1 /*
   2  * Copyright (c) 2003, 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.
   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 
  24 /*
  25  * @test
  26  * @bug     4858522
  27  * @summary Basic unit test of HotspotClassLoadingMBean.getClassLoadingTime()
  28  * @author  Steve Bohne
  29  * @build ClassToLoad0
  30  * @run main/othervm -XX:+UsePerfData GetClassLoadingTime
  31  */
  32 
  33 /*
  34  * This test is just a sanity check and does not check for the correct value.
  35  */
  36 
  37 import java.io.*;
  38 import sun.management.*;
  39 
  40 public class GetClassLoadingTime {
  41 
  42     private static HotspotClassLoadingMBean mbean =
  43         (HotspotClassLoadingMBean)ManagementFactoryHelper.getHotspotClassLoadingMBean();
  44 
  45     // Careful with these values.
  46     private static final long MIN_TIME_FOR_PASS = 1;
  47     private static final long MAX_TIME_FOR_PASS = Long.MAX_VALUE;
  48 
  49     private static boolean trace = false;
  50 
  51     public static void main(String args[]) throws Exception {
  52         if (args.length > 0 && args[0].equals("trace")) {
  53             trace = true;
  54         }
  55 
  56         long time = mbean.getClassLoadingTime();
  57 
  58         if (trace) {
  59             System.out.println("Class loading time (ms): " + time);
  60         }
  61 
  62         if (time < MIN_TIME_FOR_PASS || time > MAX_TIME_FOR_PASS) {
  63             throw new RuntimeException("Class loading time " +
  64                                        "illegal value: " + time + " ms " +
  65                                        "(MIN = " + MIN_TIME_FOR_PASS + "; " +
  66                                        "MAX = " + MAX_TIME_FOR_PASS + ")");
  67         }
  68 
  69         // Load some classes to increase the time
  70         for (int i = 0; i < 1000; i++) {
  71             Class.forName("ClassToLoad0", true, new KlassLoader());
  72         }
  73 
  74         long time2 = mbean.getClassLoadingTime();
  75 
  76         if (trace) {
  77             System.out.println("Class loading time2 (ms): " + time2);
  78         }
  79 
  80         if (time2 <= time) {
  81             throw new RuntimeException("Class loading time " +
  82                                        "did not increase when class loaded" +
  83                                        "(time = " + time + "; " +
  84                                        "time2 = " + time2 + ")");
  85         }
  86 
  87         System.out.println("Test passed.");
  88     }
  89 }
  90 
  91 // KlassLoader exists to load classes without a parent classloader,
  92 // so we can avoid delegation and spend lots of time loading the
  93 // same class over and over, to test the class loading timer.
  94 class KlassLoader extends ClassLoader {
  95 
  96   public KlassLoader() {
  97       super(null);
  98   }
  99 
 100   protected synchronized Class findClass(String name)
 101                         throws ClassNotFoundException {
 102         String cname =
 103             name.replace('.', '/')
 104             +".class";
 105 
 106         FileInputStream in;
 107         try {
 108                 in = new FileInputStream(new File(System.getProperty("test.classes", "."), cname));
 109                 if (in == null) {
 110                         throw new ClassNotFoundException("getResourceAsStream("
 111                                 +cname+")");
 112                 }
 113         } catch(java.io.FileNotFoundException e ) {
 114                 throw new ClassNotFoundException("getResourceAsStream("
 115                         +cname+") : "
 116                         +e);
 117         }
 118 
 119         int len;
 120         byte data[];
 121         try {
 122                 len = in.available();
 123                 data = new byte[len];
 124                 for (int total = 0; total < data.length; ) {
 125                         total += in.read(data, total, data.length - total);
 126                 }
 127         } catch (IOException e) {
 128                 throw new ClassNotFoundException(cname, e);
 129         } finally {
 130                 try {
 131                         in.close();
 132                 } catch (IOException e) {
 133                 }
 134         }
 135 
 136         return defineClass(name, data, 0, data.length);
 137   }
 138 }