1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   5  * This code is free software; you can redistribute it and/or modify it
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   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
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  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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  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      */
  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      */
  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      */
  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      */
 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 }