1 /*
   2  * Copyright (c) 2003, 2008, 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  */
  31 
  32 /*
  33  * This test is just a sanity check and does not check for the correct value.
  34  */
  35 
  36 import java.io.*;
  37 import sun.management.*;
  38 
  39 public class GetClassLoadingTime {
  40 
  41     private static HotspotClassLoadingMBean mbean =
  42         (HotspotClassLoadingMBean)ManagementFactoryHelper.getHotspotClassLoadingMBean();
  43 
  44     // Careful with these values.
  45     private static final long MIN_TIME_FOR_PASS = 1;
  46     private static final long MAX_TIME_FOR_PASS = Long.MAX_VALUE;
  47 
  48     private static boolean trace = false;
  49 
  50     public static void main(String args[]) throws Exception {
  51         if (args.length > 0 && args[0].equals("trace")) {
  52             trace = true;
  53         }
  54 
  55         long time = mbean.getClassLoadingTime();
  56 
  57         if (trace) {
  58             System.out.println("Class loading time (ms): " + time);
  59         }
  60 
  61         if (time < MIN_TIME_FOR_PASS || time > MAX_TIME_FOR_PASS) {
  62             throw new RuntimeException("Class loading time " +
  63                                        "illegal value: " + time + " ms " +
  64                                        "(MIN = " + MIN_TIME_FOR_PASS + "; " +
  65                                        "MAX = " + MAX_TIME_FOR_PASS + ")");
  66         }
  67 
  68         // Load some classes to increase the time
  69         for (int i = 0; i < 1000; i++) {
  70             Class.forName("ClassToLoad0", true, new KlassLoader());
  71         }
  72 
  73         long time2 = mbean.getClassLoadingTime();
  74         long count = mbean.getLoadedClassCount();
  75 
  76         if (trace) {
  77             System.out.println("(new count is " + count + ")");
  78             System.out.println("Class loading time2 (ms): " + time2);
  79         }
  80 
  81         if (time2 <= time) {
  82             throw new RuntimeException("Class loading time " +
  83                                        "did not increase when class loaded" +
  84                                        "(time = " + time + "; " +
  85                                        "time2 = " + time2 + ")");
  86         }
  87 
  88         System.out.println("Test passed.");
  89     }
  90 }
  91 
  92 // KlassLoader exists to load classes without a parent classloader,
  93 // so we can avoid delegation and spend lots of time loading the
  94 // same class over and over, to test the class loading timer.
  95 class KlassLoader extends ClassLoader {
  96   static String klassDir="";
  97   static int index=0;
  98 
  99   public KlassLoader() {
 100       super(null);
 101   }
 102 
 103   protected synchronized Class findClass(String name)
 104                         throws ClassNotFoundException {
 105         String cname = klassDir
 106             + (klassDir == "" ? "" : "/")
 107             +name.replace('.', '/')
 108             +".class";
 109 
 110         FileInputStream in;
 111         try {
 112                 in=new FileInputStream(cname);
 113                 if (in == null) {
 114                         throw new ClassNotFoundException("getResourceAsStream("
 115                                 +cname+")");
 116                 }
 117         } catch(java.io.FileNotFoundException e ) {
 118                 throw new ClassNotFoundException("getResourceAsStream("
 119                         +cname+") : "
 120                         +e);
 121         }
 122 
 123         int len;
 124         byte data[];
 125         try {
 126                 len = in.available();
 127                 data = new byte[len];
 128                 for (int total = 0; total < data.length; ) {
 129                         total += in.read(data, total, data.length - total);
 130                 }
 131         } catch (IOException e) {
 132                 throw new ClassNotFoundException(cname, e);
 133         } finally {
 134                 try {
 135                         in.close();
 136                 } catch (IOException e) {
 137                 }
 138         }
 139 
 140         return defineClass(name, data, 0, data.length);
 141   }
 142 }