J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2004 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 21 | * have any questions. |
| 22 | */ |
| 23 | |
| 24 | /* |
| 25 | * @test |
| 26 | * @bug 4530538 |
| 27 | * @summary Basic unit test of ThreadInfo.getStackTrace() and |
| 28 | * ThreadInfo.getThreadState() |
| 29 | * @author Mandy Chung |
| 30 | * |
| 31 | * @run build Semaphore |
| 32 | * @run main ThreadStackTrace |
| 33 | */ |
| 34 | |
| 35 | import java.lang.management.*; |
| 36 | |
| 37 | public class ThreadStackTrace { |
| 38 | private static ThreadMXBean mbean |
| 39 | = ManagementFactory.getThreadMXBean(); |
| 40 | private static boolean notified = false; |
| 41 | private static Object lockA = new Object(); |
| 42 | private static Object lockB = new Object(); |
| 43 | private static volatile boolean testFailed = false; |
| 44 | private static String[] blockedStack = {"run", "test", "A", "B", "C", "D"}; |
| 45 | private static int bsDepth = 6; |
| 46 | private static int methodB = 4; |
| 47 | private static String[] examinerStack = {"run", "examine1", "examine2"}; |
| 48 | private static int esDepth = 3; |
| 49 | private static int methodExamine1= 2; |
| 50 | |
| 51 | private static void goSleep(long ms) { |
| 52 | try { |
| 53 | Thread.sleep(ms); |
| 54 | } catch (InterruptedException e) { |
| 55 | e.printStackTrace(); |
| 56 | System.out.println("Unexpected exception."); |
| 57 | testFailed = true; |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | private static void checkNullThreadInfo(Thread t) throws Exception { |
| 62 | ThreadInfo ti = mbean.getThreadInfo(t.getId()); |
| 63 | if (ti != null) { |
| 64 | ThreadInfo info = |
| 65 | mbean.getThreadInfo(t.getId(), Integer.MAX_VALUE); |
| 66 | System.out.println(INDENT + "TEST FAILED:"); |
| 67 | if (info != null) { |
| 68 | printStack(t, info.getStackTrace()); |
| 69 | System.out.println(INDENT + "Thread state: " + info.getThreadState()); |
| 70 | } |
| 71 | throw new RuntimeException("TEST FAILED: " + |
| 72 | "getThreadInfo() is expected to return null for " + t); |
| 73 | } |
| 74 | } |
| 75 | |
| 76 | private static boolean trace = false; |
| 77 | public static void main(String args[]) throws Exception { |
| 78 | if (args.length > 0 && args[0].equals("trace")) { |
| 79 | trace = true; |
| 80 | } |
| 81 | |
| 82 | Examiner examiner = new Examiner("Examiner"); |
| 83 | BlockedThread blocked = new BlockedThread("BlockedThread"); |
| 84 | examiner.setThread(blocked); |
| 85 | |
| 86 | checkNullThreadInfo(examiner); |
| 87 | checkNullThreadInfo(blocked); |
| 88 | |
| 89 | // Start the threads and check them in Blocked and Waiting states |
| 90 | examiner.start(); |
| 91 | |
| 92 | // block until examiner begins doing its real work |
| 93 | examiner.waitForStarted(); |
| 94 | |
| 95 | System.out.println("Checking stack trace for the examiner thread " + |
| 96 | "is waiting to begin."); |
| 97 | |
| 98 | // The Examiner should be waiting to be notified by the BlockedThread |
| 99 | checkThreadState(examiner, Thread.State.WAITING); |
| 100 | |
| 101 | // Check that the stack is returned correctly for a new thread |
| 102 | checkStack(examiner, examinerStack, esDepth); |
| 103 | |
| 104 | System.out.println("Now starting the blocked thread"); |
| 105 | blocked.start(); |
| 106 | |
| 107 | try { |
| 108 | examiner.join(); |
| 109 | blocked.join(); |
| 110 | } catch (InterruptedException e) { |
| 111 | e.printStackTrace(); |
| 112 | System.out.println("Unexpected exception."); |
| 113 | testFailed = true; |
| 114 | } |
| 115 | |
| 116 | // Check that the stack is returned correctly for a terminated thread |
| 117 | checkNullThreadInfo(examiner); |
| 118 | checkNullThreadInfo(blocked); |
| 119 | |
| 120 | if (testFailed) |
| 121 | throw new RuntimeException("TEST FAILED."); |
| 122 | |
| 123 | System.out.println("Test passed."); |
| 124 | } |
| 125 | |
| 126 | private static String INDENT = " "; |
| 127 | private static void printStack(Thread t, StackTraceElement[] stack) { |
| 128 | System.out.println(INDENT + t + |
