jdk/src/share/classes/java/util/function/BiPredicate.java

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package java.util.function;

import java.util.Objects;

/**
 * Determines if the input objects match some criteria. This is the two-arity
 * specialization of {@link Predicate}.
 *
 * @param <T> the type of the first argument to {@code test}
 * @param <U> the type of the second argument to {@code test}
 *
 * @see Predicate
 * @since 1.8
 */
@FunctionalInterface
public interface BiPredicate<T, U> {

    /**
     * Return {@code true} if the inputs match some criteria.
     *
     * @param t an input object
     * @param u an input object
     * @return {@code true} if the inputs match some criteria
     */
    boolean test(T t, U u);

    /**
     * Returns a predicate which evaluates to {@code true} only if this
     * predicate and the provided predicate both evaluate to {@code true}. If
     * this predicate returns {@code false} then the remaining predicate is not
     * evaluated.
     *
     * @param p a predicate which will be logically-ANDed with this predicate
     * @return a new predicate which returns {@code true} only if both
     * predicates return {@code true}
     * @throws NullPointerException if p is null
     */
    default BiPredicate<T, U> and(BiPredicate<? super T, ? super U> p) {
        Objects.requireNonNull(p);
        return (T t, U u) -> test(t, u) && p.test(t, u);
    }

    /**
     * Returns a predicate which negates the result of this predicate.
     *
     * @return a new predicate who's result is always the opposite of this
     * predicate
     */
    default BiPredicate<T, U> negate() {
        return (T t, U u) -> !test(t, u);
    }

    /**
     * Returns a predicate which evaluates to {@code true} if either this
     * predicate or the provided predicate evaluates to {@code true}. If this
     * predicate returns {@code true} then the remaining predicate is not
     * evaluated.
     *
     * @param p a predicate which will be logically-ORed with this predicate
     * @return a new predicate which returns {@code true} if either predicate
     * returns {@code true}
     * @throws NullPointerException if p is null
     */
    default BiPredicate<T, U> or(BiPredicate<? super T, ? super U> p) {
        Objects.requireNonNull(p);
        return (T t, U u) -> test(t, u) || p.test(t, u);
    }
}