Modernize instanceof checks, switch expressions, and error handling

gradle/libs.versions.toml

@@ -57,6 +57,10 @@ shadow = "9.5.1"
 paperweight = "2.0.0-SNAPSHOT"
 codecov = "0.3.0"
 jqwik = "1.10.1"
+errorproneGradlePlugin = "5.1.0"
+
+# Error Prone
+errorprone = "2.50.0"
 
 # Minimum versions we apply to make dependencies support newer Java
 minimumAsm = "9.7"
@@ -66,6 +70,7 @@ minimumJdependency = "2.10"
 # Gradle plugins
 shadow = { group = "com.gradleup.shadow", name = "shadow-gradle-plugin", version.ref = "shadow" }
 paperweight = { group = "io.papermc.paperweight.userdev", name = "io.papermc.paperweight.userdev.gradle.plugin", version.ref = "paperweight" }
+errorproneGradlePlugin = { group = "net.ltgt.gradle", name = "gradle-errorprone-plugin", version.ref = "errorproneGradlePlugin" }
 
 # Minecraft expectations
 paperApi = { group = "io.papermc.paper", name = "paper-api", version.ref = "paperApi" }
@@ -143,6 +148,9 @@ mockito-junit-jupiter = { group = "org.mockito", name = "mockito-core" }
 
 log4j-core = { group = "org.apache.logging.log4j", name = "log4j-core", version.ref = "log4j" }
 
+errorprone-core = { group = "com.google.errorprone", name = "error_prone_core", version.ref = "errorprone" }
+errorprone-annotations = { group = "com.google.errorprone", name = "error_prone_annotations", version.ref = "errorprone" }
+
 ## Piston
 [libraries.piston-core]
 module = "org.enginehub.piston:core"

worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/regions/plotsquared/FaweDelegateSchematicHandler.java

@@ -177,8 +177,7 @@ public boolean save(CompoundTag tag, String path) {
         try {
             File tmp = FileUtils.getFile(PlotSquared.platform().getDirectory(), path);
             tmp.getParentFile().mkdirs();
-            if (tag instanceof CompressedCompoundTag) {
-                CompressedCompoundTag cTag = (CompressedCompoundTag) tag;
+            if (tag instanceof CompressedCompoundTag cTag) {
                 if (cTag instanceof CompressedSchematicTag) {
                     Clipboard clipboard = (Clipboard) cTag.getSource();
                     try (OutputStream stream = new FileOutputStream(tmp);

worldedit-bukkit/src/main/java/com/sk89q/wepif/DinnerPermsResolver.java

@@ -78,22 +78,26 @@ public boolean hasPermission(OfflinePlayer player, String permission) {
             return false; // Permissions are only registered for objects with a Permissible
         }
         switch (internalHasPermission(perms, permission)) {
-            case -1:
+            case -1 -> {
                 return false;
-            case 1:
+            }
+            case 1 -> {
                 return true;
-            default:
-                break;
+            }
+            default -> {
+            }
         }
         int dotPos = permission.lastIndexOf(".");
         while (dotPos > -1) {
             switch (internalHasPermission(perms, permission.substring(0, dotPos + 1) + "*")) {
-                case -1:
+                case -1 -> {
                     return false;
-                case 1:
+                }
+                case 1 -> {
                     return true;
-                default:
-                    break;
+                }
+                default -> {
+                }
             }
             dotPos = permission.lastIndexOf(".", dotPos - 1);
         }

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitAdapter.java

@@ -153,12 +153,11 @@ public static BukkitPlayer adapt(Player player) {
      * @return The Bukkit command sender
      */
     public static CommandSender adapt(Actor actor) {
-        if (actor instanceof com.sk89q.worldedit.entity.Player) {
-            return adapt((com.sk89q.worldedit.entity.Player) actor);
-        } else if (actor instanceof BukkitBlockCommandSender) {
-            return ((BukkitBlockCommandSender) actor).getSender();
-        }
-        return ((BukkitCommandSender) actor).getSender();
+        return switch (actor) {
+            case com.sk89q.worldedit.entity.Player player -> adapt(player);
+            case BukkitBlockCommandSender bukkitBlockCommandSender -> bukkitBlockCommandSender.getSender();
+            case null, default -> ((BukkitCommandSender) actor).getSender();
+        };
     }
 
