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.functors;
018
019 import java.io.Serializable;
020 import java.util.Collection;
021
022 import org.apache.commons.collections.Predicate;
023
024 /**
025 * Predicate implementation that returns true if all the
026 * predicates return true.
027 * If the array of predicates is empty, then this predicate returns true.
028 * <p>
029 * NOTE: In versions prior to 3.2 an array size of zero or one
030 * threw an exception.
031 *
032 * @since Commons Collections 3.0
033 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
034 *
035 * @author Stephen Colebourne
036 * @author Matt Benson
037 */
038 public final class AllPredicate implements Predicate, PredicateDecorator, Serializable {
039
040 /** Serial version UID */
041 private static final long serialVersionUID = -3094696765038308799L;
042
043 /** The array of predicates to call */
044 private final Predicate[] iPredicates;
045
046 /**
047 * Factory to create the predicate.
048 * <p>
049 * If the array is size zero, the predicate always returns true.
050 * If the array is size one, then that predicate is returned.
051 *
052 * @param predicates the predicates to check, cloned, not null
053 * @return the <code>all</code> predicate
054 * @throws IllegalArgumentException if the predicates array is null
055 * @throws IllegalArgumentException if any predicate in the array is null
056 */
057 public static Predicate getInstance(Predicate[] predicates) {
058 FunctorUtils.validate(predicates);
059 if (predicates.length == 0) {
060 return TruePredicate.INSTANCE;
061 }
062 if (predicates.length == 1) {
063 return predicates[0];
064 }
065 predicates = FunctorUtils.copy(predicates);
066 return new AllPredicate(predicates);
067 }
068
069 /**
070 * Factory to create the predicate.
071 * <p>
072 * If the collection is size zero, the predicate always returns true.
073 * If the collection is size one, then that predicate is returned.
074 *
075 * @param predicates the predicates to check, cloned, not null
076 * @return the <code>all</code> predicate
077 * @throws IllegalArgumentException if the predicates array is null
078 * @throws IllegalArgumentException if any predicate in the array is null
079 */
080 public static Predicate getInstance(Collection predicates) {
081 Predicate[] preds = FunctorUtils.validate(predicates);
082 if (preds.length == 0) {
083 return TruePredicate.INSTANCE;
084 }
085 if (preds.length == 1) {
086 return preds[0];
087 }
088 return new AllPredicate(preds);
089 }
090
091 /**
092 * Constructor that performs no validation.
093 * Use <code>getInstance</code> if you want that.
094 *
095 * @param predicates the predicates to check, not cloned, not null
096 */
097 public AllPredicate(Predicate[] predicates) {
098 super();
099 iPredicates = predicates;
100 }
101
102 /**
103 * Evaluates the predicate returning true if all predicates return true.
104 *
105 * @param object the input object
106 * @return true if all decorated predicates return true
107 */
108 public boolean evaluate(Object object) {
109 for (int i = 0; i < iPredicates.length; i++) {
110 if (iPredicates[i].evaluate(object) == false) {
111 return false;
112 }
113 }
114 return true;
115 }
116
117 /**
118 * Gets the predicates, do not modify the array.
119 *
120 * @return the predicates
121 * @since Commons Collections 3.1
122 */
123 public Predicate[] getPredicates() {
124 return iPredicates;
125 }
126
127 }