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.util.*;
28
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.memory.*;
31 import sun.jvm.hotspot.runtime.*;
32 import sun.jvm.hotspot.types.TypeDataBase;
33 import sun.jvm.hotspot.utilities.*;
34 import sun.jvm.hotspot.jdi.JVMTIThreadState;
35
36 /** A utility class encapsulating useful oop operations */
37
38 public class OopUtilities implements /* imports */ JVMTIThreadState {
39
40 // FIXME: access should be synchronized and cleared when VM is
41 // resumed
42 // String fields
43 private static ByteField coderField;
44 private static OopField valueField;
45 // ThreadGroup fields
46 private static OopField threadGroupParentField;
47 private static OopField threadGroupNameField;
48 private static IntField threadGroupNThreadsField;
49 private static OopField threadGroupThreadsField;
50 private static IntField threadGroupNGroupsField;
51 private static OopField threadGroupGroupsField;
52 // Thread fields
53 private static OopField threadNameField;
54 private static OopField threadGroupField;
55 private static LongField threadEETopField;
56 //tid field is new since 1.5
57 private static LongField threadTIDField;
58 // threadStatus field is new since 1.5
59 private static IntField threadStatusField;
60 // parkBlocker field is new since 1.6
61 private static OopField threadParkBlockerField;
62
63 // possible values of java_lang_Thread::ThreadStatus
64 private static int THREAD_STATUS_NEW;
65 /*
66 Other enum constants are not needed as of now. Uncomment these as and when needed.
67
68 private static int THREAD_STATUS_RUNNABLE;
69 private static int THREAD_STATUS_SLEEPING;
70 private static int THREAD_STATUS_IN_OBJECT_WAIT;
71 private static int THREAD_STATUS_IN_OBJECT_WAIT_TIMED;
72 private static int THREAD_STATUS_PARKED;
73 private static int THREAD_STATUS_PARKED_TIMED;
74 private static int THREAD_STATUS_BLOCKED_ON_MONITOR_ENTER;
75 private static int THREAD_STATUS_TERMINATED;
76 */
77
78 // java.util.concurrent.locks.AbstractOwnableSynchronizer fields
79 private static OopField absOwnSyncOwnerThreadField;
80
81 static {
82 VM.registerVMInitializedObserver(new Observer() {
83 public void update(Observable o, Object data) {
84 initialize(VM.getVM().getTypeDataBase());
85 }
86 });
87 }
88
89 private static synchronized void initialize(TypeDataBase db) {
90 // FIXME: don't need this observer; however, do need a VM resumed
91 // and suspended observer to refetch fields
92 }
93
94 public static String charArrayToString(TypeArray charArray) {
95 if (charArray == null) {
96 return null;
97 }
98 int length = (int)charArray.getLength();
99 StringBuffer buf = new StringBuffer(length);
100 for (int i = 0; i < length; i++) {
101 buf.append(charArray.getCharAt(i));
102 }
103 return buf.toString();
104 }
105
106 public static String byteArrayToString(TypeArray byteArray, byte coder) {
107 if (byteArray == null) {
108 return null;
109 }
110 int length = (int)byteArray.getLength() >> coder;
111 StringBuffer buf = new StringBuffer(length);
112 if (coder == 0) {
113 // Latin1 encoded
114 for (int i = 0; i < length; i++) {
115 buf.append((char)(byteArray.getByteAt(i) & 0xff));
116 }
117 } else {
118 // UTF16 encoded
119 for (int i = 0; i < length; i++) {
120 buf.append(byteArray.getCharAt(i));
121 }
122 }
123 return buf.toString();
124 }
125
126 public static String escapeString(String s) {
127 StringBuilder sb = null;
128 for (int index = 0; index < s.length(); index++) {
129 char value = s.charAt(index);
130 if (value >= 32 && value < 127 || value == '\'' || value == '\\') {
131 if (sb != null) {
132 sb.append(value);
133 }
134 } else {
135 if (sb == null) {
136 sb = new StringBuilder(s.length() * 2);
137 sb.append(s, 0, index);
138 }
139 sb.append("\\u");
