feat: alter clipboard thread to move all clipboard loading from main thread (#2867)

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

@@ -564,17 +564,17 @@ public class WorldEditPlugin extends JavaPlugin {
     public BukkitPlayer wrapPlayer(Player player) {
         //FAWE start - Use cache over returning a direct BukkitPlayer
         BukkitPlayer wePlayer = getCachedPlayer(player);
-        if (wePlayer == null) {
-            synchronized (player) {
-                wePlayer = getCachedPlayer(player);
-                if (wePlayer == null) {
-                    wePlayer = new BukkitPlayer(this, player);
-                    player.setMetadata("WE", new FixedMetadataValue(this, wePlayer));
-                    return wePlayer;
-                }
-            }
+        if (wePlayer != null) {
+            return wePlayer;
+        }
+        synchronized (player) {
+            BukkitPlayer bukkitPlayer = getCachedPlayer(player);
+            if (bukkitPlayer == null) {
+                bukkitPlayer = new BukkitPlayer(this, player);
+                player.setMetadata("WE", new FixedMetadataValue(this, bukkitPlayer));
+            }
+            return bukkitPlayer;
         }
-        return wePlayer;
         //FAWE end
     }
 

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

@@ -14,8 +14,8 @@ import com.fastasyncworldedit.core.util.TaskManager;
 import com.fastasyncworldedit.core.util.TextureUtil;
 import com.fastasyncworldedit.core.util.WEManager;
 import com.fastasyncworldedit.core.util.task.KeyQueuedExecutorService;
+import com.fastasyncworldedit.core.util.task.UUIDKeyQueuedThreadFactory;
 import com.github.luben.zstd.Zstd;
-import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.internal.util.LogManagerCompat;
 import net.jpountz.lz4.LZ4Factory;
@@ -37,6 +37,9 @@ import java.lang.management.MemoryUsage;
 import java.util.Date;
 import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Future;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
@@ -92,7 +95,7 @@ public class Fawe {
      * The platform specific implementation.
      */
     private final IFawe implementation;
-    private final KeyQueuedExecutorService<UUID> clipboardExecutor;
+    private final KeyQueuedExecutorService<UUID> uuidKeyQueuedExecutorService;
     private FaweVersion version;
     private TextureUtil textures;
     private QueueHandler queueHandler;
@@ -140,14 +143,13 @@ public class Fawe {
         }, 0);
 
         TaskManager.taskManager().repeat(timer, 1);
-
-        clipboardExecutor = new KeyQueuedExecutorService<>(new ThreadPoolExecutor(
+        uuidKeyQueuedExecutorService = new KeyQueuedExecutorService<>(new ThreadPoolExecutor(
                 1,
                 Settings.settings().QUEUE.PARALLEL_THREADS,
                 0L,
                 TimeUnit.MILLISECONDS,
                 new LinkedBlockingQueue<>(),
-                new ThreadFactoryBuilder().setNameFormat("FAWE Clipboard - %d").build()
+                new UUIDKeyQueuedThreadFactory()
         ));
     }
 
