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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.collections4.functors;
18  
19  import java.util.Collection;
20  
21  import org.apache.commons.collections4.Predicate;
22  
23  /**
24   * Predicate implementation that returns true if none of the
25   * predicates return true.
26   * If the array of predicates is empty, then this predicate returns true.
27   * <p>
28   * NOTE: In versions prior to 3.2 an array size of zero or one
29   * threw an exception.
30   * </p>
31   *
32   * @param <T> the type of the input to the predicate.
33   * @since 3.0
34   */
35  public final class NonePredicate<T> extends AbstractQuantifierPredicate<T> {
36  
37      /** Serial version UID */
38      private static final long serialVersionUID = 2007613066565892961L;
39  
40      /**
41       * Creates the predicate.
42       * <p>
43       * If the collection is size zero, the predicate always returns true.
44       * </p>
45       *
46       * @param <T> the type that the predicate queries
47       * @param predicates  the predicates to check, cloned, not null
48       * @return the {@code one} predicate
49       * @throws NullPointerException if the predicates array is null
50       * @throws NullPointerException if any predicate in the array is null
51       */
52      public static <T> Predicate<T> nonePredicate(final Collection<? extends Predicate<? super T>> predicates) {
53          final Predicate<? super T>[] preds = FunctorUtils.validate(predicates);
54          if (preds.length == 0) {
55              return TruePredicate.<T>truePredicate();
56          }
57          return new NonePredicate<>(preds);
58      }
59  
60      /**
61       * Creates the predicate.
62       * <p>
63       * If the array is size zero, the predicate always returns true.
64       * </p>
65       *
66       * @param <T> the type that the predicate queries
67       * @param predicates  the predicates to check, cloned, not null
68       * @return the {@code any} predicate
69       * @throws NullPointerException if the predicates array is null
70       * @throws NullPointerException if any predicate in the array is null
71       */
72      public static <T> Predicate<T> nonePredicate(final Predicate<? super T>... predicates) {
73          FunctorUtils.validate(predicates);
74          if (predicates.length == 0) {
75              return TruePredicate.<T>truePredicate();
76          }
77          // <T> not needed in Eclipse but needed by the command line compiler
78          return new NonePredicate<T>(FunctorUtils.copy(predicates));
79      }
80  
81      /**
82       * Constructor that performs no validation.
83       * Use {@code nonePredicate} if you want that.
84       *
85       * @param predicates  the predicates to check, not cloned, not null
86       */
87      public NonePredicate(final Predicate<? super T>... predicates) {
88          super(predicates);
89      }
90  
91      /**
92       * Evaluates the predicate returning false if any stored predicate returns false.
93       *
94       * @param object  the input object
95       * @return true if none of decorated predicates return true
96       */
97      @Override
98      public boolean test(final T object) {
99          for (final Predicate<? super T> iPredicate : iPredicates) {
100             if (iPredicate.test(object)) {
101                 return false;
102             }
103         }
104         return true;
105     }
106 
107 }