     /**
@@ -181,24 +180,15 @@ public static Player adapt(com.sk89q.worldedit.entity.Player player) {
      * @return a WorldEdit direction
      */
     public static Direction adapt(@Nullable BlockFace face) {
-        if (face == null) {
-            return null;
-        }
-        switch (face) {
-            case NORTH:
-                return Direction.NORTH;
-            case SOUTH:
-                return Direction.SOUTH;
-            case WEST:
-                return Direction.WEST;
-            case EAST:
-                return Direction.EAST;
-            case DOWN:
-                return Direction.DOWN;
-            case UP:
-            default:
-                return Direction.UP;
-        }
+        return switch (face) {
+            case null -> null;
+            case NORTH -> Direction.NORTH;
+            case SOUTH -> Direction.SOUTH;
+            case WEST -> Direction.WEST;
+            case EAST -> Direction.EAST;
+            case DOWN -> Direction.DOWN;
+            default -> Direction.UP;
+        };
     }
 
     /**

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitBlockRegistry.java

@@ -117,14 +117,10 @@ public BukkitBlockMaterial(@Nullable BlockMaterial material, Material bukkitMate
 
         @Override
         public boolean isAir() {
-            switch (material) {
-                case AIR:
-                case CAVE_AIR:
-                case VOID_AIR:
-                    return true;
-                default:
-                    return false;
-            }
+            return switch (material) {
+                case AIR, CAVE_AIR, VOID_AIR -> true;
+                default -> false;
+            };
         }
 
         @Override

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitCommandSender.java

@@ -144,8 +144,7 @@ public String getName() {
             @Override
             public boolean isActive() {
                 //FAWE start - check if sender instanceof Entity, before returning true
-                if (sender instanceof Entity) {
-                    Entity entity = (Entity) sender;
+                if (sender instanceof Entity entity) {
                     return entity.isValid() && !entity.isDead();
                 }
                 //FAWE end

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitEntityProperties.java

@@ -148,7 +148,7 @@ public boolean isGolem() {
 
     @Override
     public boolean isTamed() {
-        return entity instanceof Tameable && ((Tameable) entity).isTamed();
+        return entity instanceof Tameable tameable && tameable.isTamed();
     }
 
     @Override

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitPlayer.java

@@ -234,8 +234,7 @@ public void print(Component component) {
     public boolean trySetPosition(Vector3 pos, float pitch, float yaw) {
         //FAWE start
         org.bukkit.World world = player.getWorld();
-        if (pos instanceof com.sk89q.worldedit.util.Location) {
-            com.sk89q.worldedit.util.Location loc = (com.sk89q.worldedit.util.Location) pos;
+        if (pos instanceof com.sk89q.worldedit.util.Location loc) {
             Extent extent = loc.getExtent();
             if (extent instanceof World) {
                 world = Bukkit.getWorld(((World) extent).getName());

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitPlayerBlockBag.java

@@ -201,7 +201,7 @@ public BaseItem getItem(int slot) {
     @Override
     public void setItem(int slot, BaseItem block) {
         loadInventory();
-        BaseItemStack stack = block instanceof BaseItemStack ? (BaseItemStack) block : new BaseItemStack(
+        BaseItemStack stack = block instanceof BaseItemStack baseItemStack ? baseItemStack : new BaseItemStack(
                 block.getType(),
                 block.getNbtData(),
                 1

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitWorld.java

@@ -304,8 +304,8 @@ public boolean clearContainerBlockContents(BlockVector3 pt) {
 
