/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package java.util;


/**
 * An Iterator is used to sequence over a collection of objects.
 */
public interface Iterator<E> {
	/**
	 * Answers if there are more elements to iterate.
	 * 
	 * @return true if there are more elements, false otherwise
	 * 
	 * @see #next
	 */
	public boolean hasNext();

	/**
	 * Answers the next object in the iteration.
	 * 
	 * @return the next object
	 * 
	 * @exception NoSuchElementException
	 *                when there are no more elements
	 * 
	 * @see #hasNext
	 */
	public E next();

	/**
	 * Removes the last object returned by <code>next</code> from the
	 * collection.
	 * 
	 * @exception UnsupportedOperationException
	 *                when removing is not supported by the collection being
	 *                iterated
	 * @exception IllegalStateException
	 *                when <code>next</code> has not been called, or
	 *                <code>remove</code> has already been called after the
	 *                last call to <code>next</code>
	 */
	public void remove();
}
