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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    *      https://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  
18  package org.apache.commons.collections4;
19  
20  /**
21   * Defines a functor interface implemented by classes that perform a predicate test on an object.
22   * <p>
23   * A {@code Predicate} is the object equivalent of an {@code if} statement. It uses the input object to return a true or false value, and is often used in
24   * validation or filtering.
25   * </p>
26   * <p>
27   * Standard implementations of common predicates are provided by {@link PredicateUtils}. These include true, false, instanceof, equals, and, or, not, method
28   * invocation and null testing.
29   * </p>
30   *
31   * @param <T> The type of the input to the predicate.
32   * @since 1.0 This will be deprecated in 5.0 in favor of {@link Predicate}.
33   */
34  //@Deprecated
35  public interface Predicate<T> extends java.util.function.Predicate<T> {
36  
37      /**
38       * Use the specified parameter to perform a test that returns true or false.
39       *
40       * @param object The object to evaluate, should not be changed.
41       * @return true or false.
42       * @throws ClassCastException       (runtime) if the input is the wrong class.
43       * @throws IllegalArgumentException (runtime) if the input is invalid.
44       * @throws FunctorException         (runtime) if the predicate encounters a problem.
45       */
46      boolean evaluate(T object);
47  
48      @Override
49      default boolean test(final T t) {
50          return evaluate(t);
51      }
52  }