/* * Copyright (c) 2006, 2016, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions.
*/
/* * This debuggee basically runs two threads each of * which loop, hitting a bkpt in each iteration. *
*/ class InvokeHangTarg extendsThread { staticboolean one = false; static String name1 = "Thread 1"; static String name2 = "Thread 2"; staticint count = 100;
publicstaticvoid main(String[] args) {
System.out.println("Howdy!");
InvokeHangTarg t1 = new InvokeHangTarg(name1);
InvokeHangTarg t2 = new InvokeHangTarg(name2);
t1.start();
t2.start();
}
// This is called from the debugger via invokeMethod publicdouble invokeee() {
System.out.println("Debuggee: invokeee in thread "+Thread.currentThread().toString()); Thread.yield(); return longMethod(2);
} publicdouble longMethod(int n) { double a = 0; double s = 0; for (int i = 0; i < n; i++) {
a += i; for (int j = -1000*i; j < 1000*i; j++) {
a = a*(1 + i/(j + 0.5));
s += Math.sin(a);
}
}
System.out.println("Debuggee: invokeee finished"); return s;
}
public InvokeHangTarg(String name) { super(name);
}
// BreakpointEvent handler publicvoid breakpointReached(BreakpointEvent event) { if (bkpts == 0) { /* * This thread will watch for n secs to go by with no * calls to this method.
*/
timerThread.start();
}
synchronized("abc") { /* * Note that this will most likely never get to * the number of times the two bkpt lines in the debuggee * are hit because bkpts are lost while they are disabled.
*/
bkpts++;
}
/* * The bug occurs when the requests are disabled * and then an invoke is done in the event handler. In some cases * the other thread has hit a bkpt and the back-end is waiting * to send it. When the back-end resumes the debuggee to do the * invokeMethod, this 2nd bkpt is released, the debuggee is suspended, including * the thread on which the invoke was done (because it is a SUSPEND_ALL bkpt), * the bkpt is sent to the front-end, but the client event handler is sitting * here waiting for the invoke to finish, so it doesn't get the 2nd bkpt and * do the resume for it. Thus, the debuggee is suspended waiting for a resume * that never comes.
*/
request1.disable();
request2.disable();
ThreadReference thread = event.thread(); try {
StackFrame sf = thread.frame(0);
System.err.println(" Debugger: Breakpoint hit at "+sf.location());
doInvoke(thread, sf.thisObject(), "invokeee");
} catch (IncompatibleThreadStateException itsex) {
itsex.printStackTrace();
failure("failure: Exception");
}
request1.enable();
request2.enable();
}
/********** test core **********/
protectedvoid runTests() throws Exception {
/* * Get to the top of main() * to determine targetClass and mainThread
*/
BreakpointEvent bpe = startToMain("InvokeHangTarg");
targetClass = bpe.location().declaringType();
mainThread = bpe.thread();
EventRequestManager erm = vm().eventRequestManager(); finalThread mainThread = Thread.currentThread();
/* * This thread will be started when we get the first bkpt. * (Which we always expect to get). * It awakens every n seconds and checks to see if we * got any breakpoint events while it was asleep. If not, then * we assume the debuggee is hung and fail the test.
*/
timerThread = newThread("test timer") { publicvoid run() { int myBkpts = bkpts; while (true) { try { Thread.sleep(waitTime);
System.out.println("bkpts = " + bkpts); if (myBkpts == bkpts) { // no bkpt for 'waitTime' msecs
failure("failure: Debuggee appears to be hung");
vmDisconnected = true; // This awakens the main thread which is // waiting for a VMDisconnect.
mainThread.interrupt(); break;
}
myBkpts = bkpts;
} catch (InterruptedException ee) { // If the test completes, this occurs.
println("timer Interrupted"); break;
}
}
}
};
/* * resume the target, listening for events
*/
listenUntilVMDisconnect();
timerThread.interrupt(); /* * deal with results of test * if anything has called failure("foo") testFailed will be true
*/ if (!testFailed) {
println("InvokeHangTest: passed; bkpts = " + bkpts);
} else { thrownew Exception("InvokeHangTest: failed; bkpts = " + bkpts);
}
}
}
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