jdk/test/sun/management/HotspotClassLoadingMBean/GetClassLoadingTime.java
changeset 2 90ce3da70b43
child 403 dc6f4ca08b81
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/sun/management/HotspotClassLoadingMBean/GetClassLoadingTime.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,142 @@
+/*
+ * Copyright 2003 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug     4858522
+ * @summary Basic unit test of HotspotClassLoadingMBean.getClassLoadingTime()
+ * @author  Steve Bohne
+ * @build ClassToLoad0
+ */
+
+/*
+ * This test is just a sanity check and does not check for the correct value.
+ */
+
+import java.io.*;
+import sun.management.*;
+
+public class GetClassLoadingTime {
+
+    private static HotspotClassLoadingMBean mbean =
+        (HotspotClassLoadingMBean)ManagementFactory.getHotspotClassLoadingMBean();
+
+    // Careful with these values.
+    private static final long MIN_TIME_FOR_PASS = 1;
+    private static final long MAX_TIME_FOR_PASS = Long.MAX_VALUE;
+
+    private static boolean trace = false;
+
+    public static void main(String args[]) throws Exception {
+        if (args.length > 0 && args[0].equals("trace")) {
+            trace = true;
+        }
+
+        long time = mbean.getClassLoadingTime();
+
+        if (trace) {
+            System.out.println("Class loading time (ms): " + time);
+        }
+
+        if (time < MIN_TIME_FOR_PASS || time > MAX_TIME_FOR_PASS) {
+            throw new RuntimeException("Class loading time " +
+                                       "illegal value: " + time + " ms " +
+                                       "(MIN = " + MIN_TIME_FOR_PASS + "; " +
+                                       "MAX = " + MAX_TIME_FOR_PASS + ")");
+        }
+
+        // Load some classes to increase the time
+        for (int i = 0; i < 1000; i++) {
+            Class.forName("ClassToLoad0", true, new KlassLoader());
+        }
+
+        long time2 = mbean.getClassLoadingTime();
+        long count = mbean.getLoadedClassCount();
+
+        if (trace) {
+            System.out.println("(new count is " + count + ")");
+            System.out.println("Class loading time2 (ms): " + time2);
+        }
+
+        if (time2 <= time) {
+            throw new RuntimeException("Class loading time " +
+                                       "did not increase when class loaded" +
+                                       "(time = " + time + "; " +
+                                       "time2 = " + time2 + ")");
+        }
+
+        System.out.println("Test passed.");
+    }
+}
+
+// KlassLoader exists to load classes without a parent classloader,
+// so we can avoid delegation and spend lots of time loading the
+// same class over and over, to test the class loading timer.
+class KlassLoader extends ClassLoader {
+  static String klassDir="";
+  static int index=0;
+
+  public KlassLoader() {
+      super(null);
+  }
+
+  protected synchronized Class findClass(String name)
+                        throws ClassNotFoundException {
+        String cname = klassDir
+            + (klassDir == "" ? "" : "/")
+            +name.replace('.', '/')
+            +".class";
+
+        FileInputStream in;
+        try {
+                in=new FileInputStream(cname);
+                if (in == null) {
+                        throw new ClassNotFoundException("getResourceAsStream("
+                                +cname+")");
+                }
+        } catch(java.io.FileNotFoundException e ) {
+                throw new ClassNotFoundException("getResourceAsStream("
+                        +cname+") : "
+                        +e);
+        }
+
+        int len;
+        byte data[];
+        try {
+                len = in.available();
+                data = new byte[len];
+                for (int total = 0; total < data.length; ) {
+                        total += in.read(data, total, data.length - total);
+                }
+        } catch (IOException e) {
+                throw new ClassNotFoundException(cname, e);
+        } finally {
+                try {
+                        in.close();
+                } catch (IOException e) {
+                }
+        }
+
+        return defineClass(name, data, 0, data.length);
+  }
+}