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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.collections.functors;
18  
19  import java.io.Serializable;
20  import java.util.Collection;
21  
22  import org.apache.commons.collections.Predicate;
23  
24  /**
25   * Predicate implementation that returns true if any of the
26   * predicates return true.
27   * If the array of predicates is empty, then this predicate returns false.
28   * <p>
29   * NOTE: In versions prior to 3.2 an array size of zero or one
30   * threw an exception.
31   *
32   * @since 3.0
33   * @version $Id: AnyPredicate.java 1436241 2013-01-21 09:49:21Z tn $
34   */
35  public final class AnyPredicate<T> extends AbstractQuantifierPredicate<T> implements Serializable {
36  
37      /** Serial version UID */
38      private static final long serialVersionUID = 7429999530934647542L;
39  
40      /**
41       * Factory to create the predicate.
42       * <p>
43       * If the array is size zero, the predicate always returns false.
44       * If the array is size one, then that predicate is returned.
45       *
46       * @param <T> the type that the predicate queries
47       * @param predicates  the predicates to check, cloned, not null
48       * @return the <code>any</code> predicate
49       * @throws IllegalArgumentException if the predicates array is null
50       * @throws IllegalArgumentException if any predicate in the array is null
51       */
52      @SuppressWarnings("unchecked")
53      public static <T> Predicate<T> anyPredicate(final Predicate<? super T>... predicates) {
54          FunctorUtils.validate(predicates);
55          if (predicates.length == 0) {
56              return FalsePredicate.<T>falsePredicate();
57          }
58          if (predicates.length == 1) {
59              return (Predicate<T>) predicates[0];
60          }
61          return new AnyPredicate<T>(FunctorUtils.copy(predicates));
62      }
63  
64      /**
65       * Factory to create the predicate.
66       * <p>
67       * If the collection is size zero, the predicate always returns false.
68       * If the collection is size one, then that predicate is returned.
69       *
70       * @param <T> the type that the predicate queries
71       * @param predicates  the predicates to check, cloned, not null
72       * @return the <code>all</code> predicate
73       * @throws IllegalArgumentException if the predicates array is null
74       * @throws IllegalArgumentException if any predicate in the array is null
75       */
76      @SuppressWarnings("unchecked")
77      public static <T> Predicate<T> anyPredicate(final Collection<? extends Predicate<T>> predicates) {
78          final Predicate<? super T>[] preds = FunctorUtils.validate(predicates);
79          if (preds.length == 0) {
80              return FalsePredicate.<T>falsePredicate();
81          }
82          if (preds.length == 1) {
83              return (Predicate<T>) preds[0];
84          }
85          return new AnyPredicate<T>(preds);
86      }
87  
88      /**
89       * Constructor that performs no validation.
90       * Use <code>getInstance</code> if you want that.
91       *
92       * @param predicates  the predicates to check, not cloned, not null
93       */
94      public AnyPredicate(final Predicate<? super T>[] predicates) {
95          super(predicates);
96      }
97  
98      /**
99       * Evaluates the predicate returning true if any predicate returns true.
100      *
101      * @param object  the input object
102      * @return true if any decorated predicate return true
103      */
104     public boolean evaluate(final T object) {
105         for (final Predicate<? super T> iPredicate : iPredicates) {
106             if (iPredicate.evaluate(object)) {
107                 return true;
108             }
109         }
110         return false;
111     }
112 
113 }