/*
 * Copyright 2013 The Apache Software Foundation.
 *
 * Licensed 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 org.apache.commons.collections4.iterators;

import java.util.Iterator;
import java.util.NoSuchElementException;

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * An {@link Iterator} over a {@link NodeList}.
 * 

* This iterator does not support {@link #remove()} as a {@link NodeList} does not support * removal of items. * * @since 4.0 * @version $Id$ * @see NodeList */ public class NodeListIterator implements Iterator { /** the original NodeList instance */ private final NodeList nodeList; /** The current iterator index */ private int index = 0; /** * Convenience constructor, which creates a new NodeListIterator from * the specified node's childNodes. * * @param node Node, who's child nodes are wrapped by this class. Must not be null * @throws NullPointerException if node is null */ public NodeListIterator(final Node node) { if (node == null) { throw new NullPointerException("Node must not be null."); } this.nodeList = node.getChildNodes(); } /** * Constructor, that creates a new NodeListIterator from the specified * org.w3c.NodeList * * @param nodeList node list, which is wrapped by this class. Must not be null * @throws NullPointerException if nodeList is null */ public NodeListIterator(final NodeList nodeList) { if (nodeList == null) { throw new NullPointerException("NodeList must not be null."); } this.nodeList = nodeList; } public boolean hasNext() { return nodeList == null ? false : index < nodeList.getLength(); } public Node next() { if (nodeList != null && index < nodeList.getLength()) { return nodeList.item(index++); } throw new NoSuchElementException("underlying nodeList has no more elements"); } /** * Throws {@link UnsupportedOperationException}. * * @throws UnsupportedOperationException always */ public void remove() { throw new UnsupportedOperationException("remove() method not supported for a NodeListIterator."); } }