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1   /*
2    * Copyright (c) 2000, 2012, 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.oops;
26  
27  import java.io.*;
28  import java.util.*;
29  import sun.jvm.hotspot.debugger.*;
30  import sun.jvm.hotspot.runtime.*;
31  import sun.jvm.hotspot.types.*;
32  
33  // An Instance is an instance of a Java Class
34  
35  public class Instance extends Oop {
36    static {
37      VM.registerVMInitializedObserver(new Observer() {
38          public void update(Observable o, Object data) {
39            initialize(VM.getVM().getTypeDataBase());
40          }
41        });
42    }
43    private static long typeSize;
44  
45    private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
46      Type type = db.lookupType("instanceOopDesc");
47      typeSize = type.getSize();
48    }
49  
50    Instance(OopHandle handle, ObjectHeap heap) {
51      super(handle, heap);
52    }
53  
54    // Returns header size in bytes.
55    public static long getHeaderSize() {
56      if (VM.getVM().isCompressedKlassPointersEnabled()) {
57        return typeSize - VM.getVM().getIntSize();
58      } else {
59        return typeSize;
60      }
61    }
62  
63    public boolean isInstance()          { return true; }
64  
65    public void iterateFields(OopVisitor visitor, boolean doVMFields) {
66      super.iterateFields(visitor, doVMFields);
67      ((InstanceKlass) getKlass()).iterateNonStaticFields(visitor, this);
68    }
69  
70    public void printValueOn(PrintStream tty) {
71      // Special-case strings.
72      // FIXME: would like to do this in more type-safe fashion (need
73      // SystemDictionary analogue)
74      if (getKlass().getName().asString().equals("java/lang/String")) {
75        tty.print("\"" + OopUtilities.stringOopToString(this) + "\"");
76      } else {
77        super.printValueOn(tty);
78      }
79    }
80  }