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