On 11.2.2014 16:31, shanliang wrote:
Staffan Larsen wrote:
Hi Shanliang,
I can’t quite see how the test can fail in this way. When the
ClassPrepareEvent happens, the debuggee will be suspended. So when
addFieldWatch() is called, the debuggee should not have moved.
I am not expert of jdi so I may miss something here. I checked the
failure trace and saw the report exception happen when FieldMonitor
received ClassPrepareEvent and was doing addFieldWatch. FieldMonitor did
call "vm.resume()" before treating events.
AFAICS, calling vm.resume() results in an almost immediate debuggee
death. The gc() invoking thread "d" is flagged as a deamon and as such
doesn't prevent the process from exiting. The other thread is not a
daemon but will finish in only few cycles.
I reproduced the bug by add sleep(1000) after vm.resume() but before
calling eventQueue.remove();
It looks like some kind of synchronization between the debugger and the
debuggee is necessary. But I wonder if you should better use the
process.getOuptuptStream() to write and flush a message for the debugee
indicating that it can exit. And in the debugee you would just do
System.in.read() as the last statement in the main() method. Seems more
robust than involving files.
Cheers,
-JB-
Thanks,
Shanliang
One problem I do see with the test is that it does not wait for a
VMStartEvent before setting up requests. I’m not sure if that could
cause the failure in the bug report, though.
/Staffan
On 11 feb 2014, at 15:13, shanliang <shanliang.ji...@oracle.com> wrote:
Hi ,
The problem could be that FieldMonitor did not have enough time to
"addFieldWatch" but the vm to monitor (TestPostFieldModification) was
already ended.
So we should make sure that TestPostFieldModification exits after
FieldMonitor has done necessary. The solution proposed here is that
FieldMonitor creates a file after adding field watching, and
TestPostFieldModification quits only after finding the file.
web:
http://icncweb.fr.oracle.com/~shjiang/webrev/8007710/00/
bug:
https://bugs.openjdk.java.net/browse/JDK-8007710
Thanks,
Shanliang