         TaskManager.taskManager().sync(() -> {
             Inventory inven = chest.getInventory();
-            if (chest instanceof Chest) {
-                inven = ((Chest) chest).getBlockInventory();
+            if (chest instanceof Chest chest1) {
+                inven = chest1.getBlockInventory();
             }
             inven.clear();
             return null;
@@ -416,11 +416,11 @@ public boolean equals(Object other) {
             return false;
         } else if (other == null) {
             return false;
-        } else if ((other instanceof BukkitWorld)) {
-            World otherWorld = ((BukkitWorld) other).worldRef.get();
+        } else if (other instanceof BukkitWorld bukkitWorld) {
+            World otherWorld = bukkitWorld.worldRef.get();
             return ref.equals(otherWorld);
-        } else if (other instanceof com.sk89q.worldedit.world.World) {
-            return ((com.sk89q.worldedit.world.World) other).getName().equals(ref.getName());
+        } else if (other instanceof com.sk89q.worldedit.world.World world) {
+            return world.getName().equals(ref.getName());
         } else {
             return false;
         }
@@ -610,10 +610,10 @@ public <B extends BlockStateHolder<B>> boolean setBlock(BlockVector3 position, B
             try {
                 return worldNativeAccess.setBlock(position, block, sideEffects);
             } catch (Exception e) {
-                if (block instanceof BaseBlock && ((BaseBlock) block).getNbt() != null) {
+                if (block instanceof BaseBlock baseBlock && baseBlock.getNbt() != null) {
                     LOGGER.warn(
                             "Tried to set a corrupt tile entity at " + position.toString()
-                                    + ": " + ((BaseBlock) block).getNbt(), e
+                                    + ": " + baseBlock.getNbt(), e
                     );
                 } else {
                     LOGGER.warn("Failed to set block via adapter, falling back to generic", e);

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditListener.java

@@ -159,23 +159,13 @@ public void onPlayerInteract(PlayerInteractEvent event) {
         final Block clickedBlock = event.getClickedBlock();
         final Location pos = clickedBlock == null ? null : new Location(world, clickedBlock.getX(), clickedBlock.getY(), clickedBlock.getZ());
 
-        boolean result = false;
-        switch (event.getAction()) {
-            case LEFT_CLICK_BLOCK:
-                result = we.handleBlockLeftClick(player, pos, direction) || we.handleArmSwing(player);
-                break;
-            case LEFT_CLICK_AIR:
-                result = we.handleArmSwing(player);
-                break;
-            case RIGHT_CLICK_BLOCK:
-                result = we.handleBlockRightClick(player, pos, direction) || we.handleRightClick(player);
-                break;
-            case RIGHT_CLICK_AIR:
-                result = we.handleRightClick(player);
-                break;
-            default:
-                break;
-        }
+        boolean result = switch (event.getAction()) {
+            case LEFT_CLICK_BLOCK -> we.handleBlockLeftClick(player, pos, direction) || we.handleArmSwing(player);
+            case LEFT_CLICK_AIR -> we.handleArmSwing(player);
+            case RIGHT_CLICK_BLOCK -> we.handleBlockRightClick(player, pos, direction) || we.handleRightClick(player);
+            case RIGHT_CLICK_AIR -> we.handleRightClick(player);
+            default -> false;
+        };
         debouncer.setLastInteraction(player, result);
         if (result) {
             event.setCancelled(true);

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java

@@ -644,10 +644,10 @@ BukkitPlayer reCachePlayer(Player player) {
     //FAWE end
 
     public Actor wrapCommandSender(CommandSender sender) {
-        if (sender instanceof Player) {
-            return wrapPlayer((Player) sender);
-        } else if (config.commandBlockSupport && sender instanceof BlockCommandSender) {
-            return new BukkitBlockCommandSender(this, (BlockCommandSender) sender);
+        if (sender instanceof Player player) {
+            return wrapPlayer(player);
+        } else if (config.commandBlockSupport && sender instanceof BlockCommandSender blockCommandSender) {
+            return new BukkitBlockCommandSender(this, blockCommandSender);
         }
 
         return bukkitConsoleCommandSender;

worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/BukkitImplLoader.java

@@ -50,15 +50,19 @@ public class BukkitImplLoader {
     private static final String CLASS_SUFFIX = ".class";
 
     private static final String LOAD_ERROR_MESSAGE =
-            //FAWE start - exchange WorldEdit to FAWE & suggest to update Fawe & the server software
-            "\n**********************************************\n"
-                    + "** This FastAsyncWorldEdit version does not fully support your version of Bukkit.\n"
-                    + "** You can fix this by:\n"
-                    + "** - Updating your server version (Check /version to see how many versions you are behind)\n** - Updating FAWE\n"
-                    + "**\n" + "** When working with blocks or undoing, chests will be empty, signs\n"
-                    + "** will be blank, and so on. There will be no support for entity\n"
-                    + "** and block property-related functions.\n"
-                    + "**********************************************\n";
+            //FAWE start - exchange WorldEdit to FAWE & suggest to update FAWE & the server software
+            """  
+            **********************************************
+            ** This FastAsyncWorldEdit version does not fully support your version of Bukkit.
+            ** You can fix this by:
+            ** - Updating your server version (Check /version to see how many versions you are behind)
+            ** - Updating FAWE
+            **
+            ** When working with blocks or undoing, chests will be empty, signs
+            ** will be blank, and so on. There will be no support for entity
+            ** and block property-related functions.
+            **********************************************
+            """;
     //FAWE end
 
