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 }