Added World Load/Unload Event listeners to support Forge.

* Added extra check to WorldManager.doLoad to check parent folder when
loading worlds. This is required by Forge since the world container is not
MC root but the overworld root.

src/main/java/com/onarandombox/MultiverseCore/MultiverseCore.java

@@ -73,6 +73,7 @@ import com.onarandombox.MultiverseCore.listeners.MVPlayerListener;
 import com.onarandombox.MultiverseCore.listeners.MVPluginListener;
 import com.onarandombox.MultiverseCore.listeners.MVPortalListener;
 import com.onarandombox.MultiverseCore.listeners.MVWeatherListener;
+import com.onarandombox.MultiverseCore.listeners.MVWorldListener;
 import com.onarandombox.MultiverseCore.utils.AnchorManager;
 import com.onarandombox.MultiverseCore.utils.MVMessaging;
 import com.onarandombox.MultiverseCore.utils.MVPermissions;
@@ -204,6 +205,7 @@ public class MultiverseCore extends JavaPlugin implements MVPlugin, Core {
     private final MVPluginListener pluginListener = new MVPluginListener(this);
     private final MVWeatherListener weatherListener = new MVWeatherListener(this);
     private final MVPortalListener portalListener = new MVPortalListener(this);
+    private final MVWorldListener worldListener = new MVWorldListener(this);
     private MVChatListener chatListener;
 
     // HashMap to contain information relating to the Players.
@@ -459,6 +461,7 @@ public class MultiverseCore extends JavaPlugin implements MVPlugin, Core {
         pm.registerEvents(this.pluginListener, this);
         pm.registerEvents(this.weatherListener, this);
         pm.registerEvents(this.portalListener, this);
+        pm.registerEvents(this.worldListener, this);
         pm.registerEvents(new MVMapListener(this), this);
     }
 

src/main/java/com/onarandombox/MultiverseCore/api/MVWorldManager.java

@@ -109,6 +109,15 @@ public interface MVWorldManager {
      */
     boolean unloadWorld(String name);
 
+    /**
+     * Unload a world from Multiverse with option to prevent calling unloadWorld in Bukkit.
+     *
+     * @param name Name of the world to unload
+     * @param unloadBukkit True if Bukkit world should be unloaded
+     * @return True if the world was unloaded, false if not.
+     */
+    boolean unloadWorld(String name, boolean unloadBukkit);
+
     /**
      * Loads the world. Only use this if the world has been
      * unloaded with {@link #unloadWorld(String)}.

src/main/java/com/onarandombox/MultiverseCore/listeners/MVWorldListener.java

@@ -0,0 +1,60 @@
+/******************************************************************************
+ * Multiverse 2 Copyright (c) the Multiverse Team 2011.                       *
+ * Multiverse 2 is licensed under the BSD License.                            *
+ * For more information please check the README.md file included              *
+ * with this project.                                                         *
+ ******************************************************************************/
+
+package com.onarandombox.MultiverseCore.listeners;
+
+import com.onarandombox.MultiverseCore.MultiverseCore;
+import com.onarandombox.MultiverseCore.api.MVWorldManager;
+import org.bukkit.World;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.world.WorldLoadEvent;
+import org.bukkit.event.world.WorldUnloadEvent;
+
+/**
+ * Multiverse's World {@link Listener}.
+ */
+public class MVWorldListener implements Listener {
+    private MultiverseCore plugin;
+    private MVWorldManager worldManager;
+
+    public MVWorldListener(MultiverseCore plugin) {
+        this.plugin = plugin;
+        this.worldManager = plugin.getMVWorldManager();
+    }
+
+    /**
+     * This method is called when Bukkit fires off a WorldUnloadEvent.
+     * @param event The Event that was fired.
+     */
+    @EventHandler
+    public void unloadWorld(WorldUnloadEvent event) {
+        if (event.isCancelled()) {
+            return;
+        }
+        if (event.getWorld() instanceof World) {
+            World world = (World) event.getWorld();
+            if (world != null) {
+                this.plugin.getMVWorldManager().unloadWorld(world.getName(), false);
+            }
+        }
+    }
+
+    /**
+     * This method is called when Bukkit fires off a WorldLoadEvent.
+     * @param event The Event that was fired.
+     */
+    @EventHandler
+    public void loadWorld(WorldLoadEvent event) {
+        if (event.getWorld() instanceof World) {
+            World world = (World) event.getWorld();
+            if (world != null && this.plugin.getMVWorldManager().getUnloadedWorlds().contains(world.getName())) {
+                this.plugin.getMVWorldManager().loadWorld(world.getName());
+            }
+        }
+    }
+}

src/main/java/com/onarandombox/MultiverseCore/utils/WorldManager.java

@@ -316,9 +316,21 @@ public class WorldManager implements MVWorldManager {
      */
     @Override
     public boolean unloadWorld(String name) {
+        return this.unloadWorld(name, true);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean unloadWorld(String name, boolean unloadBukkit) {
         if (this.worlds.containsKey(name)) {
             this.worldsFromTheConfig.get(name).cacheVirtualProperties();
-            if (this.unloadWorldFromBukkit(name, true)) {
+            if (unloadBukkit && this.unloadWorldFromBukkit(name, true)) {
+                this.worlds.remove(name);
+                Logging.info("World '%s' was unloaded from memory.", name);
+                return true;
+            } else if (!unloadBukkit){
                 this.worlds.remove(name);
                 Logging.info("World '%s' was unloaded from memory.", name);
                 return true;
@@ -397,7 +409,7 @@ public class WorldManager implements MVWorldManager {
         if (worlds.containsKey(worldName))
             throw new IllegalArgumentException("That world is already loaded!");
 
-        if (!ignoreExists && !new File(this.plugin.getServer().getWorldContainer(), worldName).exists()) {
+        if (!ignoreExists && !new File(this.plugin.getServer().getWorldContainer(), worldName).exists() && !new File(this.plugin.getServer().getWorldContainer().getParent(), worldName).exists()) {
             this.plugin.log(Level.WARNING, "WorldManager: Can't load this world because the folder was deleted/moved: " + worldName);
             this.plugin.log(Level.WARNING, "Use '/mv remove' to remove it from the config!");
             return false;