Merged with released L2J-Unity files.

trunk/java/com/l2jmobius/gameserver/model/CreatureContainer.java

@@ -0,0 +1,106 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jmobius.gameserver.model;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ScheduledFuture;
+import java.util.function.Predicate;
+
+import com.l2jmobius.gameserver.ThreadPoolManager;
+import com.l2jmobius.gameserver.model.actor.L2Character;
+import com.l2jmobius.gameserver.model.events.EventDispatcher;
+import com.l2jmobius.gameserver.model.events.impl.character.OnCreatureSee;
+
+/**
+ * @author UnAfraid
+ */
+public class CreatureContainer
+{
+	private final Set<Integer> _seen = ConcurrentHashMap.newKeySet();
+	private final L2Character _owner;
+	private final int _range;
+	private ScheduledFuture<?> _task;
+	private Predicate<L2Character> _condition = null;
+	
+	public CreatureContainer(L2Character owner, int range, Predicate<L2Character> condition)
+	{
+		_owner = owner;
+		_range = range;
+		_condition = condition;
+		start();
+	}
+	
+	public L2Character getOwner()
+	{
+		return _owner;
+	}
+	
+	public int getRange()
+	{
+		return _range;
+	}
+	
+	/**
+	 * Starts the task that scans for new creatures
+	 */
+	public void start()
+	{
+		if ((_task == null) || _task.isDone())
+		{
+			_task = ThreadPoolManager.getInstance().scheduleAiAtFixedRate(this::update, 1000L, 1000L);
+		}
+	}
+	
+	/**
+	 * @return {@code false} if the task could not be cancelled, typically because it has already completed normally; {@code true} otherwise
+	 */
+	public boolean stop()
+	{
+		return (_task != null) && !_task.isDone() && _task.cancel(false);
+	}
+	
+	/**
+	 * Resets the creatures container, all previously seen creature will be discarded and next time update method is called will notify for each creature that owner sees!
+	 */
+	public void reset()
+	{
+		_seen.clear();
+	}
+	
+	/**
+	 * Scans around the npc and notifies about new creature owner seen
+	 */
+	private void update()
+	{
+		final Set<Integer> verified = new HashSet<>();
+		L2World.getInstance().forEachVisibleObjectInRange(_owner, L2Character.class, _range, creature ->
+		{
+			if ((_condition == null) || _condition.test(creature))
+			{
+				if (_seen.add(creature.getObjectId()))
+				{
+					EventDispatcher.getInstance().notifyEventAsync(new OnCreatureSee(_owner, creature), _owner);
+				}
+				verified.add(creature.getObjectId());
+			}
+		});
+		
+		_seen.retainAll(verified);
+	}
+}