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15 * accompanied this code).
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24 */
25package java.util.function;
26
27import 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
43public 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}
108