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.util.Comparator; 020import java.util.SortedMap; 021 022import org.apache.commons.collections4.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 * <p> 033 * One usage would be to ensure that no null keys are added to the map. 034 * </p> 035 * <pre> 036 * SortedMap map = 037 * PredicatedSortedMap.predicatedSortedMap(new TreeMap(), 038 * NotNullPredicate.notNullPredicate(), 039 * null); 040 * </pre> 041 * <p> 042 * <strong>Note that PredicatedSortedMap is not synchronized and is not thread-safe.</strong> 043 * If you wish to use this map from multiple threads concurrently, you must use 044 * appropriate synchronization. The simplest approach is to wrap this map 045 * using {@link java.util.Collections#synchronizedSortedMap}. This class may throw 046 * exceptions when accessed by concurrent threads without synchronization. 047 * </p> 048 * <p> 049 * This class is Serializable from Commons Collections 3.1. 050 * </p> 051 * 052 * @param <K> the type of the keys in this map 053 * @param <V> the type of the values in this map 054 * @since 3.0 055 */ 056public class PredicatedSortedMap<K, V> extends PredicatedMap<K, V> implements SortedMap<K, V> { 057 058 /** Serialization version */ 059 private static final long serialVersionUID = 3359846175935304332L; 060 061 /** 062 * Factory method to create a predicated (validating) sorted map. 063 * <p> 064 * If there are any elements already in the list being decorated, they 065 * are validated. 066 * 067 * @param <K> the key type 068 * @param <V> the value type 069 * @param map the map to decorate, must not be null 070 * @param keyPredicate the predicate to validate the keys, null means no check 071 * @param valuePredicate the predicate to validate to values, null means no check 072 * @return a new predicated sorted map 073 * @throws NullPointerException if the map is null 074 * @since 4.0 075 */ 076 public static <K, V> PredicatedSortedMap<K, V> predicatedSortedMap(final SortedMap<K, V> map, 077 final Predicate<? super K> keyPredicate, final Predicate<? super V> valuePredicate) { 078 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 079 } 080 081 //----------------------------------------------------------------------- 082 /** 083 * Constructor that wraps (not copies). 084 * 085 * @param map the map to decorate, must not be null 086 * @param keyPredicate the predicate to validate the keys, null means no check 087 * @param valuePredicate the predicate to validate to values, null means no check 088 * @throws NullPointerException if the map is null 089 */ 090 protected PredicatedSortedMap(final SortedMap<K, V> map, final Predicate<? super K> keyPredicate, 091 final Predicate<? super V> valuePredicate) { 092 super(map, keyPredicate, valuePredicate); 093 } 094 095 //----------------------------------------------------------------------- 096 /** 097 * Gets the map being decorated. 098 * 099 * @return the decorated map 100 */ 101 protected SortedMap<K, V> getSortedMap() { 102 return (SortedMap<K, V>) map; 103 } 104 105 //----------------------------------------------------------------------- 106 @Override 107 public K firstKey() { 108 return getSortedMap().firstKey(); 109 } 110 111 @Override 112 public K lastKey() { 113 return getSortedMap().lastKey(); 114 } 115 116 @Override 117 public Comparator<? super K> comparator() { 118 return getSortedMap().comparator(); 119 } 120 121 @Override 122 public SortedMap<K, V> subMap(final K fromKey, final K toKey) { 123 final SortedMap<K, V> map = getSortedMap().subMap(fromKey, toKey); 124 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 125 } 126 127 @Override 128 public SortedMap<K, V> headMap(final K toKey) { 129 final SortedMap<K, V> map = getSortedMap().headMap(toKey); 130 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 131 } 132 133 @Override 134 public SortedMap<K, V> tailMap(final K fromKey) { 135 final SortedMap<K, V> map = getSortedMap().tailMap(fromKey); 136 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 137 } 138 139}