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 */ 017package org.apache.commons.collections4.list; 018 019import java.util.Collection; 020import java.util.List; 021import java.util.ListIterator; 022 023import org.apache.commons.collections4.collection.AbstractCollectionDecorator; 024 025/** 026 * Decorates another {@link List} to provide additional behavior. 027 * <p> 028 * Methods are forwarded directly to the decorated list. 029 * </p> 030 * 031 * @param <E> the type of the elements in the list 032 * @since 3.0 033 */ 034public abstract class AbstractListDecorator<E> extends AbstractCollectionDecorator<E> 035 implements List<E> { 036 037 /** Serialization version--necessary in an abstract class? */ 038 private static final long serialVersionUID = 4500739654952315623L; 039 040 /** 041 * Constructor only used in deserialization, do not use otherwise. 042 * @since 3.1 043 */ 044 protected AbstractListDecorator() { 045 } 046 047 /** 048 * Constructor that wraps (not copies). 049 * 050 * @param list the list to decorate, must not be null 051 * @throws NullPointerException if list is null 052 */ 053 protected AbstractListDecorator(final List<E> list) { 054 super(list); 055 } 056 057 @Override 058 public void add(final int index, final E object) { 059 decorated().add(index, object); 060 } 061 062 @Override 063 public boolean addAll(final int index, final Collection<? extends E> coll) { 064 return decorated().addAll(index, coll); 065 } 066 067 /** 068 * Gets the list being decorated. 069 * 070 * @return the decorated list 071 */ 072 @Override 073 protected List<E> decorated() { 074 return (List<E>) super.decorated(); 075 } 076 077 @Override 078 public boolean equals(final Object object) { 079 return object == this || decorated().equals(object); 080 } 081 082 @Override 083 public E get(final int index) { 084 return decorated().get(index); 085 } 086 087 @Override 088 public int hashCode() { 089 return decorated().hashCode(); 090 } 091 092 @Override 093 public int indexOf(final Object object) { 094 return decorated().indexOf(object); 095 } 096 097 @Override 098 public int lastIndexOf(final Object object) { 099 return decorated().lastIndexOf(object); 100 } 101 102 @Override 103 public ListIterator<E> listIterator() { 104 return decorated().listIterator(); 105 } 106 107 @Override 108 public ListIterator<E> listIterator(final int index) { 109 return decorated().listIterator(index); 110 } 111 112 @Override 113 public E remove(final int index) { 114 return decorated().remove(index); 115 } 116 117 @Override 118 public E set(final int index, final E object) { 119 return decorated().set(index, object); 120 } 121 122 @Override 123 public List<E> subList(final int fromIndex, final int toIndex) { 124 return decorated().subList(fromIndex, toIndex); 125 } 126 127}