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  * Determines if the input objects match some criteria. This is the two-arity

    31  * specialization of {@link Predicate}.

    32  *

    33  * @param <T> the type of the first argument to {@code test}.

    34  * @param <U> the type of the second argument to {@code test}.

    35  *

    36  * @see Predicate

    37  * @since 1.8

    38  */

    39 @FunctionalInterface

    40 public interface BiPredicate<T, U> {

    41 

    42     /**

    43      * Return {@code true} if the inputs match some criteria.

    44      *

    45      * @param t an input object.

    46      * @param u an input object.

    47      * @return {@code true} if the inputs match some criteria.

    48      */

    49     boolean test(T t, U u);

    50 

    51     /**

    52      * Returns a predicate which evaluates to {@code true} only if this

    53      * predicate and the provided predicate both evaluate to {@code true}. If

    54      * this predicate returns {@code false} then the remaining predicate is not

    55      * evaluated.

    56      *

    57      * @param p a predicate which will be logically-ANDed with this predicate.

    58      * @return a new predicate which returns {@code true} only if both

    59      * predicates return {@code true}.

    60      */

    61     public default BiPredicate<T, U> and(BiPredicate<? super T, ? super U> p) {

    62         Objects.requireNonNull(p);

    63         return (T t, U u) -> test(t, u) && p.test(t, u);

    64     }

    65 

    66     /**

    67      * Returns a predicate which negates the result of this predicate.

    68      *

    69      * @return a new predicate who's result is always the opposite of this

    70      * predicate.

    71      */

    72     public default BiPredicate<T, U> negate() {

    73         return (T t, U u) -> !test(t, u);

    74     }

    75 

    76     /**

    77      * Returns a predicate which evaluates to {@code true} if either this

    78      * predicate or the provided predicate evaluates to {@code true}. If this

    79      * predicate returns {@code true} then the remaining predicate is not

    80      * evaluated.

    81      *

    82      * @param p a predicate which will be logically-ORed with this predicate.

    83      * @return a new predicate which returns {@code true} if either predicate

    84      * returns {@code true}.

    85      */

    86     public default BiPredicate<T, U> or(BiPredicate<? super T, ? super U> p) {

    87         Objects.requireNonNull(p);

    88         return (T t, U u) -> test(t, u) || p.test(t, u);

    89     }

    90 

    91     /**

    92      * Returns a predicate that evaluates to {@code true} if both or neither of

    93      * the component predicates evaluate to {@code true}.

    94      *

    95      * @param p a predicate which will be logically-XORed with this predicate.

    96      * @return a predicate that evaluates to {@code true} if both or neither of

    97      * the component predicates evaluate to {@code true}.

    98      */

    99     public default BiPredicate<T, U> xor(BiPredicate<? super T, ? super U> p) {

   100         Objects.requireNonNull(p);

   101         return (T t, U u) -> test(t, u) ^ p.test(t, u);

   102     }

   103 }