src/share/classes/java/util/function/Predicate.java
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rev 7675 : 8019840: Spec updates for java.util.function
Reviewed-by: mduigou
Contributed-by: brian.goetz@oracle.com
*** 25,112 ****
package java.util.function;
import java.util.Objects;
/**
! * Determines if the input object matches some criteria.
*
! * @param <T> the type of argument to {@code test}
*
* @since 1.8
*/
@FunctionalInterface
public interface Predicate<T> {
/**
! * Returns {@code true} if the input object matches some criteria.
*
! * @param t the input object
! * @return {@code true} if the input object matches some criteria, otherwise
! * {@code false}
*/
boolean test(T t);
/**
! * 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.
! *
! * <p>Any exceptions thrown by either {@code test} method are relayed
! * to the caller; if performing first operation throws an exception, the
! * second operation will not be performed.
! *
! * @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 Predicate<T> and(Predicate<? super T> p) {
! Objects.requireNonNull(p);
! return (t) -> test(t) && p.test(t);
}
/**
! * 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 Predicate<T> negate() {
return (t) -> !test(t);
}
/**
! * 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.
! *
! * <p>Any exceptions thrown by either {@code test} method are relayed
! * to the caller; if performing first operation throws an exception, the
! * second operation will not be performed.
! *
! * @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 Predicate<T> or(Predicate<? super T> p) {
! Objects.requireNonNull(p);
! return (t) -> test(t) || p.test(t);
}
/**
! * Returns a predicate who's result matches
! * {@code Objects.equals(target, t)}.
*
! * @param <T> the type of values evaluated by the predicate
! * @param target the target value to be compared for equality
! * @return a predicate who's result matches
! * {@code Objects.equals(target, t)}
*/
! static <T> Predicate<T> isEqual(Object target) {
! return (null == target)
? Objects::isNull
! : object -> target.equals(object);
}
}
--- 25,119 ----
package java.util.function;
import java.util.Objects;
/**
! * Represents a predicate (boolean-valued function) of one argument.
*
! * <p>This is a <a href="package-summary.html">functional interface</a>
! * whose functional method is {@link #test(Object)}.
! *
! * @param <T> the type of the input to the predicate
*
* @since 1.8
*/
@FunctionalInterface
public interface Predicate<T> {
/**
! * Evaluates this predicate on the given argument.
*
! * @param t the input argument
! * @return {@code true} if the input argument matches the predicate,
! * otherwise {@code false}
*/
boolean test(T t);
/**
! * Returns a composed predicate that represents a short-circuiting logical
! * AND of this predicate and another. When evaluating the composed
! * predicate, if this predicate is {@code false}, then the {@code other}
! * predicate is not evaluated.
! *
! * <p>Any exceptions thrown during evaluation of either predicate are relayed
! * to the caller; if evaluation of this predicate throws an exception, the
! * {@code other} predicate will not be evaluated.
! *
! * @param other a predicate that will be logically-ANDed with this
! * predicate
! * @return a composed predicate that represents the short-circuiting logical
! * AND of this predicate and the {@code other} predicate
! * @throws NullPointerException if other is null
! */
! default Predicate<T> and(Predicate<? super T> other) {
! Objects.requireNonNull(other);
! return (t) -> test(t) && other.test(t);
}
/**
! * Returns a predicate that represents the logical negation of this
* predicate.
+ *
+ * @return a predicate that represents the logical negation of this
+ * predicate
*/
default Predicate<T> negate() {
return (t) -> !test(t);
}
/**
! * Returns a composed predicate that represents a short-circuiting logical
! * OR of this predicate and another. When evaluating the composed
! * predicate, if this predicate is {@code true}, then the {@code other}
! * predicate is not evaluated.
! *
! * <p>Any exceptions thrown during evaluation of either predicate are relayed
! * to the caller; if evaluation of this predicate throws an exception, the
! * {@code other} predicate will not be evaluated.
! *
! * @param other a predicate that will be logically-ORed with this
! * predicate
! * @return a composed predicate that represents the short-circuiting logical
! * OR of this predicate and the {@code other} predicate
! * @throws NullPointerException if other is null
! */
! default Predicate<T> or(Predicate<? super T> other) {
! Objects.requireNonNull(other);
! return (t) -> test(t) || other.test(t);
}
/**
! * Returns a predicate that tests if two arguments are equal according
! * to {@link Objects#equals(Object, Object)}.
*
! * @param <T> the type of arguments to the predicate
! * @param targetRef the object reference with which to compare for equality,
! * which may be {@code null}
! * @return a predicate that tests if two arguments are equal according
! * to {@link Objects#equals(Object, Object)}
*/
! static <T> Predicate<T> isEqual(Object targetRef) {
! return (null == targetRef)
? Objects::isNull
! : object -> targetRef.equals(object);
}
}