| 129 | " stack: (length = " + stack.length + ")"); |
| 130 | if (t != null) { |
| 131 | for (int j = 0; j < stack.length; j++) { |
| 132 | System.out.println(INDENT + stack[j]); |
| 133 | } |
| 134 | System.out.println(); |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | private static void checkThreadState(Thread thread, Thread.State s) |
| 139 | throws Exception { |
| 140 | |
| 141 | ThreadInfo ti = mbean.getThreadInfo(thread.getId()); |
| 142 | if (ti.getThreadState() != s) { |
| 143 | ThreadInfo info = |
| 144 | mbean.getThreadInfo(thread.getId(), Integer.MAX_VALUE); |
| 145 | System.out.println(INDENT + "TEST FAILED:"); |
| 146 | printStack(thread, info.getStackTrace()); |
| 147 | System.out.println(INDENT + "Thread state: " + info.getThreadState()); |
| 148 | |
| 149 | throw new RuntimeException("TEST FAILED: " + |
| 150 | "Thread state for " + thread + " returns " + ti.getThreadState() + |
| 151 | ". Expected to be " + s); |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | private static void checkThreadState(Thread thread, |
| 156 | Thread.State s1, Thread.State s2) |
| 157 | throws Exception { |
| 158 | |
| 159 | ThreadInfo ti = mbean.getThreadInfo(thread.getId()); |
| 160 | if (ti.getThreadState() != s1 && ti.getThreadState() != s2) { |
| 161 | throw new RuntimeException("TEST FAILED: " + |
| 162 | "Thread state for " + thread + " returns " + ti.getThreadState() + |
| 163 | ". Expected to be " + s1 + " or " + s2); |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | private static void checkStack(Thread t, String[] expectedStack, |
| 168 | int depth) throws Exception { |
| 169 | ThreadInfo ti = mbean.getThreadInfo(t.getId(), Integer.MAX_VALUE); |
| 170 | StackTraceElement[] stack = ti.getStackTrace(); |
| 171 | |
| 172 | if (trace) { |
| 173 | printStack(t, stack); |
| 174 | } |
| 175 | int frame = stack.length - 1; |
| 176 | for (int i = 0; i < depth; i++) { |
| 177 | if (! stack[frame].getMethodName().equals(expectedStack[i])) { |
| 178 | throw new RuntimeException("TEST FAILED: " + |
| 179 | "Expected " + expectedStack[i] + " in frame " + frame + |
| 180 | " but got " + stack[frame].getMethodName()); |
| 181 | } |
| 182 | frame--; |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | static class BlockedThread extends Thread { |
| 187 | private Semaphore handshake = new Semaphore(); |
| 188 | |
| 189 | BlockedThread(String name) { |
| 190 | super(name); |
| 191 | } |
| 192 | boolean hasWaitersForBlocked() { |
| 193 | return (handshake.getWaiterCount() > 0); |
| 194 | } |
| 195 | |
| 196 | void waitUntilBlocked() { |
| 197 | handshake.semaP(); |
| 198 | |
| 199 | // give a chance for the examiner thread to really wait |
| 200 | goSleep(20); |
| 201 | } |
| 202 | |
| 203 | void waitUntilLockAReleased() { |
| 204 | handshake.semaP(); |
| 205 | |
| 206 | // give a chance for the examiner thread to really wait |
| 207 | goSleep(50); |
| 208 | } |
| 209 | |
| 210 | private void notifyWaiter() { |
| 211 | // wait until the examiner waits on the semaphore |
| 212 | while (handshake.getWaiterCount() == 0) { |
| 213 | goSleep(20); |
| 214 | } |
| 215 | handshake.semaV(); |
| 216 | } |
| 217 | |
| 218 | private void test() { |
| 219 | A(); |
| 220 | } |
| 221 | private void A() { |
| 222 | B(); |
| 223 | } |
| 224 | private void B() { |
| 225 | C(); |
| 226 | |
| 227 | // notify the examiner about to block on lockB |
| 228 | notifyWaiter(); |
| 229 | |
| 230 | synchronized (lockB) { |
| 231 | }; |
| 232 | } |
| 233 | private void C() { |
| 234 | D(); |
| 235 | } |
| 236 | private void D() { |
| 237 | // Notify that examiner about to enter lockA |
| 238 | notifyWaiter(); |
| 239 | |
| 240 | synchronized (lockA) { |
| 241 | notified = false; |
| 242 | while (!notified) { |
| 243 | try { |
| 244 | // notify the examiner about to release lockA |
| 245 | notifyWaiter(); |
| 246 | // Wait and let examiner thread check the mbean |
| 247 | lockA.wait(); |
| 248 | } catch (InterruptedException e) { |
| 249 | e.printStackTrace(); |
