1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.collections4.map; 18 19 import java.util.Comparator; 20 import java.util.SortedMap; 21 22 import org.apache.commons.collections4.Predicate; 23 24 /** 25 * Decorates another {@code SortedMap} to validate that additions 26 * match a specified predicate. 27 * <p> 28 * This map exists to provide validation for the decorated map. 29 * It is normally created to decorate an empty map. 30 * If an object cannot be added to the map, an IllegalArgumentException is thrown. 31 * </p> 32 * <p> 33 * One usage would be to ensure that no null keys are added to the map. 34 * </p> 35 * <pre> 36 * SortedMap map = 37 * PredicatedSortedMap.predicatedSortedMap(new TreeMap(), 38 * NotNullPredicate.notNullPredicate(), 39 * null); 40 * </pre> 41 * <p> 42 * <strong>Note that PredicatedSortedMap is not synchronized and is not thread-safe.</strong> 43 * If you wish to use this map from multiple threads concurrently, you must use 44 * appropriate synchronization. The simplest approach is to wrap this map 45 * using {@link java.util.Collections#synchronizedSortedMap}. This class may throw 46 * exceptions when accessed by concurrent threads without synchronization. 47 * </p> 48 * <p> 49 * This class is Serializable from Commons Collections 3.1. 50 * </p> 51 * 52 * @param <K> the type of the keys in this map 53 * @param <V> the type of the values in this map 54 * @since 3.0 55 */ 56 public class PredicatedSortedMap<K, V> extends PredicatedMap<K, V> implements SortedMap<K, V> { 57 58 /** Serialization version */ 59 private static final long serialVersionUID = 3359846175935304332L; 60 61 /** 62 * Factory method to create a predicated (validating) sorted map. 63 * <p> 64 * If there are any elements already in the list being decorated, they 65 * are validated. 66 * 67 * @param <K> the key type 68 * @param <V> the value type 69 * @param map the map to decorate, must not be null 70 * @param keyPredicate the predicate to validate the keys, null means no check 71 * @param valuePredicate the predicate to validate to values, null means no check 72 * @return a new predicated sorted map 73 * @throws NullPointerException if the map is null 74 * @since 4.0 75 */ 76 public static <K, V> PredicatedSortedMap<K, V> predicatedSortedMap(final SortedMap<K, V> map, 77 final Predicate<? super K> keyPredicate, final Predicate<? super V> valuePredicate) { 78 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 79 } 80 81 /** 82 * Constructor that wraps (not copies). 83 * 84 * @param map the map to decorate, must not be null 85 * @param keyPredicate the predicate to validate the keys, null means no check 86 * @param valuePredicate the predicate to validate to values, null means no check 87 * @throws NullPointerException if the map is null 88 */ 89 protected PredicatedSortedMap(final SortedMap<K, V> map, final Predicate<? super K> keyPredicate, 90 final Predicate<? super V> valuePredicate) { 91 super(map, keyPredicate, valuePredicate); 92 } 93 94 @Override 95 public Comparator<? super K> comparator() { 96 return getSortedMap().comparator(); 97 } 98 99 @Override 100 public K firstKey() { 101 return getSortedMap().firstKey(); 102 } 103 104 /** 105 * Gets the map being decorated. 106 * 107 * @return the decorated map 108 */ 109 protected SortedMap<K, V> getSortedMap() { 110 return (SortedMap<K, V>) map; 111 } 112 113 @Override 114 public SortedMap<K, V> headMap(final K toKey) { 115 final SortedMap<K, V> map = getSortedMap().headMap(toKey); 116 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 117 } 118 119 @Override 120 public K lastKey() { 121 return getSortedMap().lastKey(); 122 } 123 124 @Override 125 public SortedMap<K, V> subMap(final K fromKey, final K toKey) { 126 final SortedMap<K, V> map = getSortedMap().subMap(fromKey, toKey); 127 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 128 } 129 130 @Override 131 public SortedMap<K, V> tailMap(final K fromKey) { 132 final SortedMap<K, V> map = getSortedMap().tailMap(fromKey); 133 return new PredicatedSortedMap<>(map, keyPredicate, valuePredicate); 134 } 135 136 }