l2j-server-game/java/com/l2jserver/util/EmptyQueue.java

/*
 * Copyright (C) 2004-2015 L2J Server
 * 
 * This file is part of L2J Server.
 * 
 * L2J Server 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.
 * 
 * L2J Server 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.l2jserver.util;

import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.Queue;

/**
 * @author UnAfraid
 * @param <E>
 */
public final class EmptyQueue<E> implements Queue<E>
{
	private static final Queue<Object> EMPTY_QUEUE = new EmptyQueue<>();
	
	@SuppressWarnings("unchecked")
	public static <E> Queue<E> emptyQueue()
	{
		return (Queue<E>) EMPTY_QUEUE;
	}
	
	@Override
	public int size()
	{
		return 0;
	}
	
	@Override
	public boolean isEmpty()
	{
		return true;
	}
	
	@Override
	public boolean contains(Object o)
	{
		return false;
	}
	
	@Override
	public Iterator<E> iterator()
	{
		return Collections.<E> emptyIterator();
	}
	
	@Override
	public Object[] toArray()
	{
		return new Object[0];
	}
	
	@Override
	public <T> T[] toArray(T[] a)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean remove(Object o)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean containsAll(Collection<?> c)
	{
		return false;
	}
	
	@Override
	public boolean addAll(Collection<? extends E> c)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean removeAll(Collection<?> c)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean retainAll(Collection<?> c)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public void clear()
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean add(E e)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public boolean offer(E e)
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public E remove()
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public E poll()
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public E element()
	{
		throw new UnsupportedOperationException();
	}
	
	@Override
	public E peek()
	{
		throw new UnsupportedOperationException();
	}
}