| 250 | System.out.println("Unexpected exception."); |
| 251 | testFailed = true; |
| 252 | } |
| 253 | } |
| 254 | System.out.println("BlockedThread notified"); |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | public void run() { |
| 259 | test(); |
| 260 | } // run() |
| 261 | } // BlockedThread |
| 262 | |
| 263 | static class Examiner extends Thread { |
| 264 | private static BlockedThread blockedThread; |
| 265 | private Semaphore handshake = new Semaphore(); |
| 266 | |
| 267 | Examiner(String name) { |
| 268 | super(name); |
| 269 | } |
| 270 | |
| 271 | public void setThread(BlockedThread thread) { |
| 272 | blockedThread = thread; |
| 273 | } |
| 274 | |
| 275 | public synchronized void waitForStarted() { |
| 276 | // wait until the examiner is about to block |
| 277 | handshake.semaP(); |
| 278 | |
| 279 | // wait until the examiner is waiting for blockedThread's notification |
| 280 | while (!blockedThread.hasWaitersForBlocked()) { |
| 281 | goSleep(50); |
| 282 | } |
| 283 | // give a chance for the examiner thread to really wait |
| 284 | goSleep(20); |
| 285 | } |
| 286 | |
| 287 | private Thread itself; |
| 288 | private void examine1() { |
| 289 | synchronized (lockB) { |
| 290 | examine2(); |
| 291 | try { |
| 292 | System.out.println("Checking examiner's its own stack trace"); |
| 293 | checkThreadState(itself, Thread.State.RUNNABLE); |
| 294 | checkStack(itself, examinerStack, methodExamine1); |
| 295 | |
| 296 | // wait until blockedThread is blocked on lockB |
| 297 | blockedThread.waitUntilBlocked(); |
| 298 | |
| 299 | System.out.println("Checking stack trace for " + |
| 300 | "BlockedThread - should be blocked on lockB."); |
| 301 | checkThreadState(blockedThread, Thread.State.BLOCKED); |
| 302 | checkStack(blockedThread, blockedStack, methodB); |
| 303 | } catch (Exception e) { |
| 304 | e.printStackTrace(); |
| 305 | System.out.println("Unexpected exception."); |
| 306 | testFailed = true; |
| 307 | } |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | private void examine2() { |
| 312 | synchronized (lockA) { |
| 313 | // wait until main thread gets signalled of the semaphore |
| 314 | while (handshake.getWaiterCount() == 0) { |
| 315 | goSleep(20); |
| 316 | } |
| 317 | |
| 318 | handshake.semaV(); // notify the main thread |
| 319 | try { |
| 320 | // Wait until BlockedThread is about to block on lockA |
| 321 | blockedThread.waitUntilBlocked(); |
| 322 | |
| 323 | System.out.println("Checking examiner's its own stack trace"); |
| 324 | checkThreadState(itself, Thread.State.RUNNABLE); |
| 325 | checkStack(itself, examinerStack, esDepth); |
| 326 | |
| 327 | System.out.println("Checking stack trace for " + |
| 328 | "BlockedThread - should be blocked on lockA."); |
| 329 | checkThreadState(blockedThread, Thread.State.BLOCKED); |
| 330 | checkStack(blockedThread, blockedStack, bsDepth); |
| 331 | |
| 332 | } catch (Exception e) { |
| 333 | e.printStackTrace(); |
| 334 | System.out.println("Unexpected exception."); |
| 335 | testFailed = true; |
| 336 | } |
| 337 | } |
| 338 | |
| 339 | // release lockA and let BlockedThread to get the lock |
| 340 | // and wait on lockA |
| 341 | blockedThread.waitUntilLockAReleased(); |
| 342 | |
| 343 | synchronized (lockA) { |
| 344 | try { |
| 345 | System.out.println("Checking stack trace for " + |
| 346 | "BlockedThread - should be waiting on lockA."); |
| 347 | checkThreadState(blockedThread, Thread.State.WAITING); |
| 348 | checkStack(blockedThread, blockedStack, bsDepth); |
| 349 | |
| 350 | // Let the blocked thread go |
| 351 | notified = true; |
| 352 | lockA.notify(); |
| 353 | } catch (Exception e) { |
| 354 | e.printStackTrace(); |
| 355 | System.out.println("Unexpected exception."); |
| 356 | testFailed = true; |
| 357 | } |
| 358 | } |
| 359 | // give some time for BlockedThread to proceed |
| 360 | goSleep(50); |
| 361 | } // examine2() |
| 362 | |
| 363 | public void run() { |
| 364 | itself = Thread.currentThread(); |
| 365 | examine1(); |
| 366 | } // run() |
| 367 | } // Examiner |
| 368 | } |