140 if (value < 0x10) sb.append("000");
141 else if (value < 0x100) sb.append("00");
142 else if (value < 0x1000) sb.append("0");
143 sb.append(Integer.toHexString(value));
144 }
145 }
146 if (sb != null) {
147 return sb.toString();
148 }
149 return s;
150 }
151
152 public static String stringOopToString(Oop stringOop) {
153 InstanceKlass k = (InstanceKlass) stringOop.getKlass();
154 coderField = (ByteField) k.findField("coder", "B");
155 valueField = (OopField) k.findField("value", "[B");
156 if (Assert.ASSERTS_ENABLED) {
157 Assert.that(coderField != null, "Field \'coder\' of java.lang.String not found");
158 Assert.that(valueField != null, "Field \'value\' of java.lang.String not found");
159 }
160 return byteArrayToString((TypeArray) valueField.getValue(stringOop), coderField.getValue(stringOop));
161 }
162
163 public static String stringOopToEscapedString(Oop stringOop) {
164 return escapeString(stringOopToString(stringOop));
165 }
166
167 private static void initThreadGroupFields() {
168 if (threadGroupParentField == null) {
169 SystemDictionary sysDict = VM.getVM().getSystemDictionary();
170 InstanceKlass k = sysDict.getThreadGroupKlass();
171 threadGroupParentField = (OopField) k.findField("parent", "Ljava/lang/ThreadGroup;");
172 threadGroupNameField = (OopField) k.findField("name", "Ljava/lang/String;");
173 threadGroupNThreadsField = (IntField) k.findField("nthreads", "I");
174 threadGroupThreadsField = (OopField) k.findField("threads", "[Ljava/lang/Thread;");
175 threadGroupNGroupsField = (IntField) k.findField("ngroups", "I");
176 threadGroupGroupsField = (OopField) k.findField("groups", "[Ljava/lang/ThreadGroup;");
177 if (Assert.ASSERTS_ENABLED) {
178 Assert.that(threadGroupParentField != null &&
179 threadGroupNameField != null &&
180 threadGroupNThreadsField != null &&
181 threadGroupThreadsField != null &&
182 threadGroupNGroupsField != null &&
183 threadGroupGroupsField != null, "must find all java.lang.ThreadGroup fields");
184 }
185 }
186 }
187
188 public static Oop threadGroupOopGetParent(Oop threadGroupOop) {
189 initThreadGroupFields();
190 return threadGroupParentField.getValue(threadGroupOop);
191 }
192
193 public static String threadGroupOopGetName(Oop threadGroupOop) {
194 initThreadGroupFields();
195 return stringOopToString(threadGroupNameField.getValue(threadGroupOop));
196 }
197
198 public static Oop[] threadGroupOopGetThreads(Oop threadGroupOop) {
199 initThreadGroupFields();
200 int nthreads = threadGroupNThreadsField.getValue(threadGroupOop);
201 Oop[] result = new Oop[nthreads];
202 ObjArray threads = (ObjArray) threadGroupThreadsField.getValue(threadGroupOop);
203 for (int i = 0; i < nthreads; i++) {
204 result[i] = threads.getObjAt(i);
205 }
206 return result;
207 }
208
209 public static Oop[] threadGroupOopGetGroups(Oop threadGroupOop) {
210 initThreadGroupFields();
211 int ngroups = threadGroupNGroupsField.getValue(threadGroupOop);
212 Oop[] result = new Oop[ngroups];
213 ObjArray groups = (ObjArray) threadGroupGroupsField.getValue(threadGroupOop);
214 for (int i = 0; i < ngroups; i++) {
215 result[i] = groups.getObjAt(i);
216 }
217 return result;
218 }
219
220 private static void initThreadFields() {
221 if (threadNameField == null) {
222 SystemDictionary sysDict = VM.getVM().getSystemDictionary();
223 InstanceKlass k = sysDict.getThreadKlass();
224 threadNameField = (OopField) k.findField("name", "Ljava/lang/String;");
225 threadGroupField = (OopField) k.findField("group", "Ljava/lang/ThreadGroup;");
226 threadEETopField = (LongField) k.findField("eetop", "J");
227 threadTIDField = (LongField) k.findField("tid", "J");
228 threadStatusField = (IntField) k.findField("threadStatus", "I");
229 threadParkBlockerField = (OopField) k.findField("parkBlocker",
230 "Ljava/lang/Object;");
