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

src/main/java/org/bukkit/event/entity/CreatureSpawnEvent.java

@@ -4,6 +4,7 @@ import org.bukkit.entity.CreatureType;
 import org.bukkit.entity.Entity;
 import org.bukkit.Location;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a creature is spawned into a world.
@@ -12,6 +13,7 @@ import org.bukkit.event.Cancellable;
  */
 @SuppressWarnings("serial")
 public class CreatureSpawnEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private Location location;
     private boolean canceled;
@@ -60,6 +62,15 @@ public class CreatureSpawnEvent extends EntityEvent implements Cancellable {
         return spawnReason;
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
     /**
      * An enum to specify the type of spawning
      */

src/main/java/org/bukkit/event/entity/CreeperPowerEvent.java

@@ -2,6 +2,7 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a Creeper is struck by lightning.
@@ -10,6 +11,7 @@ import org.bukkit.event.Cancellable;
  */
 @SuppressWarnings("serial")
 public class CreeperPowerEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private boolean canceled;
     private PowerCause cause;
@@ -53,6 +55,15 @@ public class CreeperPowerEvent extends EntityEvent implements Cancellable {
         return cause;
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
     /**
      * An enum to specify the cause of the change in power
      */

src/main/java/org/bukkit/event/entity/EndermanPickupEvent.java

@@ -3,9 +3,11 @@ package org.bukkit.event.entity;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 @SuppressWarnings("serial")
 public class EndermanPickupEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private boolean cancel;
     private Block block;
@@ -32,4 +34,13 @@ public class EndermanPickupEvent extends EntityEvent implements Cancellable {
     public Block getBlock() {
         return block;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EndermanPlaceEvent.java

@@ -3,9 +3,11 @@ package org.bukkit.event.entity;
 import org.bukkit.Location;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 @SuppressWarnings("serial")
 public class EndermanPlaceEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private boolean cancel;
     private Location location;
@@ -32,4 +34,13 @@ public class EndermanPlaceEvent extends EntityEvent implements Cancellable {
     public Location getLocation() {
         return location;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityCombustEvent.java

@@ -2,6 +2,7 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when an entity combusts.
@@ -10,6 +11,7 @@ import org.bukkit.event.Cancellable;
  */
 @SuppressWarnings("serial")
 public class EntityCombustEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private int duration;
     private boolean cancel;
 
@@ -44,4 +46,13 @@ public class EntityCombustEvent extends EntityEvent implements Cancellable {
     public void setDuration(int duration) {
         this.duration = duration;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityCreatePortalEvent.java

@@ -5,11 +5,13 @@ import org.bukkit.PortalType;
 import org.bukkit.block.BlockState;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Thrown when a Living Entity creates a portal in a world.
  */
 public class EntityCreatePortalEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private List<BlockState> blocks;
     private boolean cancelled = false;
     private PortalType type = PortalType.CUSTOM;
@@ -46,4 +48,13 @@ public class EntityCreatePortalEvent extends EntityEvent implements Cancellable
     public PortalType getPortalType() {
         return type;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityDamageEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
 import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
 
 /**
  * Stores data for damage events
  */
 @SuppressWarnings("serial")
 public class EntityDamageEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private int damage;
     private boolean cancelled;
@@ -61,6 +63,15 @@ public class EntityDamageEvent extends EntityEvent implements Cancellable {
         return cause;
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
     /**
      * An enum to specify the cause of the damage
      */

src/main/java/org/bukkit/event/entity/EntityDeathEvent.java

@@ -2,6 +2,7 @@ package org.bukkit.event.entity;
 
 import java.util.List;
 import org.bukkit.entity.Entity;
+import org.bukkit.event.HandlerList;
 import org.bukkit.inventory.ItemStack;
 
 /**
@@ -9,6 +10,7 @@ import org.bukkit.inventory.ItemStack;
  */
 @SuppressWarnings("serial")
 public class EntityDeathEvent extends EntityEvent {
+    private static final HandlerList handlers = new HandlerList();
     private List<ItemStack> drops;
     private int dropExp = 0;
 
@@ -54,4 +56,13 @@ public class EntityDeathEvent extends EntityEvent {
     public List<ItemStack> getDrops() {
         return drops;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityEvent.java

@@ -7,7 +7,7 @@ import org.bukkit.event.Event;
  * Represents an Entity-related event
  */
 @SuppressWarnings("serial")
-public class EntityEvent extends Event {
+public abstract class EntityEvent extends Event {
     protected Entity entity;
 
     public EntityEvent(final Event.Type type, final Entity what) {

src/main/java/org/bukkit/event/entity/EntityExplodeEvent.java

@@ -4,6 +4,7 @@ import org.bukkit.Location;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 import java.util.List;
 
@@ -12,6 +13,7 @@ import java.util.List;
  */
 @SuppressWarnings("serial")
 public class EntityExplodeEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel;
     private Location location;
     private List<Block> blocks;
@@ -76,4 +78,13 @@ public class EntityExplodeEvent extends EntityEvent implements Cancellable {
     public void setYield(float yield) {
         this.yield = yield;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityInteractEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when an entity interacts with an object
  */
 @SuppressWarnings("serial")
 public class EntityInteractEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     protected Block block;
 
     private boolean cancelled;
@@ -34,4 +36,13 @@ public class EntityInteractEvent extends EntityEvent implements Cancellable {
     public Block getBlock() {
         return block;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityListener.java

