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (this.canDuplicate && getFlag(EntityFlag.DANCING) && isDuplicationItem(itemInHand)) {
             //TOCHECK sound
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/ArmorStandEntity.java

@@ -70,7 +70,7 @@ public class ArmorStandEntity extends LivingEntity {
     private boolean primaryEntity = true;
     /**
      * Whether the entity's position must be updated to included the offset.
-     *
+     * <p>
      * This should be true when the Java server marks the armor stand as invisible, but we shrink the entity
      * to allow the nametag to appear. Basically:
      * - Is visible: this is irrelevant (false)
@@ -207,7 +207,7 @@ public class ArmorStandEntity extends LivingEntity {
      * @param negativeZToggle the flag to set true if the Z value of rotation is negative
      * @param rotation the Java rotation value
      */
-    private void onRotationUpdate(EntityDataType dataLeech, EntityFlag negativeXToggle, EntityFlag negativeYToggle, EntityFlag negativeZToggle, Vector3f rotation) {
+    private void onRotationUpdate(EntityDataType<Integer> dataLeech, EntityFlag negativeXToggle, EntityFlag negativeYToggle, EntityFlag negativeZToggle, Vector3f rotation) {
         // Indicate that rotation should be checked
         setFlag(EntityFlag.BRIBED, true);
 

core/src/main/java/org/geysermc/geyser/entity/type/living/DolphinEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.geysermc.geyser.entity.EntityDefinition;
 import org.geysermc.geyser.inventory.GeyserItemStack;
@@ -33,7 +34,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class DolphinEntity extends WaterEntity {
@@ -46,18 +46,18 @@ public class DolphinEntity extends WaterEntity {
         return true;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!itemInHand.isEmpty() && session.getTagCache().isFish(itemInHand)) {
             return InteractiveTag.FEED;
         }
         return super.testMobInteraction(hand, itemInHand);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!itemInHand.isEmpty() && session.getTagCache().isFish(itemInHand)) {
             // Feed
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/IronGolemEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
@@ -35,7 +36,6 @@ import org.geysermc.geyser.item.Items;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class IronGolemEntity extends GolemEntity {
@@ -51,9 +51,9 @@ public class IronGolemEntity extends GolemEntity {
         maxHealth = 100f;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (itemInHand.asItem() == Items.IRON_INGOT) {
             if (health < maxHealth) {
                 // Healing the iron golem

core/src/main/java/org/geysermc/geyser/entity/type/living/MobEntity.java

@@ -28,6 +28,7 @@ package org.geysermc.geyser.entity.type.living;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.ByteEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
 import lombok.Getter;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
@@ -40,7 +41,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class MobEntity extends LivingEntity {
@@ -133,13 +133,13 @@ public class MobEntity extends LivingEntity {
         return InteractionResult.PASS;
     }
 
-    @Nonnull
+    @NonNull
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         return InteractiveTag.NONE;
     }
 
-    @Nonnull
+    @NonNull
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         return InteractionResult.PASS;
     }
 

core/src/main/java/org/geysermc/geyser/entity/type/living/SnowGolemEntity.java

@@ -27,6 +27,7 @@ package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.ByteEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -36,7 +37,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class SnowGolemEntity extends GolemEntity {
@@ -51,9 +51,9 @@ public class SnowGolemEntity extends GolemEntity {
         setFlag(EntityFlag.SHEARED, (xd & 0x10) != 0x10);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (Items.SHEARS == itemInHand.asItem() && isAlive() && !getFlag(EntityFlag.SHEARED)) {
             // Shearing the snow golem
             return InteractiveTag.SHEAR;
@@ -61,9 +61,9 @@ public class SnowGolemEntity extends GolemEntity {
         return InteractiveTag.NONE;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (Items.SHEARS == itemInHand.asItem() && isAlive() && !getFlag(EntityFlag.SHEARED)) {
             // Shearing the snow golem
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/TadpoleEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.geysermc.geyser.entity.EntityDefinition;
 import org.geysermc.geyser.inventory.GeyserItemStack;
@@ -34,7 +35,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class TadpoleEntity extends AbstractFishEntity {
@@ -42,18 +42,18 @@ public class TadpoleEntity extends AbstractFishEntity {
         super(session, entityId, geyserId, uuid, definition, position, motion, yaw, pitch, headYaw);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (isFood(itemInHand)) {
             return InteractiveTag.FEED;
         }
         return super.testMobInteraction(hand, itemInHand);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (isFood(itemInHand)) {
             //TODO particles
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/AnimalEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living.animal;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityEventType;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
@@ -38,7 +39,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class AnimalEntity extends AgeableEntity {
@@ -59,18 +59,18 @@ public class AnimalEntity extends AgeableEntity {
         return item == Items.WHEAT;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (canEat(itemInHand)) {
             return InteractiveTag.FEED;
         }
         return super.testMobInteraction(hand, itemInHand);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (canEat(itemInHand)) {
             // FEED
             if (getFlag(EntityFlag.BABY)) {

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/AxolotlEntity.java

@@ -28,6 +28,7 @@ package org.geysermc.geyser.entity.type.living.animal;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.BooleanEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.IntEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
@@ -38,7 +39,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.EntityUtils;
 import org.geysermc.geyser.util.InteractionResult;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class AxolotlEntity extends AnimalEntity {
@@ -74,9 +74,9 @@ public class AxolotlEntity extends AnimalEntity {
         return true;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (EntityUtils.attemptToBucket(itemInHand)) {
             return InteractionResult.SUCCESS;
         } else {

