1 /*
   2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  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      * @param p a predicate which will be logically-ANDed with this predicate
  56      * @return a new predicate which returns {@code true} only if both
  57      * predicates return {@code true}
  58      * @throws NullPointerException if p is null
  59      */
  60     default DoublePredicate and(DoublePredicate p) {
  61         Objects.requireNonNull(p);
  62         return (value) -> test(value) && p.test(value);
  63     }
  64 
  65     /**
  66      * Returns a predicate which negates the result of this predicate.
  67      *
  68      * @return a new predicate who's result is always the opposite of this
  69      * predicate
  70      */
  71     default DoublePredicate negate() {
  72         return (value) -> !test(value);
  73     }
  74 
  75     /**
  76      * Returns a predicate which evaluates to {@code true} if either this
  77      * predicate or the provided predicate evaluates to {@code true}. If this
  78      * predicate returns {@code true} then the remaining predicate is not
  79      * evaluated.
  80      *
  81      * @param p a predicate which will be logically-ANDed with this predicate
  82      * @return a new predicate which returns {@code true} if either predicate
  83      * returns {@code true}
  84      * @throws NullPointerException if p is null
  85      */
  86     default DoublePredicate or(DoublePredicate p) {
  87         Objects.requireNonNull(p);
  88         return (value) -> test(value) || p.test(value);
  89     }
  90 }