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.util.Comparator;
020 import java.util.SortedMap;
021
022 import org.apache.commons.collections.Predicate;
023
024 /**
025 * Decorates another <code>SortedMap </code> to validate that additions
026 * match a specified predicate.
027 * <p>
028 * This map exists to provide validation for the decorated map.
029 * It is normally created to decorate an empty map.
030 * If an object cannot be added to the map, an IllegalArgumentException is thrown.
031 * <p>
032 * One usage would be to ensure that no null keys are added to the map.
033 * <pre>SortedMap map = PredicatedSortedSet.decorate(new TreeMap(), NotNullPredicate.INSTANCE, null);</pre>
034 * <p>
035 * <strong>Note that PredicatedSortedMap is not synchronized and is not thread-safe.</strong>
036 * If you wish to use this map from multiple threads concurrently, you must use
037 * appropriate synchronization. The simplest approach is to wrap this map
038 * using {@link java.util.Collections#synchronizedSortedMap}. This class may throw
039 * exceptions when accessed by concurrent threads without synchronization.
040 * <p>
041 * This class is Serializable from Commons Collections 3.1.
042 *
043 * @since Commons Collections 3.0
044 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
045 *
046 * @author Stephen Colebourne
047 * @author Paul Jack
048 */
049 public class PredicatedSortedMap
050 extends PredicatedMap
051 implements SortedMap {
052
053 /** Serialization version */
054 private static final long serialVersionUID = 3359846175935304332L;
055
056 /**
057 * Factory method to create a predicated (validating) sorted map.
058 * <p>
059 * If there are any elements already in the list being decorated, they
060 * are validated.
061 *
062 * @param map the map to decorate, must not be null
063 * @param keyPredicate the predicate to validate the keys, null means no check
064 * @param valuePredicate the predicate to validate to values, null means no check
065 * @throws IllegalArgumentException if the map is null
066 */
067 public static SortedMap decorate(SortedMap map, Predicate keyPredicate, Predicate valuePredicate) {
068 return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
069 }
070
071 //-----------------------------------------------------------------------
072 /**
073 * Constructor that wraps (not copies).
074 *
075 * @param map the map to decorate, must not be null
076 * @param keyPredicate the predicate to validate the keys, null means no check
077 * @param valuePredicate the predicate to validate to values, null means no check
078 * @throws IllegalArgumentException if the map is null
079 */
080 protected PredicatedSortedMap(SortedMap map, Predicate keyPredicate, Predicate valuePredicate) {
081 super(map, keyPredicate, valuePredicate);
082 }
083
084 //-----------------------------------------------------------------------
085 /**
086 * Gets the map being decorated.
087 *
088 * @return the decorated map
089 */
090 protected SortedMap getSortedMap() {
091 return (SortedMap) map;
092 }
093
094 //-----------------------------------------------------------------------
095 public Object firstKey() {
096 return getSortedMap().firstKey();
097 }
098
099 public Object lastKey() {
100 return getSortedMap().lastKey();
101 }
102
103 public Comparator comparator() {
104 return getSortedMap().comparator();
105 }
106
107 public SortedMap subMap(Object fromKey, Object toKey) {
108 SortedMap map = getSortedMap().subMap(fromKey, toKey);
109 return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
110 }
111
112 public SortedMap headMap(Object toKey) {
113 SortedMap map = getSortedMap().headMap(toKey);
114 return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
115 }
116
117 public SortedMap tailMap(Object fromKey) {
118 SortedMap map = getSortedMap().tailMap(fromKey);
119 return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
120 }
121
122 }