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1   /*
2    * Copyright (c) 2002, 2007, 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  package sun.jvm.hotspot.ui;
26  
27  import java.awt.*;
28  import java.io.*;
29  import javax.swing.*;
30  import java.util.*;
31  
32  import sun.jvm.hotspot.memory.*;
33  import sun.jvm.hotspot.runtime.*;
34  import sun.jvm.hotspot.debugger.*;
35  import sun.jvm.hotspot.oops.*;
36  
37  /** Provides information about monitor cache. */
38  
39  public class MonitorCacheDumpPanel extends JPanel {
40    public MonitorCacheDumpPanel() {
41      super();
42  
43      setLayout(new BorderLayout());
44  
45      // Simple at first
46      JScrollPane scroller = new JScrollPane();
47      JTextArea textArea = new JTextArea();
48      textArea = new JTextArea();
49      textArea.setEditable(false);
50      textArea.setLineWrap(true);
51      textArea.setWrapStyleWord(true);
52      scroller.getViewport().add(textArea);
53      add(scroller, BorderLayout.CENTER);
54  
55      ByteArrayOutputStream bos = new ByteArrayOutputStream();
56      PrintStream tty = new PrintStream(bos);
57      tty.println("Monitor Cache Dump (not including JVMTI raw monitors):");
58      tty.println();
59      dumpOn(tty);
60  
61      textArea.setText(bos.toString());
62    }
63  
64    private static void dumpMonitor(PrintStream tty, ObjectMonitor mon, boolean raw) {
65      tty.print("ObjectMonitor@" + mon.getAddress());
66      if (raw) tty.print("(Raw Monitor)");
67      tty.println();
68      tty.println("  _header: 0x" + Long.toHexString(mon.header().value()));
69      OopHandle obj = mon.object();
70      Oop oop = heap.newOop(obj);
71      tty.println("  _object: " + obj + ", a " + oop.getKlass().getName().asString());
72      Address owner = mon.owner();
73      tty.println("  _owner: " + owner);
74      if (!raw && owner != null) {
75        JavaThread thread = threads.owningThreadFromMonitor(mon);
76        if (thread != null) {
77          tty.println("    owning thread: " + thread.getThreadName());
78          if (!thread.getAddress().equals(owner)) {
79            if (!thread.isLockOwned(owner)) {
80              tty.println("    WARNING! _owner doesn't fall in " + thread +
81                          "'s stack space");
82            }
83          }
84        }
85      }
86      tty.println("  _count: " + mon.count());
87      tty.println("  _waiters: " + mon.waiters());
88      tty.println("  _recursions: " + mon.recursions());
89    }
90  
91    private void dumpOn(PrintStream tty) {
92      Iterator i = ObjectSynchronizer.objectMonitorIterator();
93      if (i == null) {
94        tty.println("This version of HotSpot VM doesn't support monitor cache dump.");
95        tty.println("You need 1.4.0_04, 1.4.1_01 or later versions");
96        return;
97      }
98      ObjectMonitor mon;
99      while (i.hasNext()) {
100       mon = (ObjectMonitor)i.next();
101       if (mon.count() != 0 || mon.waiters() != 0 || mon.owner() != null) {
102         OopHandle object = mon.object();
103         if (object == null) {
104           dumpMonitor(tty, mon, true);
105         } else {
106           dumpMonitor(tty, mon, false);
107         }
108       }
109     }
110   }
111 
112   private static Threads threads = VM.getVM().getThreads();
113   private static ObjectHeap heap = VM.getVM().getObjectHeap();
114 }