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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  
21  import org.apache.commons.collections.Predicate;
22  
23  /**
24   * Predicate implementation that returns true if either of the predicates return true.
25   *
26   * @since 3.0
27   * @version $Id: OrPredicate.java 1435965 2013-01-20 21:13:18Z tn $
28   */
29  public final class OrPredicate<T> implements Predicate<T>, PredicateDecorator<T>, Serializable {
30  
31      /** Serial version UID */
32      private static final long serialVersionUID = -8791518325735182855L;
33  
34      /** The array of predicates to call */
35      private final Predicate<? super T> iPredicate1;
36      /** The array of predicates to call */
37      private final Predicate<? super T> iPredicate2;
38  
39      /**
40       * Factory to create the predicate.
41       *
42       * @param <T> the type that the predicate queries
43       * @param predicate1  the first predicate to check, not null
44       * @param predicate2  the second predicate to check, not null
45       * @return the <code>and</code> predicate
46       * @throws IllegalArgumentException if either predicate is null
47       */
48      public static <T> Predicate<T> orPredicate(final Predicate<? super T> predicate1,
49                                                 final Predicate<? super T> predicate2) {
50          if (predicate1 == null || predicate2 == null) {
51              throw new IllegalArgumentException("Predicate must not be null");
52          }
53          return new OrPredicate<T>(predicate1, predicate2);
54      }
55  
56      /**
57       * Constructor that performs no validation.
58       * Use <code>getInstance</code> if you want that.
59       *
60       * @param predicate1  the first predicate to check, not null
61       * @param predicate2  the second predicate to check, not null
62       */
63      public OrPredicate(final Predicate<? super T> predicate1, final Predicate<? super T> predicate2) {
64          super();
65          iPredicate1 = predicate1;
66          iPredicate2 = predicate2;
67      }
68  
69      /**
70       * Evaluates the predicate returning true if either predicate returns true.
71       *
72       * @param object  the input object
73       * @return true if either decorated predicate returns true
74       */
75      public boolean evaluate(final T object) {
76         return iPredicate1.evaluate(object) || iPredicate2.evaluate(object);
77      }
78  
79      /**
80       * Gets the two predicates being decorated as an array.
81       *
82       * @return the predicates
83       * @since 3.1
84       */
85      @SuppressWarnings("unchecked")
86      public Predicate<? super T>[] getPredicates() {
87          return new Predicate[] {iPredicate1, iPredicate2};
88      }
89  
90  }