Implement ability to clear biome change queue.

src/main/java/world/bentobox/biomes/commands/admin/AdminCommand.java

@@ -74,6 +74,8 @@ public void setup()
         new MigrateCommand(this.getAddon(), this);
         new BiomesSetCommand(this.getAddon(), this);
         new BiomesUnlockCommand(this.getAddon(), this);
+
+        new BiomesClearQueueCommand(this.getAddon(), this);
     }
 
 
@@ -541,6 +543,52 @@ public Optional<List<String>> tabComplete(User user, String alias, List<String>
     }
 
 
+    /**
+     * The queue clear command.
+     */
+    private static class BiomesClearQueueCommand extends CompositeCommand
+    {
+        /**
+         * Migrates biomes
+         *
+         * @param addon - addon
+         * @param cmd - command
+         */
+        public BiomesClearQueueCommand(Addon addon, CompositeCommand cmd)
+        {
+            super(addon, cmd, "clearqueue");
+        }
+
+
+        /**
+         * Execute command.
+         *
+         * @param user the user
+         * @param label the command top label
+         * @param args the args
+         * @return always true.
+         */
+        @Override
+        public boolean execute(User user, String label, List<String> args)
+        {
+            this.<BiomesAddon>getAddon().getAddonManager().clearQueues(user, getWorld());
+            return true;
+        }
+
+
+        /**
+         * Sets command settings.
+         */
+        @Override
+        public void setup()
+        {
+            this.inheritPermission();
+            this.setParametersHelp(Constants.ADMIN_COMMANDS + "clear-queue.parameters");
+            this.setDescription(Constants.ADMIN_COMMANDS + "clear-queue.description");
+        }
+    }
+
+
 // ---------------------------------------------------------------------
 // Section: Static Variables
 // ---------------------------------------------------------------------

src/main/java/world/bentobox/biomes/managers/BiomesAddonManager.java

@@ -27,6 +27,7 @@
 import world.bentobox.bentobox.api.user.User;
 import world.bentobox.bentobox.database.Database;
 import world.bentobox.bentobox.database.objects.Island;
+import world.bentobox.bentobox.managers.IslandWorldManager;
 import world.bentobox.bentobox.util.Util;
 import world.bentobox.biomes.BiomesAddon;
 import world.bentobox.biomes.database.objects.BiomesBundleObject;
@@ -1517,6 +1518,42 @@ public boolean hasPriceSet(BiomesObject biomesObject)
     }
 
 
+    // ---------------------------------------------------------------------
+    // Section: Queue methods
+    // ---------------------------------------------------------------------
+
+
+    /**
+     * This method clears biome change queue for the given world.
+     * @param user User who triggers queue cleaning.
+     * @param world World where queue must be cleared.
+     */
+    public void clearQueues(User user, World world)
+    {
+        IslandWorldManager islandWorldManager = this.addon.getPlugin().getIWM();
+        Optional<GameModeAddon> gameMode = islandWorldManager.getAddon(world);
+
+        gameMode.ifPresent(gamemode -> {
+            // Remove all tasks with the same world as given from the queue.
+            this.addon.getUpdateQueue().getProcessQueue().removeIf(task -> gamemode.getOverWorld() == task.getWorld());
+
+            if (islandWorldManager.isNetherGenerate(world) && islandWorldManager.isNetherIslands(world))
+            {
+                this.addon.getUpdateQueue().getProcessQueue().removeIf(task -> gamemode.getNetherWorld() == task.getWorld());
+            }
+
+            if (islandWorldManager.isEndGenerate(world) && islandWorldManager.isEndIslands(world))
+            {
+                this.addon.getUpdateQueue().getProcessQueue().removeIf(task -> gamemode.getEndWorld() == task.getWorld());
+            }
+
+            Utils.sendMessage(user,
+                user.getTranslationOrNothing(Constants.MESSAGES + "queue.clear",
+                    Constants.PARAMETER_GAMEMODE, gamemode.getDescription().getName()));
+        });
+    }
+
+
     // ---------------------------------------------------------------------
     // Section: Variables
     // ---------------------------------------------------------------------

src/main/java/world/bentobox/biomes/tasks/BiomeUpdateTask.java

@@ -305,6 +305,17 @@ public void setWorld(World world)
     }
 
 
+    /**
+     * Gets world.
+     *
+     * @return the world
+     */
+    public World getWorld()
+    {
+        return this.world;
+    }
+
+
     /**
      * Sets min coordinate.
      *

src/main/resources/locales/en-US.yml

@@ -16,6 +16,8 @@ biomes:
       unlock:
         description: "unlocks biome for the player without checks. Adding `true` at the end will mark it as purchased."
         parameters: "<player> <biome-id> [true]"
+      clear-queue:
+        description: "clears biome update queue"
     # This section contains only player commands translations.
     player:
       main:
@@ -864,6 +866,7 @@ biomes:
     migrate-finish: "&a Migration to new data format completed."
     migrate-valid: "&a All data is valid. Migration is not necessary."
     bundle-loaded: "&a Bundle &r [bundle] &a is loaded."
+    clear-queue: "&a Biome change task queue for [gamemode] is cleared."
   errors:
     # Message that is displayed if requested user or island does not have any valid data.
     no-island-data: "&c Island does not have any stored data."