BiPredicate.java revision 607050af5a16c46ae53ff4d2c3f47b4ef694b559 
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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 * @hide 1.8
42 */
43@FunctionalInterface
44public interface BiPredicate<T, U> {
45
46    /**
47     * Evaluates this predicate on the given arguments.
48     *
49     * @param t the first input argument
50     * @param u the second input argument
51     * @return {@code true} if the input arguments match the predicate,
52     * otherwise {@code false}
53     */
54    boolean test(T t, U u);
55
56    /**
57     * Returns a composed predicate that represents a short-circuiting logical
58     * AND of this predicate and another.  When evaluating the composed
59     * predicate, if this predicate is {@code false}, then the {@code other}
60     * predicate is not evaluated.
61     *
62     * <p>Any exceptions thrown during evaluation of either predicate are relayed
63     * to the caller; if evaluation of this predicate throws an exception, the
64     * {@code other} predicate will not be evaluated.
65     *
66     * @param other a predicate that will be logically-ANDed with this
67     *              predicate
68     * @return a composed predicate that represents the short-circuiting logical
69     * AND of this predicate and the {@code other} predicate
70     * @throws NullPointerException if other is null
71     */
72    default BiPredicate<T, U> and(BiPredicate<? super T, ? super U> other) {
73        Objects.requireNonNull(other);
74        return (T t, U u) -> test(t, u) && other.test(t, u);
75    }
76
77    /**
78     * Returns a predicate that represents the logical negation of this
79     * predicate.
80     *
81     * @return a predicate that represents the logical negation of this
82     * predicate
83     */
84    default BiPredicate<T, U> negate() {
85        return (T t, U u) -> !test(t, u);
86    }
87
88    /**
89     * Returns a composed predicate that represents a short-circuiting logical
90     * OR of this predicate and another.  When evaluating the composed
91     * predicate, if this predicate is {@code true}, then the {@code other}
92     * predicate is not evaluated.
93     *
94     * <p>Any exceptions thrown during evaluation of either predicate are relayed
95     * to the caller; if evaluation of this predicate throws an exception, the
96     * {@code other} predicate will not be evaluated.
97     *
98     * @param other a predicate that will be logically-ORed with this
99     *              predicate
100     * @return a composed predicate that represents the short-circuiting logical
101     * OR of this predicate and the {@code other} predicate
102     * @throws NullPointerException if other is null
103     */
104    default BiPredicate<T, U> or(BiPredicate<? super T, ? super U> other) {
105        Objects.requireNonNull(other);
106        return (T t, U u) -> test(t, u) || other.test(t, u);
107    }
108}
109