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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 none of the
26   * predicates return true.
27   * If the array of predicates is empty, then this predicate returns true.
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: NonePredicate.java 1436241 2013-01-21 09:49:21Z tn $
34   */
35  public final class NonePredicate<T> extends AbstractQuantifierPredicate<T> implements Serializable {
36  
37      /** Serial version UID */
38      private static final long serialVersionUID = 2007613066565892961L;
39  
40      /**
41       * Factory to create the predicate.
42       * <p>
43       * If the array is size zero, the predicate always returns true.
44       *
45       * @param <T> the type that the predicate queries
46       * @param predicates  the predicates to check, cloned, not null
47       * @return the <code>any</code> predicate
48       * @throws IllegalArgumentException if the predicates array is null
49       * @throws IllegalArgumentException if any predicate in the array is null
50       */
51      public static <T> Predicate<T> nonePredicate(final Predicate<? super T>... predicates) {
52          FunctorUtils.validate(predicates);
53          if (predicates.length == 0) {
54              return TruePredicate.<T>truePredicate();
55          }
56          return new NonePredicate<T>(FunctorUtils.copy(predicates));
57      }
58  
59      /**
60       * Factory to create the predicate.
61       * <p>
62       * If the collection is size zero, the predicate always returns true.
63       *
64       * @param <T> the type that the predicate queries
65       * @param predicates  the predicates to check, cloned, not null
66       * @return the <code>one</code> predicate
67       * @throws IllegalArgumentException if the predicates array is null
68       * @throws IllegalArgumentException if any predicate in the array is null
69       */
70      public static <T> Predicate<T> nonePredicate(final Collection<? extends Predicate<T>> predicates) {
71          final Predicate<? super T>[] preds = FunctorUtils.validate(predicates);
72          if (preds.length == 0) {
73              return TruePredicate.<T>truePredicate();
74          }
75          return new NonePredicate<T>(preds);
76      }
77  
78      /**
79       * Constructor that performs no validation.
80       * Use <code>getInstance</code> if you want that.
81       *
82       * @param predicates  the predicates to check, not cloned, not null
83       */
84      public NonePredicate(final Predicate<? super T>[] predicates) {
85          super(predicates);
86      }
87  
88      /**
89       * Evaluates the predicate returning false if any stored predicate returns false.
90       *
91       * @param object  the input object
92       * @return true if none of decorated predicates return true
93       */
94      public boolean evaluate(final T object) {
95          for (final Predicate<? super T> iPredicate : iPredicates) {
96              if (iPredicate.evaluate(object)) {
97                  return false;
98              }
99          }
100         return true;
101     }
102 
103 }