@@ -463,9 +465,58 @@ public class Fawe {
      *
      * @return Executor used for clipboard IO if clipboard on disk is enabled or null
      * @since 2.6.2
+     * @deprecated Use any of {@link Fawe#submitUUIDKeyQueuedTask(UUID, Runnable)},
+     * {@link Fawe#submitUUIDKeyQueuedTask(UUID, Runnable, Object), {@link Fawe#submitUUIDKeyQueuedTask(UUID, Callable)}
+     * to ensure if a thread is already a UUID-queued thread, the task is immediately run
      */
+    @Deprecated(forRemoval = true, since = "TODO")
     public KeyQueuedExecutorService<UUID> getClipboardExecutor() {
-        return this.clipboardExecutor;
+        return this.uuidKeyQueuedExecutorService;
+    }
+
+    /**
+     * Submit a task to the UUID key-queued executor
+     *
+     * @return Future representing the tank
+     * @since TODO
+     */
+    public Future<?> submitUUIDKeyQueuedTask(UUID uuid, Runnable runnable) {
+        if (Thread.currentThread() instanceof UUIDKeyQueuedThreadFactory.UUIDKeyQueuedThread) {
+            runnable.run();
+            return CompletableFuture.completedFuture(null);
+        }
+        return this.uuidKeyQueuedExecutorService.submit(uuid, runnable);
+    }
+
+    /**
+     * Submit a task to the UUID key-queued executor
+     *
+     * @return Future representing the tank
+     * @since TODO
+     */
+    public <T> Future<T> submitUUIDKeyQueuedTask(UUID uuid, Runnable runnable, T result) {
+        if (Thread.currentThread() instanceof UUIDKeyQueuedThreadFactory.UUIDKeyQueuedThread) {
+            runnable.run();
+            return CompletableFuture.completedFuture(result);
+        }
+        return this.uuidKeyQueuedExecutorService.submit(uuid, runnable, result);
+    }
+
+    /**
+     * Submit a task to the UUID key-queued executor
+     *
+     * @return Future representing the tank
+     * @since TODO
+     */
+    public <T> Future<T> submitUUIDKeyQueuedTask(UUID uuid, Callable<T> callable) {
+        if (Thread.currentThread() instanceof UUIDKeyQueuedThreadFactory.UUIDKeyQueuedThread) {
+            try {
+                return CompletableFuture.completedFuture(callable.call());
+            } catch (Throwable t) {
+                return CompletableFuture.failedFuture(t);
+            }
+        }
+        return this.uuidKeyQueuedExecutorService.submit(uuid, callable);
     }
 
 }

worldedit-core/src/main/java/com/fastasyncworldedit/core/util/task/UUIDKeyQueuedThreadFactory.java

@@ -0,0 +1,41 @@
+package com.fastasyncworldedit.core.util.task;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicInteger;
+
+@ApiStatus.Internal
+public class UUIDKeyQueuedThreadFactory implements ThreadFactory {
+
+    private final ThreadGroup group;
+    private final AtomicInteger threadNumber = new AtomicInteger(1);
+    private final String namePrefix;
+
+    public UUIDKeyQueuedThreadFactory() {
+        group = new ThreadGroup("UUIDKeyQueuedThreadGroup");
+        namePrefix = "FAWE UUID-key-queued - ";
+    }
+
+    public Thread newThread(@Nonnull Runnable r) {
+        Thread t = new UUIDKeyQueuedThread(group, r, namePrefix + threadNumber.getAndIncrement(), 0);
+        if (t.isDaemon()) {
+            t.setDaemon(false);
+        }
+        if (t.getPriority() != Thread.NORM_PRIORITY) {
+            t.setPriority(Thread.NORM_PRIORITY);
+        }
+        return t;
+    }
+
+    public static final class UUIDKeyQueuedThread extends Thread {
+
+        public UUIDKeyQueuedThread(@Nullable ThreadGroup group, Runnable task, @Nonnull String name, long stackSize) {
+            super(group, task, name, stackSize);
+        }
+
+    }
+
+}

worldedit-core/src/main/java/com/sk89q/worldedit/LocalSession.java

@@ -930,7 +930,7 @@ public class LocalSession implements TextureHolder {
                     }
                 } catch (EmptyClipboardException ignored) {
                 }
-                DiskOptimizedClipboard doc = Fawe.instance().getClipboardExecutor().submit(
+                DiskOptimizedClipboard doc = Fawe.instance().submitUUIDKeyQueuedTask(
                         uuid,
                         () -> DiskOptimizedClipboard.loadFromFile(file)
                 ).get();
@@ -954,7 +954,7 @@ public class LocalSession implements TextureHolder {
                     } else {
                         continue;
                     }
-                    Fawe.instance().getClipboardExecutor().submit(uuid, () -> {
+                    Fawe.instance().submitUUIDKeyQueuedTask(uuid, () -> {
                         doc.close(); // Ensure closed before deletion
                         doc.getFile().delete();
                     });

worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java

@@ -325,7 +325,7 @@ public class ClipboardCommands {
             } else {
                 throw e;
             }
-            Fawe.instance().getClipboardExecutor().submit(actor.getUniqueId(), () -> {
+            Fawe.instance().submitUUIDKeyQueuedTask(actor.getUniqueId(), () -> {
                 clipboard.close();
                 doc.getFile().delete();
             });

