1/*
2 * Copyright (c) 2004, 2009, 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
25package sun.jvm.hotspot.utilities.soql;
26
27import java.util.*;
28import sun.jvm.hotspot.debugger.*;
29import sun.jvm.hotspot.oops.*;
30import sun.jvm.hotspot.runtime.*;
31
32/**
33 * Wraps a JavaThread instance in the target VM.
34 */
35public class JSJavaThread extends JSJavaInstance {
36    public JSJavaThread(Instance threadOop, JSJavaFactory fac) {
37        super(threadOop, fac);
38        // JavaThread retrieved from java.lang.Thread instance may be null.
39        // This is the case for threads not-started and for zombies. Wherever
40        // appropriate, check for null instead of resulting in NullPointerException.
41        this.jthread = OopUtilities.threadOopGetJavaThread(threadOop);
42    }
43
44    public JSJavaThread(JavaThread jt, JSJavaFactory fac) {
45        super((Instance) jt.getThreadObj(), fac);
46        this.jthread = jt;
47    }
48
49    public String toString() {
50        String name = getName();
51        StringBuffer buf = new StringBuffer();
52        buf.append("Thread (address=");
53        buf.append(getOop().getHandle());
54        buf.append(", name=");
55        if (name != null) {
56            buf.append(name);
57        } else {
58            buf.append("<unnamed>");
59        }
60        buf.append(')');
61        return buf.toString();
62    }
63
64    protected Object getFieldValue(String name) {
65        if (name.equals("name")) {
66            return getName();
67        } else if (name.equals("frames")) {
68            return getFrames();
69        } else if (name.equals("monitors")) {
70            return getOwnedMonitors();
71        } else {
72            return super.getFieldValue(name);
73        }
74    }
75
76    protected String[] getFieldNames() {
77        String[] flds = super.getFieldNames();
78        String[] res = new String[flds.length + 2];
79        System.arraycopy(flds, 0, res, 0, flds.length);
80        res[flds.length] = "frames";
81        res[flds.length + 1] = "monitors";
82        return res;
83    }
84
85    protected boolean hasField(String name) {
86        if (name.equals("frames") || name.equals("monitors")) {
87            return true;
88        } else {
89            return super.hasField(name);
90        }
91    }
92
93    //-- Internals only below this point
94    private String getName() {
95        return OopUtilities.threadOopGetName(getOop());
96    }
97
98    private synchronized JSList getFrames() {
99        if (framesCache == null) {
100            final List list = new ArrayList(0);
101            if (jthread != null) {
102                JavaVFrame jvf = jthread.getLastJavaVFrameDbg();
103                while (jvf != null) {
104                    list.add(jvf);
105                    jvf = jvf.javaSender();
106                }
107            }
108            framesCache = factory.newJSList(list);
109        }
110        return framesCache;
111    }
112
113    private synchronized JSList getOwnedMonitors() {
114        if (monitorsCache == null) {
115            final List ownedMonitors = new ArrayList(0);
116            if (jthread != null) {
117                List lockedObjects = new ArrayList(); // List<OopHandle>
118
119                ObjectMonitor waitingMonitor = jthread.getCurrentWaitingMonitor();
120                OopHandle waitingObj = null;
121                if (waitingMonitor != null) {
122                   // save object of current wait() call (if any) for later comparison
123                   waitingObj = waitingMonitor.object();
124                }
125
126                ObjectMonitor pendingMonitor = jthread.getCurrentPendingMonitor();
127                OopHandle pendingObj = null;
128                if (pendingMonitor != null) {
129                    // save object of current enter() call (if any) for later comparison
130                    pendingObj = pendingMonitor.object();
131                }
132
133                JavaVFrame frame = jthread.getLastJavaVFrameDbg();
134                while (frame != null) {
135                    List frameMonitors = frame.getMonitors();  // List<MonitorInfo>
136                    for (Iterator miItr = frameMonitors.iterator(); miItr.hasNext(); ) {
137                        MonitorInfo mi = (MonitorInfo) miItr.next();
138
139                        if (mi.eliminated() && frame.isCompiledFrame()) {
140                          continue; // skip eliminated monitor
141                        }
142                        OopHandle obj = mi.owner();
143                        if (obj == null) {
144                            // this monitor doesn't have an owning object so skip it
145                            continue;
146                        }
147
148                        if (obj.equals(waitingObj)) {
149                           // the thread is waiting on this monitor so it isn't really owned
150                           continue;
151                        }
152
153                        if (obj.equals(pendingObj)) {
154                            // the thread is pending on this monitor so it isn't really owned
155                            continue;
156                        }
157
158                        boolean found = false;
159                        for (Iterator loItr = lockedObjects.iterator(); loItr.hasNext(); ) {
160                            // check for recursive locks
161                            if (obj.equals(loItr.next())) {
162                                found = true;
163                                break;
164                            }
165                        }
166                        if (found) {
167                            // already have this object so don't include it
168                            continue;
169                        }
170                        // add the owning object to our list
171                        lockedObjects.add(obj);
172                    }
173                    frame = (JavaVFrame) frame.javaSender();
174                }
175
176                // now convert List<OopHandle> to List<Oop>
177                ObjectHeap heap = VM.getVM().getObjectHeap();
178                for (Iterator loItr = lockedObjects.iterator(); loItr.hasNext(); ) {
179                    ownedMonitors.add(heap.newOop((OopHandle)loItr.next()));
180                }
181            }
182            monitorsCache = factory.newJSList(ownedMonitors);
183        }
184        return monitorsCache;
185    }
186
187    private JavaThread jthread;
188    private JSList framesCache;
189    private JSList monitorsCache;
190}
191