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.set; 018 019import java.util.Comparator; 020import java.util.SortedSet; 021 022import org.apache.commons.collections4.Predicate; 023 024/** 025 * Decorates another <code>SortedSet</code> to validate that all additions 026 * match a specified predicate. 027 * <p> 028 * This set exists to provide validation for the decorated set. 029 * It is normally created to decorate an empty set. 030 * If an object cannot be added to the set, an IllegalArgumentException is thrown. 031 * <p> 032 * One usage would be to ensure that no null entries are added to the set. 033 * <pre> 034 * SortedSet set = 035 * PredicatedSortedSet.predicatedSortedSet(new TreeSet(), 036 * NotNullPredicate.notNullPredicate()); 037 * </pre> 038 * <p> 039 * This class is Serializable from Commons Collections 3.1. 040 * 041 * @param <E> the type of the elements in this set 042 * @since 3.0 043 */ 044public class PredicatedSortedSet<E> extends PredicatedSet<E> implements SortedSet<E> { 045 046 /** Serialization version */ 047 private static final long serialVersionUID = -9110948148132275052L; 048 049 /** 050 * Factory method to create a predicated (validating) sorted set. 051 * <p> 052 * If there are any elements already in the set being decorated, they 053 * are validated. 054 * 055 * @param <E> the element type 056 * @param set the set to decorate, must not be null 057 * @param predicate the predicate to use for validation, must not be null 058 * @return a new predicated sorted set. 059 * @throws NullPointerException if set or predicate is null 060 * @throws IllegalArgumentException if the set contains invalid elements 061 * @since 4.0 062 */ 063 public static <E> PredicatedSortedSet<E> predicatedSortedSet(final SortedSet<E> set, 064 final Predicate<? super E> predicate) { 065 return new PredicatedSortedSet<>(set, predicate); 066 } 067 068 //----------------------------------------------------------------------- 069 /** 070 * Constructor that wraps (not copies). 071 * <p> 072 * If there are any elements already in the set being decorated, they 073 * are validated. 074 * 075 * @param set the set to decorate, must not be null 076 * @param predicate the predicate to use for validation, must not be null 077 * @throws NullPointerException if set or predicate is null 078 * @throws IllegalArgumentException if the set contains invalid elements 079 */ 080 protected PredicatedSortedSet(final SortedSet<E> set, final Predicate<? super E> predicate) { 081 super(set, predicate); 082 } 083 084 /** 085 * Gets the sorted set being decorated. 086 * 087 * @return the decorated sorted set 088 */ 089 @Override 090 protected SortedSet<E> decorated() { 091 return (SortedSet<E>) super.decorated(); 092 } 093 094 //----------------------------------------------------------------------- 095 @Override 096 public Comparator<? super E> comparator() { 097 return decorated().comparator(); 098 } 099 100 @Override 101 public E first() { 102 return decorated().first(); 103 } 104 105 @Override 106 public E last() { 107 return decorated().last(); 108 } 109 110 @Override 111 public SortedSet<E> subSet(final E fromElement, final E toElement) { 112 final SortedSet<E> sub = decorated().subSet(fromElement, toElement); 113 return new PredicatedSortedSet<>(sub, predicate); 114 } 115 116 @Override 117 public SortedSet<E> headSet(final E toElement) { 118 final SortedSet<E> head = decorated().headSet(toElement); 119 return new PredicatedSortedSet<>(head, predicate); 120 } 121 122 @Override 123 public SortedSet<E> tailSet(final E fromElement) { 124 final SortedSet<E> tail = decorated().tailSet(fromElement); 125 return new PredicatedSortedSet<>(tail, predicate); 126 } 127 128}