001 /*--------------------------------------------------------------------------+
002 $Id: UnmodifiableListIterator.java 26283 2010-02-18 11:18:57Z juergens $
003 | |
004 | Copyright 2005-2010 Technische Universitaet Muenchen |
005 | |
006 | Licensed under the Apache License, Version 2.0 (the "License"); |
007 | you may not use this file except in compliance with the License. |
008 | You may obtain a copy of the License at |
009 | |
010 | http://www.apache.org/licenses/LICENSE-2.0 |
011 | |
012 | Unless required by applicable law or agreed to in writing, software |
013 | distributed under the License is distributed on an "AS IS" BASIS, |
014 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
015 | See the License for the specific language governing permissions and |
016 | limitations under the License. |
017 +--------------------------------------------------------------------------*/
018 package edu.tum.cs.commons.collections;
019
020 import java.util.ListIterator;
021
022 /**
023 * This is a wrapper for a {@link ListIterator} prohibiting all calls which
024 * would modify its owning container. All prohibited methods throw an
025 * {@link UnsupportedOperationException}.
026 *
027 * @author Benjamin Hummel
028 * @author $Author: juergens $
029 *
030 * @version $Revision: 26283 $
031 * @levd.rating GREEN Hash: 9BFBB340546768A49651FF141F51F985
032 */
033 public class UnmodifiableListIterator<T> extends UnmodifiableIterator<T>
034 implements ListIterator<T> {
035
036 /** The underlying iterator. */
037 private final ListIterator<T> i;
038
039 /**
040 * Creates a new unmodifiable list iterator from another list iterator. All
041 * modifications to the underlying iterator will directly be visible in this
042 * wrapper.
043 */
044 public UnmodifiableListIterator(ListIterator<T> i) {
045 super(i);
046 this.i = i;
047 }
048
049 /** {@inheritDoc} */
050 public boolean hasPrevious() {
051 return i.hasPrevious();
052 }
053
054 /** {@inheritDoc} */
055 public int nextIndex() {
056 return i.nextIndex();
057 }
058
059 /** {@inheritDoc} */
060 public T previous() {
061 return i.previous();
062 }
063
064 /** {@inheritDoc} */
065 public int previousIndex() {
066 return i.previousIndex();
067 }
068
069 /**
070 * Operation is not supported.
071 *
072 * @throws UnsupportedOperationException
073 */
074 public void add(T o) {
075 throw new UnsupportedOperationException();
076 }
077
078 /**
079 * Operation is not supported.
080 *
081 * @throws UnsupportedOperationException
082 */
083 public void set(T o) {
084 throw new UnsupportedOperationException();
085 }
086
087 }