001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.collections.iterators;
018
019 import java.util.Enumeration;
020 import java.util.Iterator;
021
022 /**
023 * Adapter to make an {@link Iterator Iterator} instance appear to be
024 * an {@link Enumeration Enumeration} instance.
025 *
026 * @since Commons Collections 1.0
027 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
028 *
029 * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
030 */
031 public class IteratorEnumeration implements Enumeration {
032
033 /** The iterator being decorated. */
034 private Iterator iterator;
035
036 /**
037 * Constructs a new <code>IteratorEnumeration</code> that will not
038 * function until {@link #setIterator(Iterator) setIterator} is
039 * invoked.
040 */
041 public IteratorEnumeration() {
042 super();
043 }
044
045 /**
046 * Constructs a new <code>IteratorEnumeration</code> that will use
047 * the given iterator.
048 *
049 * @param iterator the iterator to use
050 */
051 public IteratorEnumeration( Iterator iterator ) {
052 super();
053 this.iterator = iterator;
054 }
055
056 // Iterator interface
057 //-------------------------------------------------------------------------
058
059 /**
060 * Returns true if the underlying iterator has more elements.
061 *
062 * @return true if the underlying iterator has more elements
063 */
064 public boolean hasMoreElements() {
065 return iterator.hasNext();
066 }
067
068 /**
069 * Returns the next element from the underlying iterator.
070 *
071 * @return the next element from the underlying iterator.
072 * @throws java.util.NoSuchElementException if the underlying iterator has no
073 * more elements
074 */
075 public Object nextElement() {
076 return iterator.next();
077 }
078
079 // Properties
080 //-------------------------------------------------------------------------
081
082 /**
083 * Returns the underlying iterator.
084 *
085 * @return the underlying iterator
086 */
087 public Iterator getIterator() {
088 return iterator;
089 }
090
091 /**
092 * Sets the underlying iterator.
093 *
094 * @param iterator the new underlying iterator
095 */
096 public void setIterator( Iterator iterator ) {
097 this.iterator = iterator;
098 }
099
100 }