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.map; 018 019import java.io.IOException; 020import java.io.ObjectInputStream; 021import java.io.ObjectOutputStream; 022import java.io.Serializable; 023import java.util.Collection; 024import java.util.Comparator; 025import java.util.Map; 026import java.util.Set; 027import java.util.SortedMap; 028 029import org.apache.commons.collections4.Unmodifiable; 030import org.apache.commons.collections4.collection.UnmodifiableCollection; 031import org.apache.commons.collections4.set.UnmodifiableSet; 032 033/** 034 * Decorates another <code>SortedMap</code> to ensure it can't be altered. 035 * <p> 036 * This class is Serializable from Commons Collections 3.1. 037 * <p> 038 * Attempts to modify it will result in an UnsupportedOperationException. 039 * 040 * @param <K> the type of the keys in this map 041 * @param <V> the type of the values in this map 042 * @since 3.0 043 */ 044public final class UnmodifiableSortedMap<K, V> 045 extends AbstractSortedMapDecorator<K, V> 046 implements Unmodifiable, Serializable { 047 048 /** Serialization version */ 049 private static final long serialVersionUID = 5805344239827376360L; 050 051 /** 052 * Factory method to create an unmodifiable sorted map. 053 * 054 * @param <K> the key type 055 * @param <V> the value type 056 * @param map the map to decorate, must not be null 057 * @return a new unmodifiable sorted map 058 * @throws NullPointerException if map is null 059 * @since 4.0 060 */ 061 public static <K, V> SortedMap<K, V> unmodifiableSortedMap(final SortedMap<K, ? extends V> map) { 062 if (map instanceof Unmodifiable) { 063 @SuppressWarnings("unchecked") // safe to upcast 064 final SortedMap<K, V> tmpMap = (SortedMap<K, V>) map; 065 return tmpMap; 066 } 067 return new UnmodifiableSortedMap<>(map); 068 } 069 070 //----------------------------------------------------------------------- 071 /** 072 * Constructor that wraps (not copies). 073 * 074 * @param map the map to decorate, must not be null 075 * @throws NullPointerException if map is null 076 */ 077 @SuppressWarnings("unchecked") // safe to upcast 078 private UnmodifiableSortedMap(final SortedMap<K, ? extends V> map) { 079 super((SortedMap<K, V>) map); 080 } 081 082 //----------------------------------------------------------------------- 083 /** 084 * Write the map out using a custom routine. 085 * 086 * @param out the output stream 087 * @throws IOException if an error occurs while writing to the stream 088 * @since 3.1 089 */ 090 private void writeObject(final ObjectOutputStream out) throws IOException { 091 out.defaultWriteObject(); 092 out.writeObject(map); 093 } 094 095 /** 096 * Read the map in using a custom routine. 097 * 098 * @param in the input stream 099 * @throws IOException if an error occurs while reading from the stream 100 * @throws ClassNotFoundException if an object read from the stream can not be loaded 101 * @since 3.1 102 */ 103 @SuppressWarnings("unchecked") 104 private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException { 105 in.defaultReadObject(); 106 map = (Map<K, V>) in.readObject(); 107 } 108 109 //----------------------------------------------------------------------- 110 @Override 111 public void clear() { 112 throw new UnsupportedOperationException(); 113 } 114 115 @Override 116 public V put(final K key, final V value) { 117 throw new UnsupportedOperationException(); 118 } 119 120 @Override 121 public void putAll(final Map<? extends K, ? extends V> mapToCopy) { 122 throw new UnsupportedOperationException(); 123 } 124 125 @Override 126 public V remove(final Object key) { 127 throw new UnsupportedOperationException(); 128 } 129 130 @Override 131 public Set<Map.Entry<K, V>> entrySet() { 132 return UnmodifiableEntrySet.unmodifiableEntrySet(super.entrySet()); 133 } 134 135 @Override 136 public Set<K> keySet() { 137 return UnmodifiableSet.unmodifiableSet(super.keySet()); 138 } 139 140 @Override 141 public Collection<V> values() { 142 return UnmodifiableCollection.unmodifiableCollection(super.values()); 143 } 144 145 //----------------------------------------------------------------------- 146 @Override 147 public K firstKey() { 148 return decorated().firstKey(); 149 } 150 151 @Override 152 public K lastKey() { 153 return decorated().lastKey(); 154 } 155 156 @Override 157 public Comparator<? super K> comparator() { 158 return decorated().comparator(); 159 } 160 161 @Override 162 public SortedMap<K, V> subMap(final K fromKey, final K toKey) { 163 return new UnmodifiableSortedMap<>(decorated().subMap(fromKey, toKey)); 164 } 165 166 @Override 167 public SortedMap<K, V> headMap(final K toKey) { 168 return new UnmodifiableSortedMap<>(decorated().headMap(toKey)); 169 } 170 171 @Override 172 public SortedMap<K, V> tailMap(final K fromKey) { 173 return new UnmodifiableSortedMap<>(decorated().tailMap(fromKey)); 174 } 175 176}