Predicate.java

  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;

  18. /**
  19.  * Defines a functor interface implemented by classes that perform a predicate
  20.  * test on an object.
  21.  * <p>
  22.  * A {@code Predicate} is the object equivalent of an {@code if} statement.
  23.  * 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
  28.  * {@link PredicateUtils}. These include true, false, instanceof, equals, and,
  29.  * or, not, method invocation and null testing.
  30.  * </p>
  31.  *
  32.  * @param <T> the type of the input to the predicate.
  33.  * @since 1.0
  34.  * @deprecated Use {@link java.util.function.Predicate}.
  35.  */
  36. @Deprecated
  37. public interface Predicate<T> extends java.util.function.Predicate<T> {

  38.     /**
  39.      * Use the specified parameter to perform a test that returns true or false.
  40.      *
  41.      * @param object  the object to evaluate, should not be changed
  42.      * @return true or false
  43.      * @throws ClassCastException (runtime) if the input is the wrong class
  44.      * @throws IllegalArgumentException (runtime) if the input is invalid
  45.      * @throws FunctorException (runtime) if the predicate encounters a problem
  46.      */
  47.     boolean evaluate(T object);

  48.     @Override
  49.     default boolean test(final T t) {
  50.         return evaluate(t);
  51.     }

  52. }