Synchronized all access to worlds map in WorldManager.

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

@@ -45,10 +45,10 @@ import java.util.logging.Logger;
  * Public facing API to add/remove Multiverse worlds.
  */
 public class WorldManager implements MVWorldManager {
-    private MultiverseCore plugin;
+    private final MultiverseCore plugin;
-    private WorldPurger worldPurger;
+    private final WorldPurger worldPurger;
+    private final Map<String, MultiverseWorld> worlds;
     private Map<String, MVWorld> worldsFromTheConfig;
-    private Map<String, MultiverseWorld> worlds;
     private FileConfiguration configWorlds = null;
     private Map<String, String> defaultGens;
     private String firstSpawn;
@@ -225,7 +225,9 @@ public class WorldManager implements MVWorldManager {
         }
 
         // set generator (special case because we can't read it from org.bukkit.World)
+        synchronized (worlds) {
             this.worlds.get(name).setGenerator(generator);
+        }
 
         this.saveWorldsConfig();
         return true;
@@ -304,6 +306,7 @@ public class WorldManager implements MVWorldManager {
      */
     @Override
     public boolean unloadWorld(String name) {
+        synchronized (worlds) {
             if (this.worlds.containsKey(name)) {
                 if (this.unloadWorldFromBukkit(name, true)) {
                     this.worlds.remove(name);
@@ -322,6 +325,7 @@ public class WorldManager implements MVWorldManager {
             } else {
                 this.plugin.log(Level.INFO, "Multiverse does not know about " + name + " and it's not loaded by Bukkit.");
             }
+        }
         return false;
     }
 
@@ -331,9 +335,11 @@ public class WorldManager implements MVWorldManager {
     @Override
     public boolean loadWorld(String name) {
         // Check if the World is already loaded
+        synchronized (worlds) {
             if (this.worlds.containsKey(name)) {
                 return true;
             }
+        }
 
         // Check that the world is in the config
         if (worldsFromTheConfig.containsKey(name)) {
@@ -367,8 +373,10 @@ public class WorldManager implements MVWorldManager {
         String worldName = creator.name();
         if (!worldsFromTheConfig.containsKey(worldName))
             throw new IllegalArgumentException("That world doesn't exist!");
+        synchronized (worlds) {
             if (worlds.containsKey(worldName))
                 throw new IllegalArgumentException("That world is already loaded!");
+        }
         MVWorld mvworld = worldsFromTheConfig.get(worldName);
         World cbworld;
         try {
@@ -380,7 +388,9 @@ public class WorldManager implements MVWorldManager {
         }
         mvworld.init(cbworld, plugin);
         this.worldPurger.purgeWorld(mvworld);
+        synchronized (worlds) {
             this.worlds.put(worldName, mvworld);
+        }
         return true;
     }
 
@@ -477,17 +487,21 @@ public class WorldManager implements MVWorldManager {
      */
     @Override
     public Collection<MultiverseWorld> getMVWorlds() {
+        synchronized (worlds) {
             return this.worlds.values();
         }
+    }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public MultiverseWorld getMVWorld(String name) {
+        synchronized (worlds) {
             if (this.worlds.containsKey(name)) {
                 return this.worlds.get(name);
             }
+        }
         return this.getMVWorldByAlias(name);
     }
 
@@ -509,11 +523,13 @@ public class WorldManager implements MVWorldManager {
      * @return A {@link MVWorld} or null.
      */
     private MultiverseWorld getMVWorldByAlias(String alias) {
+        synchronized (worlds) {
             for (MultiverseWorld w : this.worlds.values()) {
                 if (w.getAlias().equalsIgnoreCase(alias)) {
                     return w;
                 }
             }
+        }
         return null;
     }
 
@@ -522,8 +538,10 @@ public class WorldManager implements MVWorldManager {
      */
     @Override
     public boolean isMVWorld(String name) {
+        synchronized (worlds) {
             return (this.worlds.containsKey(name) || isMVWorldAlias(name));
         }
+    }
 
     /**
      * {@inheritDoc}
@@ -540,11 +558,13 @@ public class WorldManager implements MVWorldManager {
      * @return True if the world exists, false if not.
      */
     private boolean isMVWorldAlias(String alias) {
+        synchronized (worlds) {
             for (MultiverseWorld w : this.worlds.values()) {
                 if (w.getAlias().equalsIgnoreCase(alias)) {
                     return true;
                 }
             }
+        }
         return false;
     }
 
@@ -589,6 +609,7 @@ public class WorldManager implements MVWorldManager {
             // Remove all world permissions.
             Permission allAccess = this.plugin.getServer().getPluginManager().getPermission("multiverse.access.*");
             Permission allExempt = this.plugin.getServer().getPluginManager().getPermission("multiverse.exempt.*");
+            synchronized (worlds) {
                 for (MultiverseWorld w : this.worlds.values()) {
                     // Remove this world from the master list
                     if (allAccess != null) {
@@ -602,15 +623,20 @@ public class WorldManager implements MVWorldManager {
                     // Special namespace for gamemodes
                     this.plugin.getServer().getPluginManager().removePermission("mv.bypass.gamemode." + w.getName());
                 }
+            }
             // Recalc the all permission
             this.plugin.getServer().getPluginManager().recalculatePermissionDefaults(allAccess);
             this.plugin.getServer().getPluginManager().recalculatePermissionDefaults(allExempt);
+            synchronized (worlds) {
                 this.worlds.clear();
             }
+        }
 
         for (Map.Entry<String, MVWorld> entry : worldsFromTheConfig.entrySet()) {
+            synchronized (worlds) {
                 if (worlds.containsKey(entry.getKey()))
                     continue;
+            }
             if (!entry.getValue().getAutoLoad())
                 continue;
 
@@ -676,9 +702,11 @@ public class WorldManager implements MVWorldManager {
                 String worldName = key.replaceAll(String.valueOf(SEPARATOR), ".");
                 if (this.worldsFromTheConfig.containsKey(worldName)) {
                     // Object-Recycling :D
+                    synchronized (worlds) {
                         MVWorld oldMVWorld = (MVWorld) this.worlds.get(worldName);
                         oldMVWorld.copyValues((MVWorld) obj);
                         newWorldsFromTheConfig.put(worldName, oldMVWorld);
+                    }
                 } else {
                     // we have to use a new one
                     World cbworld = this.plugin.getServer().getWorld(worldName);
@@ -696,7 +724,9 @@ public class WorldManager implements MVWorldManager {
             }
         }
         this.worldsFromTheConfig = newWorldsFromTheConfig;
+        synchronized (worlds) {
             this.worlds.keySet().retainAll(this.worldsFromTheConfig.keySet());
+        }
         return this.configWorlds;
     }
 
@@ -733,7 +763,9 @@ public class WorldManager implements MVWorldManager {
     @Override
     public List<String> getUnloadedWorlds() {
         List<String> allNames = new ArrayList<String>(this.worldsFromTheConfig.keySet());
+        synchronized (worlds) {
             allNames.removeAll(worlds.keySet());
+        }
         return allNames;
     }