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.  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.bench.java.io;
  26 
  27 import java.io.File;
  28 import java.io.FileInputStream;
  29 import java.io.FileNotFoundException;
  30 import java.io.FileOutputStream;
  31 import java.io.IOException;
  32 import java.util.concurrent.TimeUnit;
  33 
  34 import org.openjdk.jmh.annotations.*;
  35 
  36 /**
  37  * Tests the overheads of I/O API.
  38  * This test is known to depend heavily on disk subsystem performance.
  39  */
  40 @BenchmarkMode(Mode.Throughput)
  41 @OutputTimeUnit(TimeUnit.MILLISECONDS)
  42 @State(Scope.Thread)
  43 public class FileRead {
  44 
  45     @Param("1000000")
  46     private int fileSize;
  47 
  48     private File f;
  49     private FileInputStream fis;
  50 
  51     @Setup(Level.Trial)
  52     public void beforeRun() throws IOException {
  53         f = File.createTempFile("FileReadBench", ".bin");
  54         try (FileOutputStream fos = new FileOutputStream(f)) {
  55             for (int i = 0; i < fileSize; i++) {
  56                 fos.write((byte) i);
  57             }
  58         }
  59     }
  60 
  61     @TearDown(Level.Trial)
  62     public void afterRun() throws IOException {
  63         f.delete();
  64     }
  65 
  66     @Setup(Level.Iteration)
  67     public void beforeIteration() throws FileNotFoundException {
  68         fis = new FileInputStream(f);
  69     }
  70 
  71     @TearDown(Level.Iteration)
  72     public void afterIteration() throws IOException {
  73         fis.close();
  74     }
  75 
  76     @Benchmark
  77     public void test() throws IOException {
  78         int ret = fis.read();
  79         if (ret == -1) {
  80             // start over
  81             fis.close();
  82             fis = new FileInputStream(f);
  83         }
  84     }
  85 
  86 }