plugins/org.eclipse.viatra2.core2/src/org/eclipse/viatra2/core/simple/OneIterator.java

/*******************************************************************************
 * Copyright (c) 2004-2008 Andras Schmidt, Andras Balogh, Istvan Rath and Daniel Varro
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Andras Schmidt, Andras Balogh, Istvan Rath - initial API and implementation
 *******************************************************************************/

package org.eclipse.viatra2.core.simple;

import java.util.Iterator;

/**
 * Iterator of a singleton or an empty collection
 * 
 * @author Andras Schmidt
 * 
 */
public class OneIterator<T> implements Iterator<T> {
	T o;

	/**
	 * Instantiate a iterator of a singleton or an empty collection
	 * 
	 * @param o
	 *            null: singleton colection, not null: collection that contains
	 *            the given object
	 */
	public OneIterator(T o) {
		this.o = o;
	}

	public boolean hasNext() {
		return o != null;
	}

	public T next() {
		T ret = o;
		o = null;
		return ret;
	}

	public void remove() {
	}
}