1 /*
2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 package java.util.function;
26 
27 import java.util.Objects;
28 
29 /**
30  * Represents a predicate (boolean-valued function) of two arguments.  This is
31  * the two-arity specialization of {@link Predicate}.
32  *
33  * <p>This is a <a href="package-summary.html">functional interface</a>
34  * whose functional method is {@link #test(Object, Object)}.
35  *
36  * @param <T> the type of the first argument to the predicate
37  * @param <U> the type of the second argument the predicate
38  *
39  * @see Predicate
40  * @since 1.8
41  */
42 @FunctionalInterface
43 public interface BiPredicate<T, U> {
44 
45     /**
46      * Evaluates this predicate on the given arguments.
47      *
48      * @param t the first input argument
49      * @param u the second input argument
50      * @return {@code true} if the input arguments match the predicate,
51      * otherwise {@code false}
52      */
test(T t, U u)53     boolean test(T t, U u);
54 
55     /**
56      * Returns a composed predicate that represents a short-circuiting logical
57      * AND of this predicate and another.  When evaluating the composed
58      * predicate, if this predicate is {@code false}, then the {@code other}
59      * predicate is not evaluated.
60      *
61      * <p>Any exceptions thrown during evaluation of either predicate are relayed
62      * to the caller; if evaluation of this predicate throws an exception, the
63      * {@code other} predicate will not be evaluated.
64      *
65      * @param other a predicate that will be logically-ANDed with this
66      *              predicate
67      * @return a composed predicate that represents the short-circuiting logical
68      * AND of this predicate and the {@code other} predicate
69      * @throws NullPointerException if other is null
70      */
and(BiPredicate<? super T, ? super U> other)71     default BiPredicate<T, U> and(BiPredicate<? super T, ? super U> other) {
72         Objects.requireNonNull(other);
73         return (T t, U u) -> test(t, u) && other.test(t, u);
74     }
75 
76     /**
77      * Returns a predicate that represents the logical negation of this
78      * predicate.
79      *
80      * @return a predicate that represents the logical negation of this
81      * predicate
82      */
negate()83     default BiPredicate<T, U> negate() {
84         return (T t, U u) -> !test(t, u);
85     }
86 
87     /**
88      * Returns a composed predicate that represents a short-circuiting logical
89      * OR of this predicate and another.  When evaluating the composed
90      * predicate, if this predicate is {@code true}, then the {@code other}
91      * predicate is not evaluated.
92      *
93      * <p>Any exceptions thrown during evaluation of either predicate are relayed
94      * to the caller; if evaluation of this predicate throws an exception, the
95      * {@code other} predicate will not be evaluated.
96      *
97      * @param other a predicate that will be logically-ORed with this
98      *              predicate
99      * @return a composed predicate that represents the short-circuiting logical
100      * OR of this predicate and the {@code other} predicate
101      * @throws NullPointerException if other is null
102      */
or(BiPredicate<? super T, ? super U> other)103     default BiPredicate<T, U> or(BiPredicate<? super T, ? super U> other) {
104         Objects.requireNonNull(other);
105         return (T t, U u) -> test(t, u) || other.test(t, u);
106     }
107 }
108