worldedit-core/src/main/java/com/sk89q/worldedit/entity/Player.java

@@ -423,7 +423,7 @@ public interface Player extends Entity, Actor {
         if (Settings.settings().CLIPBOARD.USE_DISK && Settings.settings().CLIPBOARD.DELETE_ON_LOGOUT) {
             session.deleteClipboardOnDisk();
         } else if (Settings.settings().CLIPBOARD.USE_DISK) {
-            Fawe.instance().getClipboardExecutor().submit(getUniqueId(), () -> session.setClipboard(null));
+            Fawe.instance().submitUUIDKeyQueuedTask(getUniqueId(), () -> session.setClipboard(null));
         } else if (Settings.settings().CLIPBOARD.DELETE_ON_LOGOUT) {
             session.setClipboard(null);
         }
@@ -436,32 +436,8 @@ public interface Player extends Entity, Actor {
     void sendTitle(Component title, Component sub);
 
     /**
-     * Loads any history items from disk: - Should already be called if history on disk is enabled.
+     * Loads clipboard file from disk if it exists
      */
-    default void loadClipboardFromDisk() {
-        File file = MainUtil.getFile(
-                Fawe.platform().getDirectory(),
-                Settings.settings().PATHS.CLIPBOARD + File.separator + getUniqueId() + ".bd"
-        );
-        try {
-            getSession().loadClipboardFromDisk(file);
-        } catch (FaweClipboardVersionMismatchException e) {
-            print(e.getComponent());
-        } catch (RuntimeException e) {
-            print(Caption.of("fawe.error.clipboard.invalid"));
-            e.printStackTrace();
-            print(Caption.of("fawe.error.stacktrace"));
-            print(Caption.of("fawe.error.clipboard.load.failure"));
-            print(Caption.of("fawe.error.clipboard.invalid.info", file.getName(), file.length()));
-            print(Caption.of("fawe.error.stacktrace"));
-        } catch (Exception e) {
-            print(Caption.of("fawe.error.clipboard.invalid"));
-            e.printStackTrace();
-            print(Caption.of("fawe.error.stacktrace"));
-            print(Caption.of("fawe.error.no-failure"));
-            print(Caption.of("fawe.error.clipboard.invalid.info", file.getName(), file.length()));
-            print(Caption.of("fawe.error.stacktrace"));
-        }
-    }
+    void loadClipboardFromDisk();
     //FAWE end
 }

worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/AbstractPlayerActor.java

@@ -19,10 +19,14 @@
 
 package com.sk89q.worldedit.extension.platform;
 
+import com.fastasyncworldedit.core.Fawe;
 import com.fastasyncworldedit.core.configuration.Caption;
+import com.fastasyncworldedit.core.configuration.Settings;
+import com.fastasyncworldedit.core.internal.exception.FaweClipboardVersionMismatchException;
 import com.fastasyncworldedit.core.internal.exception.FaweException;
 import com.fastasyncworldedit.core.math.MutableBlockVector3;
 import com.fastasyncworldedit.core.regions.FaweMaskManager;
+import com.fastasyncworldedit.core.util.MainUtil;
 import com.fastasyncworldedit.core.util.TaskManager;
 import com.fastasyncworldedit.core.util.WEManager;
 import com.fastasyncworldedit.core.util.task.AsyncNotifyKeyedQueue;
@@ -69,6 +73,8 @@ import javax.annotation.Nullable;
 import java.io.File;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Future;
+import java.util.concurrent.Semaphore;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
@@ -82,6 +88,7 @@ public abstract class AbstractPlayerActor implements Actor, Player, Cloneable {
 
     //FAWE start
     private final Map<String, Object> meta;
+    private final Semaphore clipboardLoading = new Semaphore(1);
 
     // Queue for async tasks
     private final AtomicInteger runningCount = new AtomicInteger();
@@ -524,22 +531,68 @@ public abstract class AbstractPlayerActor implements Actor, Player, Cloneable {
 