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/CowEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living.animal;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.SoundEvent;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
@@ -36,7 +37,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class CowEntity extends AnimalEntity {
@@ -44,9 +44,9 @@ public class CowEntity extends AnimalEntity {
         super(session, entityId, geyserId, uuid, definition, position, motion, yaw, pitch, headYaw);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (getFlag(EntityFlag.BABY) || itemInHand.asItem() != Items.BUCKET) {
             return super.testMobInteraction(hand, itemInHand);
         }
@@ -54,9 +54,9 @@ public class CowEntity extends AnimalEntity {
         return InteractiveTag.MILK;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (getFlag(EntityFlag.BABY) || itemInHand.asItem() != Items.BUCKET) {
             return super.mobInteract(hand, itemInHand);
         }

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/GoatEntity.java

@@ -28,6 +28,7 @@ package org.geysermc.geyser.entity.type.living.animal;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.Pose;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.BooleanEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.SoundEvent;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
@@ -38,7 +39,6 @@ import org.geysermc.geyser.item.Items;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class GoatEntity extends AnimalEntity {
@@ -70,9 +70,9 @@ public class GoatEntity extends AnimalEntity {
 
     // TODO testMobInteraction?
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!getFlag(EntityFlag.BABY) && itemInHand.asItem() == Items.BUCKET) {
             session.playSoundEvent(isScreamer ? SoundEvent.MILK_SCREAMER : SoundEvent.MILK, position);
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/MooshroomEntity.java

@@ -27,6 +27,7 @@ package org.geysermc.geyser.entity.type.living.animal;
 
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.ObjectEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -37,7 +38,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class MooshroomEntity extends AnimalEntity {
@@ -52,9 +52,9 @@ public class MooshroomEntity extends AnimalEntity {
         dirtyMetadata.put(EntityDataTypes.VARIANT, isBrown ? 1 : 0);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!isBaby()) {
             if (itemInHand.asItem() == Items.BOWL) {
                 // Stew
@@ -67,9 +67,9 @@ public class MooshroomEntity extends AnimalEntity {
         return super.testMobInteraction(hand, itemInHand);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         boolean isBaby = isBaby();
         if (!isBaby && itemInHand.asItem() == Items.BOWL) {
             // Stew

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/OcelotEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living.animal;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -36,7 +37,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class OcelotEntity extends AnimalEntity {
@@ -50,9 +50,9 @@ public class OcelotEntity extends AnimalEntity {
         return item == Items.COD || item == Items.SALMON;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!getFlag(EntityFlag.TRUSTING) && canEat(itemInHand) && session.getPlayerEntity().getPosition().distanceSquared(position) < 9f) {
             // Attempt to feed
             return InteractiveTag.FEED;
@@ -61,9 +61,9 @@ public class OcelotEntity extends AnimalEntity {
         }
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!getFlag(EntityFlag.TRUSTING) && canEat(itemInHand) && session.getPlayerEntity().getPosition().distanceSquared(position) < 9f) {
             // Attempt to feed
             return InteractionResult.SUCCESS;

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/PandaEntity.java

@@ -28,6 +28,8 @@ package org.geysermc.geyser.entity.type.living.animal;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.ByteEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.metadata.type.IntEntityMetadata;
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityEventType;
@@ -41,8 +43,6 @@ import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 import java.util.UUID;
 
 public class PandaEntity extends AnimalEntity {
@@ -93,18 +93,18 @@ public class PandaEntity extends AnimalEntity {
         return item == Items.BAMBOO;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (mainGene == Gene.WORRIED && session.isThunder()) {
             return InteractiveTag.NONE;
         }
         return super.testMobInteraction(hand, itemInHand);
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (mainGene == Gene.WORRIED && session.isThunder()) {
             // Huh!
             return InteractionResult.PASS;

core/src/main/java/org/geysermc/geyser/entity/type/living/animal/PigEntity.java

@@ -26,6 +26,7 @@
 package org.geysermc.geyser.entity.type.living.animal;
 
 import com.github.steveice10.mc.protocol.data.game.entity.player.Hand;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
@@ -37,7 +38,6 @@ import org.geysermc.geyser.util.EntityUtils;
 import org.geysermc.geyser.util.InteractionResult;
 import org.geysermc.geyser.util.InteractiveTag;
 
-import javax.annotation.Nonnull;
 import java.util.UUID;
 
 public class PigEntity extends AnimalEntity {
@@ -51,9 +51,9 @@ public class PigEntity extends AnimalEntity {
         return item == Items.CARROT || item == Items.POTATO || item == Items.BEETROOT;
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractiveTag testMobInteraction(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractiveTag testMobInteraction(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!canEat(itemInHand) && getFlag(EntityFlag.SADDLED) && passengers.isEmpty() && !session.isSneaking()) {
             // Mount
             return InteractiveTag.MOUNT;
@@ -68,9 +68,9 @@ public class PigEntity extends AnimalEntity {
         }
     }
 
-    @Nonnull
+    @NonNull
     @Override
-    protected InteractionResult mobInteract(@Nonnull Hand hand, @Nonnull GeyserItemStack itemInHand) {
+    protected InteractionResult mobInteract(@NonNull Hand hand, @NonNull GeyserItemStack itemInHand) {
         if (!canEat(itemInHand) && getFlag(EntityFlag.SADDLED) && passengers.isEmpty() && !session.isSneaking()) {
             // Mount
             return InteractionResult.SUCCESS;