@@ -7,6 +7,7 @@ import org.bukkit.event.painting.PaintingBreakEvent;
 /**
  * Handles all events fired in relation to entities
  */
+@Deprecated
 public class EntityListener implements Listener {
     public EntityListener() {}
 

src/main/java/org/bukkit/event/entity/EntityPortalEnterEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.Location;
+import org.bukkit.event.HandlerList;
 
 /**
  * Stores data for entities standing inside a portal block
  */
 @SuppressWarnings("serial")
 public class EntityPortalEnterEvent extends EntityEvent {
+    private static final HandlerList handlers = new HandlerList();
 
     private Location location;
 
@@ -24,4 +26,13 @@ public class EntityPortalEnterEvent extends EntityEvent {
     public Location getLocation() {
         return location;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityRegainHealthEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
 import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
 
 /**
  * Stores data for health-regain events
  */
 @SuppressWarnings("serial")
 public class EntityRegainHealthEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private boolean cancelled;
     private int amount;
@@ -55,6 +57,15 @@ public class EntityRegainHealthEvent extends EntityEvent implements Cancellable
         return regainReason;
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
     /**
      * An enum to specify the type of health regaining that is occurring
      */

src/main/java/org/bukkit/event/entity/EntityTameEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.entity.AnimalTamer;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Thrown when a LivingEntity is tamed
  */
 @SuppressWarnings("serial")
 public class EntityTameEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancelled;
     private AnimalTamer owner;
 
@@ -33,4 +35,13 @@ public class EntityTameEvent extends EntityEvent implements Cancellable {
     public AnimalTamer getOwner() {
         return owner;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/EntityTargetEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a creature targets or untargets another entity
  */
 @SuppressWarnings("serial")
 public class EntityTargetEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel;
     private Entity target;
     private TargetReason reason;
@@ -62,6 +64,15 @@ public class EntityTargetEvent extends EntityEvent implements Cancellable {
         this.target = target;
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
     /**
      * An enum to specify the reason for the targeting
      */

src/main/java/org/bukkit/event/entity/ExplosionPrimeEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Explosive;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when an entity has made a decision to explode.
  */
 @SuppressWarnings("serial")
 public class ExplosionPrimeEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel;
     private float radius;
     private boolean fire;
@@ -67,4 +69,13 @@ public class ExplosionPrimeEvent extends EntityEvent implements Cancellable {
     public void setFire(boolean fire) {
         this.fire = fire;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/FoodLevelChangeEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a human entity's food level changes
  */
 @SuppressWarnings("serial")
 public class FoodLevelChangeEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel = false;
     private int level;
 
@@ -46,4 +48,13 @@ public class FoodLevelChangeEvent extends EntityEvent 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/entity/ItemDespawnEvent.java

@@ -3,8 +3,10 @@ package org.bukkit.event.entity;
 import org.bukkit.Location;
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 public class ItemDespawnEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean canceled;
     private Location location;
 
@@ -29,4 +31,13 @@ public class ItemDespawnEvent extends EntityEvent implements Cancellable {
     public Location getLocation() {
         return location;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/ItemSpawnEvent.java

@@ -3,12 +3,14 @@ package org.bukkit.event.entity;
 import org.bukkit.entity.Entity;
 import org.bukkit.Location;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when an item is spawned into a world
  */
 @SuppressWarnings("serial")
 public class ItemSpawnEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private Location location;
     private boolean canceled;
@@ -34,4 +36,13 @@ public class ItemSpawnEvent extends EntityEvent implements Cancellable {
     public Location getLocation() {
         return location;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/PigZapEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Stores data for pigs being zapped
  */
 @SuppressWarnings("serial")
 public class PigZapEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
 
     private boolean canceled;
     private Entity pigzombie;
@@ -45,4 +47,13 @@ public class PigZapEvent extends EntityEvent implements Cancellable {
     public Entity getPigZombie() {
         return pigzombie;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }

src/main/java/org/bukkit/event/entity/ProjectileHitEvent.java

@@ -1,15 +1,26 @@
 package org.bukkit.event.entity;
 
 import org.bukkit.entity.Projectile;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a projectile hits an object
  */
 @SuppressWarnings("serial")
 public class ProjectileHitEvent extends EntityEvent {
+    private static final HandlerList handlers = new HandlerList();
 
     public ProjectileHitEvent(Projectile projectile) {
         super(Type.PROJECTILE_HIT, projectile);
     }
 
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
 }

src/main/java/org/bukkit/event/entity/SlimeSplitEvent.java

@@ -2,12 +2,14 @@ package org.bukkit.event.entity;
 
 import org.bukkit.entity.Entity;
 import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
 
 /**
  * Called when a Slime splits into smaller Slimes upon death
  */
 @SuppressWarnings("serial")
 public class SlimeSplitEvent extends EntityEvent implements Cancellable {
+    private static final HandlerList handlers = new HandlerList();
     private boolean cancel;
     private int count;
 
@@ -42,4 +44,13 @@ public class SlimeSplitEvent extends EntityEvent implements Cancellable {
     public void setCount(int count) {
         this.count = count;
     }
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
 }