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1   /*
2    * Copyright (c) 2001, 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.runtime;
26  
27  import java.util.*;
28  
29  import sun.jvm.hotspot.debugger.*;
30  import sun.jvm.hotspot.types.*;
31  
32  public class BasicObjectLock extends VMObject {
33    static {
34      VM.registerVMInitializedObserver(new Observer() {
35          public void update(Observable o, Object data) {
36            initialize(VM.getVM().getTypeDataBase());
37          }
38        });
39    }
40  
41    private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
42      Type type  = db.lookupType("BasicObjectLock");
43      lockField  = type.getField("_lock");
44      objField   = type.getOopField("_obj");
45      size       = (int) type.getSize();
46    }
47  
48    private static sun.jvm.hotspot.types.Field    lockField;
49    private static sun.jvm.hotspot.types.OopField objField;
50    private static int        size;
51  
52    public BasicObjectLock(Address addr) {
53      super(addr);
54    }
55  
56    public OopHandle obj()  { return objField.getValue(addr); }
57    public BasicLock lock() { return new BasicLock(addr.addOffsetTo(lockField.getOffset())); }
58  
59    /** Note: Use frame::interpreter_frame_monitor_size() for the size
60        of BasicObjectLocks in interpreter activation frames since it
61        includes machine-specific padding. This routine returns a size
62        in BYTES in this system! */
63    public static int size() { return size; }
64  
65    /** Helper routine for Frames (also probably needed for iteration) */
66    public Address address() { return addr; }
67  }