     @Override
     public void setSelection(Region region) {
-        RegionSelector selector;
-        if (region instanceof ConvexPolyhedralRegion) {
-            selector = new ConvexPolyhedralRegionSelector((ConvexPolyhedralRegion) region);
-        } else if (region instanceof CylinderRegion) {
-            selector = new CylinderRegionSelector((CylinderRegion) region);
-        } else if (region instanceof Polygonal2DRegion) {
-            selector = new Polygonal2DRegionSelector((Polygonal2DRegion) region);
-        } else {
-            selector = new CuboidRegionSelector(null, region.getMinimumPoint(),
-                    region.getMaximumPoint()
-            );
-        }
+        RegionSelector selector = switch (region) {
+            case ConvexPolyhedralRegion blockVector3s -> new ConvexPolyhedralRegionSelector(blockVector3s);
+            case CylinderRegion blockVector3s -> new CylinderRegionSelector(blockVector3s);
+            case Polygonal2DRegion blockVector3s -> new Polygonal2DRegionSelector(blockVector3s);
+            default -> new CuboidRegionSelector(null, region.getMinimumPoint(), region.getMaximumPoint());
+        };
         selector.setWorld(region.getWorld());
 
         getSession().setRegionSelector(getWorld(), selector);
     }
+
+    @Override
+    public void loadClipboardFromDisk() {
+        if (!clipboardLoading.tryAcquire()) {
+            if (!Fawe.isMainThread()) {
+                try {
+                    clipboardLoading.acquire();
+                    clipboardLoading.release();
+                } catch (InterruptedException e) {
+                    LOGGER.error("Error waiting for clipboard-on-disk loading for player {}", getName(), e);
+                }
+            }
+            return;
+        }
+
+        File file = MainUtil.getFile(
+                Fawe.platform().getDirectory(),
+                Settings.settings().PATHS.CLIPBOARD + File.separator + getUniqueId() + ".bd"
+        );
+        try {
+            Future<?> fut = Fawe.instance().submitUUIDKeyQueuedTask(getUniqueId(), () -> {
+                try {
+                    getSession().loadClipboardFromDisk(file);
+                } catch (FaweClipboardVersionMismatchException e) {
+                    print(e.getComponent());
+                } catch (RuntimeException e) {
+                    print(Caption.of("fawe.error.clipboard.invalid"));
+                    LOGGER.error("Error loading clipboard from disk", e);
+                    print(Caption.of("fawe.error.stacktrace"));
+                    print(Caption.of("fawe.error.clipboard.load.failure"));
+                    print(Caption.of("fawe.error.clipboard.invalid.info", file.getName(), file.length()));
+                    print(Caption.of("fawe.error.stacktrace"));
+                } catch (Exception e) {
+                    print(Caption.of("fawe.error.clipboard.invalid"));
+                    LOGGER.error("Error loading clipboard from disk", e);
+                    print(Caption.of("fawe.error.stacktrace"));
+                    print(Caption.of("fawe.error.no-failure"));
+                    print(Caption.of("fawe.error.clipboard.invalid.info", file.getName(), file.length()));
+                    print(Caption.of("fawe.error.stacktrace"));
+                } finally {
+                    clipboardLoading.release();
+                }
+            });
+            if (Fawe.isMainThread()) {
+                return;
+            }
+            fut.get();
+        } catch (Exception e) {
+            LOGGER.error("Error loading clipboard from disk", e);
+            print(Caption.of("fawe.error.clipboard.load.failure"));
+        }
+    }
     //FAWE end
 
     @Override
@@ -698,10 +751,9 @@ public abstract class AbstractPlayerActor implements Actor, Player, Cloneable {
 
     @Override
     public boolean equals(Object other) {
-        if (!(other instanceof Player)) {
+        if (!(other instanceof Player other2)) {
             return false;
         }
-        Player other2 = (Player) other;
         return other2.getName().equals(getName());
     }
 

worldedit-core/src/main/resources/lang/strings.json

@@ -132,7 +132,7 @@
   "fawe.error.parse.no-clipboard-source": "No clipboards found at given source: {0}",
   "fawe.error.clipboard.invalid": "====== INVALID CLIPBOARD ======",
   "fawe.error.clipboard.invalid.info": "File: {0} (len: {1})",
-  "fawe.error.clipboard.load.failure": "Could not load clipboard. Possible that the clipboard is still being written to from another server?!",
+  "fawe.error.clipboard.load.failure": "Unexpected failure loading clipboard from disk!",
   "fawe.error.clipboard.on.disk.version.mismatch": "Clipboard version mismatch: expected {0} but got {1}. It is recommended you delete the clipboard folder and restart the server.\nYour clipboard folder is located at {2}.",
   "fawe.error.limit.disallowed-block": "Your limit disallows use of block '{0}'",
   "fawe.error.limit.disallowed-property": "Your limit disallows use of property '{0}'",