231 TypeDataBase db = VM.getVM().getTypeDataBase();
232 THREAD_STATUS_NEW = db.lookupIntConstant("java_lang_Thread::NEW").intValue();
233 /*
234 Other enum constants are not needed as of now. Uncomment these as and when needed.
235
236 THREAD_STATUS_RUNNABLE = db.lookupIntConstant("java_lang_Thread::RUNNABLE").intValue();
237 THREAD_STATUS_SLEEPING = db.lookupIntConstant("java_lang_Thread::SLEEPING").intValue();
238 THREAD_STATUS_IN_OBJECT_WAIT = db.lookupIntConstant("java_lang_Thread::IN_OBJECT_WAIT").intValue();
239 THREAD_STATUS_IN_OBJECT_WAIT_TIMED = db.lookupIntConstant("java_lang_Thread::IN_OBJECT_WAIT_TIMED").intValue();
240 THREAD_STATUS_PARKED = db.lookupIntConstant("java_lang_Thread::PARKED").intValue();
241 THREAD_STATUS_PARKED_TIMED = db.lookupIntConstant("java_lang_Thread::PARKED_TIMED").intValue();
242 THREAD_STATUS_BLOCKED_ON_MONITOR_ENTER = db.lookupIntConstant("java_lang_Thread::BLOCKED_ON_MONITOR_ENTER").intValue();
243 THREAD_STATUS_TERMINATED = db.lookupIntConstant("java_lang_Thread::TERMINATED").intValue();
244 */
245
246 if (Assert.ASSERTS_ENABLED) {
247 // it is okay to miss threadStatusField, because this was
248 // introduced only in 1.5 JDK.
249 Assert.that(threadNameField != null &&
250 threadGroupField != null &&
251 threadEETopField != null, "must find all java.lang.Thread fields");
252 }
253 }
254 }
255
256 public static Oop threadOopGetThreadGroup(Oop threadOop) {
257 initThreadFields();
258 return threadGroupField.getValue(threadOop);
259 }
260
261 public static String threadOopGetName(Oop threadOop) {
262 initThreadFields();
263 return stringOopToString(threadNameField.getValue(threadOop));
264 }
265
266 /** May return null if, e.g., thread was not started */
267 public static JavaThread threadOopGetJavaThread(Oop threadOop) {
268 initThreadFields();
269 Address addr = threadOop.getHandle().getAddressAt(threadEETopField.getOffset());
270 if (addr == null) {
271 return null;
272 }
273 return VM.getVM().getThreads().createJavaThreadWrapper(addr);
274 }
275
276 public static long threadOopGetTID(Oop threadOop) {
277 initThreadFields();
278 if (threadTIDField != null) {
279 return threadTIDField.getValue(threadOop);
280 } else {
281 return 0;
282 }
283 }
284
285 /** returns value of java.lang.Thread.threadStatus field */
286 public static int threadOopGetThreadStatus(Oop threadOop) {
287 initThreadFields();
288 // The threadStatus is only present starting in 1.5
289 if (threadStatusField != null) {
290 return (int) threadStatusField.getValue(threadOop);
291 } else {
292 // All we can easily figure out is if it is alive, but that is
293 // enough info for a valid unknown status.
294 JavaThread thr = threadOopGetJavaThread(threadOop);
295 if (thr == null) {
296 // the thread hasn't run yet or is in the process of exiting
297 return THREAD_STATUS_NEW;
298 } else {
299 return JVMTI_THREAD_STATE_ALIVE;
300 }
301 }
302 }
303
304 /** returns value of java.lang.Thread.parkBlocker field */
305 public static Oop threadOopGetParkBlocker(Oop threadOop) {
306 initThreadFields();
307 if (threadParkBlockerField != null) {
308 return threadParkBlockerField.getValue(threadOop);
309 }
310 return null;
311 }
312
313 // initialize fields for j.u.c.l AbstractOwnableSynchornizer class
314 private static void initAbsOwnSyncFields() {
315 if (absOwnSyncOwnerThreadField == null) {
316 SystemDictionary sysDict = VM.getVM().getSystemDictionary();
317 InstanceKlass k = sysDict.getAbstractOwnableSynchronizerKlass();
318 absOwnSyncOwnerThreadField =
319 (OopField) k.findField("exclusiveOwnerThread",
320 "Ljava/lang/Thread;");
321 }
322 }
323
324 // return exclusiveOwnerThread field of AbstractOwnableSynchronizer class
325 public static Oop abstractOwnableSynchronizerGetOwnerThread(Oop oop) {
326 initAbsOwnSyncFields();
327 if (absOwnSyncOwnerThreadField == null) {
328 return null; // pre-1.6 VM?
329 } else {
330 return absOwnSyncOwnerThreadField.getValue(oop);
331 }
332 }
333 }