1 /*

     2  * Copyright (c) 2015, 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 org.openjdk.micro.jdk.java.util.stream;

    26 

    27 import java.util.ArrayList;

    28 import java.util.Arrays;

    29 import java.util.HashMap;

    30 import java.util.HashSet;

    31 import java.util.Random;

    32 import java.util.Set;

    33 import java.util.concurrent.ConcurrentHashMap;

    34 import java.util.function.BinaryOperator;

    35 import org.openjdk.jmh.annotations.Benchmark;

    36 import org.openjdk.jmh.annotations.Param;

    37 import org.openjdk.jmh.annotations.Scope;

    38 import org.openjdk.jmh.annotations.Setup;

    39 import org.openjdk.jmh.annotations.State;

    40 

    41 /**

    42  * JMH Benchmark created to mimic a JSR-166 benchmark

    43  */

    44 @State(Scope.Benchmark)

    45 public class IntegerSum {

    46 

    47     @Param({"1", "10", "100", "1000", "10000", "100000", "1000000"})

    48     private int size;

    49 

    50     private ArrayList<Integer> arrayList;

    51     private HashMap<Integer, Integer> hashMap;

    52     private ConcurrentHashMap<Integer, Integer> concurrentHashMap;

    53 

    54     private static final BinaryOperator<Integer> sum = (x, y) -> x + y;

    55 

    56     @Setup

    57     public final void setup() {

    58         Random srand = new Random(9820239874L);

    59         Set<Integer> set = new HashSet<>(size);

    60         while (set.size() < size) {

    61             set.add(srand.nextInt());

    62         }

    63         Integer[] values = set.toArray(new Integer[size]);

    64         Integer[] keys = Arrays.copyOf(values, size);

    65 

    66         for (int i = 0; i < size; i++) {

    67             swap(values, i, srand.nextInt(values.length));

    68             swap(keys, i, srand.nextInt(keys.length));

    69         }

    70 

    71         arrayList = new ArrayList<>(Arrays.asList(keys));

    72         hashMap = new HashMap<>(size);

    73         concurrentHashMap = new ConcurrentHashMap<>(size);

    74         for (int i = 0; i < size; i++) {

    75             hashMap.put(keys[i], values[i]);

    76             concurrentHashMap.put(keys[i], values[i]);

    77         }

    78 

    79         System.gc();

    80     }

    81 

    82     private void swap(Integer[] array, int first, int second) {

    83         Integer temp = array[first];

    84         array[first] = array[second];

    85         array[second] = temp;

    86     }

    87 

    88     @Benchmark

    89     public Integer ArrayListStream() {

    90         return arrayList.stream().reduce(0, sum);

    91     }

    92 

    93     @Benchmark

    94     public Integer HashMapStream() {

    95         return hashMap.keySet().stream().reduce(0, sum);

    96     }

    97 

    98     @Benchmark

    99     public Integer ConcurrentHashMapStream() {

   100         return concurrentHashMap.keySet().stream().reduce(0, sum);

   101     }

   102 

   103     @Benchmark

   104     public Integer ArrayListParallelStream() {

   105         return arrayList.parallelStream().reduce(0, sum);

   106     }

   107 

   108     @Benchmark

   109     public Integer HashMapParallelStream() {

   110         return hashMap.keySet().parallelStream().reduce(0, sum);

   111     }

   112 

   113     @Benchmark

   114     public Integer ConcurrentHashMapParallelStream() {

   115         return concurrentHashMap.keySet().parallelStream().reduce(0, sum);

   116     }

   117 }