     /**
@@ -89,9 +93,8 @@ private void addDefaults() {
      * @throws IOException thrown on I/O error
      */
     public void addFromJar(File file) throws IOException {
-        Closer closer = Closer.create();
+        try (Closer closer = Closer.create()) {
         JarFile jar = closer.register(new JarFile(file));
-        try {
             Enumeration<JarEntry> entries = jar.entries();
             while (entries.hasMoreElements()) {
                 JarEntry jarEntry = entries.nextElement();
@@ -111,8 +114,6 @@ public void addFromJar(File file) throws IOException {
                     adapterCandidates.add(className);
                 }
             }
-        } finally {
-            closer.close();
         }
     }
 

worldedit-cli/src/main/java/com/sk89q/worldedit/cli/CLIBlockRegistry.java

@@ -39,29 +39,26 @@
 public class CLIBlockRegistry extends BundledBlockRegistry {
 
     private Property<?> createProperty(String type, String key, List<String> values) {
-        switch (type) {
-            case "int": {
+        return switch (type) {
+            case "int" -> {
                 List<Integer> fixedValues = values.stream().map(Integer::parseInt).collect(Collectors.toList());
-                return new IntegerProperty(key, fixedValues);
+                yield new IntegerProperty(key, fixedValues);
             }
-            case "bool": {
+            case "bool" -> {
                 List<Boolean> fixedValues = values.stream().map(Boolean::parseBoolean).collect(Collectors.toList());
-                return new BooleanProperty(key, fixedValues);
+                yield new BooleanProperty(key, fixedValues);
             }
-            case "enum": {
-                return new EnumProperty(key, values);
-            }
-            case "direction": {
+            case "enum" -> new EnumProperty(key, values);
+            case "direction" -> {
                 List<Direction> fixedValues = values
                         .stream()
                         .map(String::toUpperCase)
                         .map(Direction::valueOf)
                         .collect(Collectors.toList());
-                return new DirectionalProperty(key, fixedValues);
+                yield new DirectionalProperty(key, fixedValues);
             }
-            default:
-                throw new RuntimeException("Failed to create property");
-        }
+            default -> throw new RuntimeException("Failed to create property");
+        };
     }
 
     @Nullable

worldedit-core/src/main/java/com/fastasyncworldedit/core/FaweCache.java

@@ -36,6 +36,8 @@
 import com.sk89q.worldedit.internal.util.LogManagerCompat;
 import com.sk89q.worldedit.world.block.BlockTypesCache;
 import org.apache.logging.log4j.Logger;
+import org.enginehub.linbus.tree.LinCompoundTag;
+import org.enginehub.linbus.tree.LinTag;
 
 import javax.annotation.Nonnull;
 import java.util.ArrayList;
@@ -664,9 +666,8 @@ public ThreadPoolExecutor newBlockingExecutor(String name, Logger logger) {
 
             protected synchronized void afterExecute(Runnable runnable, Throwable throwable) {
                 super.afterExecute(runnable, throwable);
-                if (throwable == null && runnable instanceof Future<?>) {
+                if (throwable == null && runnable instanceof final Future<?> future) {
                     try {
-                        Future<?> future = (Future<?>) runnable;
                         if (future.isDone()) {
                             future.get();
                         }

worldedit-core/src/main/java/com/fastasyncworldedit/core/command/tool/brush/CopyPastaBrush.java

@@ -54,10 +54,9 @@ public boolean reset() {
     public void build(EditSession editSession, BlockVector3 position, Pattern pattern, double size) throws
             MaxChangedBlocksException {
         Actor actor = editSession.getActor();
-        if (!(actor instanceof Player)) {
+        if (!(actor instanceof final Player player)) {
             throw FaweCache.PLAYER_ONLY;
         }
-        Player player = (Player) actor;
         ClipboardHolder clipboard = session.getExistingClipboard();
         if (clipboard == null) {
             Mask mask = editSession.getMask();