[Bleeding] Changed event system into a new, much faster design. Huge thanks to @zml2008 & @lahwran.

src/main/java/org/bukkit/event/world/ChunkEvent.java

@@ -6,7 +6,7 @@ import org.bukkit.Chunk;
  * Represents a Chunk related event
  */
 @SuppressWarnings("serial")
-public class ChunkEvent extends WorldEvent {
+public abstract class ChunkEvent extends WorldEvent {
     protected Chunk chunk;
 
     protected ChunkEvent(Type type, Chunk chunk) {

src/main/java/org/bukkit/event/world/ChunkLoadEvent.java

@@ -1,12 +1,14 @@
 package org.bukkit.event.world;
 
 import org.bukkit.Chunk;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a chunk is loaded
  */
 @SuppressWarnings("serial")
 public class ChunkLoadEvent extends ChunkEvent {
+    private static final HandlerList handlers = new HandlerList();
     private final boolean newChunk;
 
     public ChunkLoadEvent(final Chunk chunk, final boolean newChunk) {
@@ -23,4 +25,13 @@ public class ChunkLoadEvent extends ChunkEvent {
     public boolean isNewChunk() {
         return newChunk;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/ChunkPopulateEvent.java

@@ -1,6 +1,7 @@
 package org.bukkit.event.world;
 
 import org.bukkit.Chunk;
+import org.bukkit.event.HandlerList;
 import org.bukkit.generator.BlockPopulator;
 
 /**
@@ -10,7 +11,17 @@ import org.bukkit.generator.BlockPopulator;
  */
 @SuppressWarnings("serial")
 public class ChunkPopulateEvent extends ChunkEvent {
+    private static final HandlerList handlers = new HandlerList();
     public ChunkPopulateEvent(final Chunk chunk) {
         super(Type.CHUNK_POPULATED, chunk);
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/ChunkUnloadEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.world;
 
 import org.bukkit.Chunk;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a chunk is unloaded
  */
 @SuppressWarnings("serial")
 public class ChunkUnloadEvent extends ChunkEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel = false;
 
     public ChunkUnloadEvent(final Chunk chunk) {
@@ -21,4 +23,13 @@ public class ChunkUnloadEvent extends ChunkEvent implements Cancellable {
     public void setCancelled(boolean cancel) {
         this.cancel = cancel;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/PortalCreateEvent.java

@@ -3,6 +3,8 @@ package org.bukkit.event.world;
 import org.bukkit.block.Block;
 import org.bukkit.World;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+
 import java.util.ArrayList;
 import java.util.Collection;
 
@@ -11,6 +13,7 @@ import java.util.Collection;
  */
 @SuppressWarnings("serial")
 public class PortalCreateEvent extends WorldEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel = false;
     private ArrayList<Block> blocks = new ArrayList<Block>();
 
@@ -35,4 +38,13 @@ public class PortalCreateEvent extends WorldEvent implements Cancellable {
     public void setCancelled(boolean cancel) {
         this.cancel = cancel;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/SpawnChangeEvent.java

@@ -2,6 +2,7 @@ package org.bukkit.event.world;
 
 import org.bukkit.World;
 import org.bukkit.Location;
+import org.bukkit.event.HandlerList;
 
 /**
  * An event that is called when a world's spawn changes. The
@@ -9,6 +10,7 @@ import org.bukkit.Location;
  */
 @SuppressWarnings("serial")
 public class SpawnChangeEvent extends WorldEvent {
+    private static final HandlerList handlers = new HandlerList();
     private Location previousLocation;
 
     public SpawnChangeEvent(World world, Location previousLocation) {
@@ -24,4 +26,13 @@ public class SpawnChangeEvent extends WorldEvent {
     public Location getPreviousLocation() {
         return previousLocation;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/StructureGrowEvent.java

@@ -6,11 +6,13 @@ import org.bukkit.TreeType;
 import org.bukkit.block.BlockState;
 import org.bukkit.entity.Player;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Event that is called when an organic structure attempts to grow (Sapling -> Tree), (Mushroom -> Huge Mushroom), naturally or using bonemeal.
  */
 public class StructureGrowEvent extends WorldEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private static final long serialVersionUID = 1L;
     private boolean cancelled = false;
     private Location location;
@@ -80,4 +82,13 @@ public class StructureGrowEvent extends WorldEvent implements Cancellable {
     public void setCancelled(boolean cancel) {
         cancelled = cancel;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/WorldEvent.java

@@ -7,7 +7,7 @@ import org.bukkit.event.Event;
  * Represents events within a world
  */
 @SuppressWarnings("serial")
-public class WorldEvent extends Event {
+public abstract class WorldEvent extends Event {
     private final World world;
 
     public WorldEvent(final Type type, final World world) {

src/main/java/org/bukkit/event/world/WorldInitEvent.java

@@ -1,13 +1,24 @@
 package org.bukkit.event.world;
 
 import org.bukkit.World;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a World is initializing
  */
 @SuppressWarnings("serial")
 public class WorldInitEvent extends WorldEvent {
+    private static final HandlerList handlers = new HandlerList();
     public WorldInitEvent(World world) {
         super(Type.WORLD_INIT, world);
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/WorldListener.java

@@ -5,6 +5,7 @@ import org.bukkit.event.Listener;
 /**
  * Handles all World related events
  */
+@Deprecated
 public class WorldListener implements Listener {
 
     /**

src/main/java/org/bukkit/event/world/WorldLoadEvent.java

@@ -1,13 +1,24 @@
 package org.bukkit.event.world;
 
 import org.bukkit.World;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a World is loaded
  */
 @SuppressWarnings("serial")
 public class WorldLoadEvent extends WorldEvent {
+    private static final HandlerList handlers = new HandlerList();
     public WorldLoadEvent(World world) {
         super(Type.WORLD_LOAD, world);
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/WorldSaveEvent.java

@@ -1,10 +1,21 @@
 package org.bukkit.event.world;
 
 import org.bukkit.World;
+import org.bukkit.event.HandlerList;
 
 @SuppressWarnings("serial")
 public class WorldSaveEvent extends WorldEvent {
+    private static final HandlerList handlers = new HandlerList();
     public WorldSaveEvent(World world) {
         super(Type.WORLD_SAVE, world);
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/world/WorldUnloadEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.world;
 
 import org.bukkit.World;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a World is unloaded
  */
 @SuppressWarnings("serial")
 public class WorldUnloadEvent extends WorldEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean isCancelled;
 
     public WorldUnloadEvent(World world) {
@@ -21,4 +23,13 @@ public class WorldUnloadEvent extends WorldEvent implements Cancellable {
     public void setCancelled(boolean cancel) {
         this.isCancelled = cancel;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }