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  * An operation which accepts a single double argument and returns no result.
  31  * This is the primitive type specialization of {@link Consumer} for
  32  * {@code double}. Unlike most other functional interfaces,
  33  * {@code DoubleConsumer} is expected to operate via side-effects.
  34  *
  35  * @see Consumer
  36  * @since 1.8
  37  */
  38 @FunctionalInterface
  39 public interface DoubleConsumer {
  40 
  41     /**
  42      * Accept an input value.
  43      *
  44      * @param value the input value
  45      */
  46     void accept(double value);
  47 
  48     /**
  49      * Returns a {@code DoubleConsumer} which performs, in sequence, the operation
  50      * represented by this object followed by the operation represented by
  51      * another {@code DoubleConsumer}.
  52      *
  53      * <p>Any exceptions thrown by either {@code accept} method are relayed
  54      * to the caller; if performing this operation throws an exception, the
  55      * other operation will not be performed.
  56      *
  57      * @param other a DoubleConsumer which will be chained after this
  58      * DoubleConsumer
  59      * @return an DoubleConsumer which performs in sequence the {@code accept} method
  60      * of this DoubleConsumer and the {@code accept} method of the specified IntConsumer
  61      * operation
  62      * @throws NullPointerException if other is null
  63      */
  64     default DoubleConsumer chain(DoubleConsumer other) {
  65         Objects.requireNonNull(other);
  66         return (double t) -> { accept(t); other.accept(t); };
  67     }
  68 }