JavaObjectRef.java revision 2224:2a8815d86b93 
1/*
2 * Copyright (c) 1997, 2016, 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.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26
27/*
28 * The Original Code is HAT. The Initial Developer of the
29 * Original Code is Bill Foote, with contributions from others
30 * at JavaSoft/Sun.
31 */
32
33package jdk.test.lib.hprof.model;
34
35import jdk.test.lib.hprof.util.Misc;
36
37/**
38 * A forward reference to an object.  This is an intermediate representation
39 * for a JavaThing, when we have the thing's ID, but we might not have read
40 * the thing yet.
41 *
42 * @author      Bill Foote
43 */
44public class JavaObjectRef extends JavaThing {
45    private long id;
46
47    public JavaObjectRef(long id) {
48        this.id = id;
49    }
50
51    public long getId() {
52        return id;
53    }
54
55    public boolean isHeapAllocated() {
56        return true;
57    }
58
59    public JavaThing dereference(Snapshot snapshot, JavaField field) {
60        return dereference(snapshot, field, true);
61    }
62
63    public JavaThing dereference(Snapshot snapshot, JavaField field, boolean verbose) {
64        if (field != null && !field.hasId()) {
65            // If this happens, we must be a field that represents an int.
66            // (This only happens with .bod-style files)
67            return new JavaLong(id);
68        }
69        if (id == 0) {
70            return snapshot.getNullThing();
71        }
72        JavaThing result = snapshot.findThing(id);
73        if (result == null) {
74            if (!snapshot.getUnresolvedObjectsOK() && verbose) {
75                String msg = "WARNING:  Failed to resolve object id "
76                                + Misc.toHex(id);
77                if (field != null) {
78                    msg += " for field " + field.getName()
79                            + " (signature " + field.getSignature() + ")";
80                }
81                System.out.println(msg);
82                // Thread.dumpStack();
83            }
84            result = new HackJavaValue("Unresolved object "
85                                        + Misc.toHex(id), 0);
86        }
87        return result;
88    }
89
90    public int getSize() {
91        return 0;
92    }
93
94    public String toString() {
95        return "Unresolved object " + Misc.toHex(id);
96    }
97}
98