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.map;
018    
019    import java.io.IOException;
020    import java.io.ObjectInputStream;
021    import java.io.ObjectOutputStream;
022    import java.io.Serializable;
023    import java.util.Collection;
024    import java.util.Comparator;
025    import java.util.Map;
026    import java.util.Set;
027    import java.util.SortedMap;
028    
029    import org.apache.commons.collections.Unmodifiable;
030    import org.apache.commons.collections.collection.UnmodifiableCollection;
031    import org.apache.commons.collections.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     *
038     * @since Commons Collections 3.0
039     * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
040     * 
041     * @author Stephen Colebourne
042     */
043    public final class UnmodifiableSortedMap
044            extends AbstractSortedMapDecorator
045            implements Unmodifiable, Serializable {
046    
047        /** Serialization version */
048        private static final long serialVersionUID = 5805344239827376360L;
049    
050        /**
051         * Factory method to create an unmodifiable sorted map.
052         * 
053         * @param map  the map to decorate, must not be null
054         * @throws IllegalArgumentException if map is null
055         */
056        public static SortedMap decorate(SortedMap map) {
057            if (map instanceof Unmodifiable) {
058                return map;
059            }
060            return new UnmodifiableSortedMap(map);
061        }
062    
063        //-----------------------------------------------------------------------
064        /**
065         * Constructor that wraps (not copies).
066         * 
067         * @param map  the map to decorate, must not be null
068         * @throws IllegalArgumentException if map is null
069         */
070        private UnmodifiableSortedMap(SortedMap map) {
071            super(map);
072        }
073    
074        //-----------------------------------------------------------------------
075        /**
076         * Write the map out using a custom routine.
077         * 
078         * @param out  the output stream
079         * @throws IOException
080         * @since Commons Collections 3.1
081         */
082        private void writeObject(ObjectOutputStream out) throws IOException {
083            out.defaultWriteObject();
084            out.writeObject(map);
085        }
086    
087        /**
088         * Read the map in using a custom routine.
089         * 
090         * @param in  the input stream
091         * @throws IOException
092         * @throws ClassNotFoundException
093         * @since Commons Collections 3.1
094         */
095        private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
096            in.defaultReadObject();
097            map = (Map) in.readObject();
098        }
099    
100        //-----------------------------------------------------------------------
101        public void clear() {
102            throw new UnsupportedOperationException();
103        }
104    
105        public Object put(Object key, Object value) {
106            throw new UnsupportedOperationException();
107        }
108    
109        public void putAll(Map mapToCopy) {
110            throw new UnsupportedOperationException();
111        }
112    
113        public Object remove(Object key) {
114            throw new UnsupportedOperationException();
115        }
116    
117        public Set entrySet() {
118            Set set = super.entrySet();
119            return UnmodifiableEntrySet.decorate(set);
120        }
121    
122        public Set keySet() {
123            Set set = super.keySet();
124            return UnmodifiableSet.decorate(set);
125        }
126    
127        public Collection values() {
128            Collection coll = super.values();
129            return UnmodifiableCollection.decorate(coll);
130        }
131    
132        //-----------------------------------------------------------------------
133        public Object firstKey() {
134            return getSortedMap().firstKey();
135        }
136    
137        public Object lastKey() {
138            return getSortedMap().lastKey();
139        }
140    
141        public Comparator comparator() {
142            return getSortedMap().comparator();
143        }
144    
145        public SortedMap subMap(Object fromKey, Object toKey) {
146            SortedMap map = getSortedMap().subMap(fromKey, toKey);
147            return new UnmodifiableSortedMap(map);
148        }
149    
150        public SortedMap headMap(Object toKey) {
151            SortedMap map = getSortedMap().headMap(toKey);
152            return new UnmodifiableSortedMap(map);
153        }
154    
155        public SortedMap tailMap(Object fromKey) {
156            SortedMap map = getSortedMap().tailMap(fromKey);
157            return new UnmodifiableSortedMap(map);
158        }
159    
160    }