1 /*
   2  * Copyright (c) 2014 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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.openjdk.bench.java.util.stream.tasks.IntegerMax;
  24 
  25 import org.openjdk.jmh.annotations.Benchmark;
  26 import org.openjdk.jmh.annotations.BenchmarkMode;
  27 import org.openjdk.jmh.annotations.Level;
  28 import org.openjdk.jmh.annotations.Mode;
  29 import org.openjdk.jmh.annotations.OutputTimeUnit;
  30 import org.openjdk.jmh.annotations.Scope;
  31 import org.openjdk.jmh.annotations.Setup;
  32 import org.openjdk.jmh.annotations.State;
  33 
  34 import java.util.Arrays;
  35 import java.util.concurrent.TimeUnit;
  36 
  37 /**
  38  * Bulk scenario: search for max value in array.
  39  *
  40  * This test covers lambda-specific solutions for the problem.
  41  */
  42 @BenchmarkMode(Mode.Throughput)
  43 @OutputTimeUnit(TimeUnit.SECONDS)
  44 @State(Scope.Benchmark)
  45 public class Lambda {
  46 
  47     private IntegerMaxProblem problem;
  48 
  49     @Setup(Level.Trial)
  50     public void populateData(){
  51         problem = new IntegerMaxProblem();
  52     }
  53 
  54     public static Integer maxInt(Integer l, Integer r) {
  55         return l > r ? l : r;
  56     }
  57 
  58     @Benchmark
  59     public int bulk_seq_lambda() {
  60         return Arrays.stream(problem.get()).reduce(Integer.MIN_VALUE, (l, r) -> l > r ? l : r);
  61     }
  62 
  63     @Benchmark
  64     public int bulk_seq_methodRef() {
  65         return Arrays.stream(problem.get()).reduce(Integer.MIN_VALUE, Lambda::maxInt);
  66     }
  67 
  68     @Benchmark
  69     public int bulk_par_lambda() {
  70         return Arrays.stream(problem.get()).parallel().reduce(Integer.MIN_VALUE, (l, r) -> l > r ? l : r);
  71     }
  72 
  73     @Benchmark
  74     public int bulk_par_methodRef() {
  75         return Arrays.stream(problem.get()).parallel().reduce(Integer.MIN_VALUE, Lambda::maxInt);
  76     }
  77 
  78 }