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      * @throws NullPointerException if p is null
  61      */
  62     default BiPredicate<T, U> and(BiPredicate<? super T, ? super U> p) {
  63         Objects.requireNonNull(p);
  64         return (T t, U u) -> test(t, u) && p.test(t, u);
  65     }
  66 
  67     /**
  68      * Returns a predicate which negates the result of this predicate.
  69      *
  70      * @return a new predicate who's result is always the opposite of this
  71      * predicate
  72      */
  73     default BiPredicate<T, U> negate() {
  74         return (T t, U u) -> !test(t, u);
  75     }
  76 
  77     /**
  78      * Returns a predicate which evaluates to {@code true} if either this
  79      * predicate or the provided predicate evaluates to {@code true}. If this
  80      * predicate returns {@code true} then the remaining predicate is not
  81      * evaluated.
  82      *
  83      * @param p a predicate which will be logically-ORed with this predicate
  84      * @return a new predicate which returns {@code true} if either predicate
  85      * returns {@code true}
  86      * @throws NullPointerException if p is null
  87      */
  88     default BiPredicate<T, U> or(BiPredicate<? super T, ? super U> p) {
  89         Objects.requireNonNull(p);
  90         return (T t, U u) -> test(t, u) || p.test(t, u);
  91     }
  92 }