Simplify implementation of preventing axolotl damage

Author: Akiranya

src/com/palmergames/bukkit/towny/listeners/TownyEntityListener.java

@@ -43,14 +43,6 @@
  * 
  */
 public class TownyEntityListener implements Listener {
-
-	/**
-	 * A Map that stores the target of Axolotls which has ever been cancelled
-	 * attack damage by Towny, where key is {@link Fish} (defender) and value is
-	 * a set of {@link Axolotl} (attacker).
-	 */
-	public static final Map<Entity, Set<Entity>> axolotlTargetExempt = new WeakHashMap<>();
-
 	private final Towny plugin;
 
 	public TownyEntityListener(Towny instance) {
@@ -127,21 +119,17 @@ public void onEntityDamageByEntity(EntityDamageByEntityEvent event) {
 	}
 
 	/**
-	 * Prevent axolotl from targeting protected mobs if Towny has ever cancelled
-	 * the damage previously. Note that axolotls would still make the first attack
-	 * due to this listener relies on the states produced in {@link
-	 * CombatUtil#preventDamageCall(Entity, Entity, DamageCause)}.
+	 * Prevent axolotl from targeting protected mobs.
 	 *
 	 * @param event - EntityTargetLivingEntityEvent
 	 */
 	@EventHandler(priority = EventPriority.LOWEST, ignoreCancelled = true)
 	public void onAxolotlTarget(EntityTargetLivingEntityEvent event) {
-		var attacker = event.getEntity();
-		var defender = event.getTarget();
-		if (attacker.getType() == EntityType.AXOLOTL && axolotlTargetExempt.containsKey(defender) && axolotlTargetExempt.get(defender).contains(attacker)) {
-			event.setTarget(null);
-			event.setCancelled(true);
-			((Axolotl) attacker).setMemory(MemoryKey.HAS_HUNTING_COOLDOWN, true);
+		if (event.getEntity() instanceof Axolotl axolotl && 
+			event.getTarget() instanceof Mob target && 
+			CombatUtil.preventDamageCall(axolotl, target, DamageCause.ENTITY_ATTACK)) {
+			axolotl.setTarget(null);
+			axolotl.setMemory(MemoryKey.HAS_HUNTING_COOLDOWN, true);
 		}
 	}
 

src/com/palmergames/bukkit/towny/utils/CombatUtil.java

@@ -3,22 +3,19 @@
 import com.palmergames.bukkit.towny.*;
 import com.palmergames.bukkit.towny.event.damage.*;
 import com.palmergames.bukkit.towny.event.executors.TownyActionEventExecutor;
-import com.palmergames.bukkit.towny.listeners.TownyEntityListener;
 import com.palmergames.bukkit.towny.object.*;
 import com.palmergames.bukkit.towny.object.TownyPermission.ActionType;
 import com.palmergames.bukkit.util.BukkitTools;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.block.Block;
 import org.bukkit.entity.*;
+import org.bukkit.entity.memory.MemoryKey;
 import org.bukkit.event.entity.EntityDamageEvent.DamageCause;
 import org.bukkit.projectiles.BlockProjectileSource;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.Collections;
-import java.util.List;
-import java.util.Set;
-import java.util.WeakHashMap;
+import java.util.*;
 
 /**
  * 
@@ -275,20 +272,11 @@ private static boolean preventDamageCall(TownyWorld world, Entity attackingEntit
 				}
 
 				/*
-				 * Actually "clear" axolotl's target.
-				 * See TownyEntityListener#onAxolotlTarget for more information.
-				 * This also makes it possible to make a nice fish tank where
-				 * the axolotls won't have attack behaviours on other fish
-				 * if Fish is specified in the protection.mob_types list.
+				 * Clear axolotl's target.
 				 * */
-				if (attackingEntity.getType() == EntityType.AXOLOTL && EntityTypeUtil.isInstanceOfAny(TownySettings.getProtectedEntityTypes(), defendingEntity)) {
-					if (TownyEntityListener.axolotlTargetExempt.containsKey(defendingEntity)) {
-						TownyEntityListener.axolotlTargetExempt.get(defendingEntity).add(attackingEntity);
-					} else {
-						Set<Entity> axolotlSet = Collections.newSetFromMap(new WeakHashMap<>()); // axolotl attackers
-						axolotlSet.add(attackingEntity);
-						TownyEntityListener.axolotlTargetExempt.put(defendingEntity, axolotlSet);
-					}
+				if (attackingEntity instanceof Axolotl axolotl && EntityTypeUtil.isInstanceOfAny(TownySettings.getProtectedEntityTypes(), defendingEntity)) {
+					axolotl.setTarget(null);
+					axolotl.setMemory(MemoryKey.HAS_HUNTING_COOLDOWN, true);
 					return true;
 				}
 			}