src/share/classes/java/util/function/DoublePredicate.java

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rev 7675 : 8019840: Spec updates for java.util.function
Reviewed-by: mduigou
Contributed-by: brian.goetz@oracle.com


  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 {@code double} input value matches some criteria. This is
  31  * the {@code double}-consuming primitive type specialization of
  32  * {@link Predicate}.



  33  *
  34  * @see Predicate
  35  * @since 1.8
  36  */
  37 @FunctionalInterface
  38 public interface DoublePredicate {
  39 
  40     /**
  41      * Returns {@code true} if the input value matches some criteria.
  42      *
  43      * @param value the value to be tested
  44      * @return {@code true} if the input value matches some criteria, otherwise
  45      * {@code false}
  46      */
  47     boolean test(double value);
  48 
  49     /**
  50      * Returns a predicate which evaluates to {@code true} only if this
  51      * predicate and the provided predicate both evaluate to {@code true}. If
  52      * this predicate returns {@code false} then the remaining predicate is not
  53      * evaluated.
  54      *
  55      * <p>Any exceptions thrown by either {@code test} method are relayed
  56      * to the caller; if performing first operation throws an exception, the
  57      * second operation will not be performed.
  58      *
  59      * @param p a predicate which will be logically-ANDed with this predicate
  60      * @return a new predicate which returns {@code true} only if both
  61      * predicates return {@code true}
  62      * @throws NullPointerException if p is null

  63      */
  64     default DoublePredicate and(DoublePredicate p) {
  65         Objects.requireNonNull(p);
  66         return (value) -> test(value) && p.test(value);
  67     }
  68 
  69     /**
  70      * Returns a predicate which negates the result of this predicate.

  71      *
  72      * @return a new predicate who's result is always the opposite of this
  73      * predicate
  74      */
  75     default DoublePredicate negate() {
  76         return (value) -> !test(value);
  77     }
  78 
  79     /**
  80      * Returns a predicate which evaluates to {@code true} if either this
  81      * predicate or the provided predicate evaluates to {@code true}. If this
  82      * predicate returns {@code true} then the remaining predicate is not
  83      * evaluated.
  84      *
  85      * <p>Any exceptions thrown by either {@code test} method are relayed
  86      * to the caller; if performing first operation throws an exception, the
  87      * second operation will not be performed.
  88      *
  89      * @param p a predicate which will be logically-ANDed with this predicate
  90      * @return a new predicate which returns {@code true} if either predicate
  91      * returns {@code true}
  92      * @throws NullPointerException if p is null

  93      */
  94     default DoublePredicate or(DoublePredicate p) {
  95         Objects.requireNonNull(p);
  96         return (value) -> test(value) || p.test(value);
  97     }
  98 }


  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  * Represents a predicate (boolean-valued function) of one {@code double}-valued
  31  * argument. This is the {@code double}-consuming primitive type specialization
  32  * of {@link Predicate}.
  33  *
  34  * <p>This is a <a href="package-summary.html">functional interface</a>
  35  * whose functional method is {@link #test(double)}.
  36  *
  37  * @see Predicate
  38  * @since 1.8
  39  */
  40 @FunctionalInterface
  41 public interface DoublePredicate {
  42 
  43     /**
  44      * Evaluates this predicate on the given argument.
  45      *
  46      * @param value the input argument
  47      * @return {@code true} if the input argument matches the predicate,
  48      * otherwise {@code false}
  49      */
  50     boolean test(double value);
  51 
  52     /**
  53      * Returns a composed predicate that represents a short-circuiting logical
  54      * AND of this predicate and another.  When evaluating the composed
  55      * predicate, if this predicate is {@code false}, then the {@code other}
  56      * predicate is not evaluated.
  57      *
  58      * <p>Any exceptions thrown during evaluation of either predicate are relayed
  59      * to the caller; if evaluation of this predicate throws an exception, the
  60      * {@code other} predicate will not be evaluated.
  61      *
  62      * @param other a predicate that will be logically-ANDed with this
  63      *              predicate
  64      * @return a composed predicate that represents the short-circuiting logical
  65      * AND of this predicate and the {@code other} predicate
  66      * @throws NullPointerException if other is null
  67      */
  68     default DoublePredicate and(DoublePredicate other) {
  69         Objects.requireNonNull(other);
  70         return (value) -> test(value) && other.test(value);
  71     }
  72 
  73     /**
  74      * Returns a predicate that represents the logical negation of this
  75      * predicate.
  76      *
  77      * @return a predicate that represents the logical negation of this
  78      * predicate
  79      */
  80     default DoublePredicate negate() {
  81         return (value) -> !test(value);
  82     }
  83 
  84     /**
  85      * Returns a composed predicate that represents a short-circuiting logical
  86      * OR of this predicate and another.  When evaluating the composed
  87      * predicate, if this predicate is {@code true}, then the {@code other}
  88      * predicate is not evaluated.
  89      *
  90      * <p>Any exceptions thrown during evaluation of either predicate are relayed
  91      * to the caller; if evaluation of this predicate throws an exception, the
  92      * {@code other} predicate will not be evaluated.
  93      *
  94      * @param other a predicate that will be logically-ORed with this
  95      *              predicate
  96      * @return a composed predicate that represents the short-circuiting logical
  97      * OR of this predicate and the {@code other} predicate
  98      * @throws NullPointerException if other is null
  99      */
 100     default DoublePredicate or(DoublePredicate other) {
 101         Objects.requireNonNull(other);
 102         return (value) -> test(value) || other.test(value);
 103     }
 104 }