How to trouble shoot deadlock

[Durga Krishna]

Hi friends,

If a deadlock happens in my application,
how can I identify which class/object and due to which method it has been locked?

Basically I need to know how to trouble shoot deadlock. Where should I start from?

[Istvan Kovacs]

If running a the console, try Ctrl + Break, it will produce a thread dump that shows what's locked - it will even show what threads and objects are involved.
In a debugger, you can suspend the application - for Eclipse:
http://runnerwhocodes.blogspot.com/2007/10/deadlock-detection-with-eclipse.html

You can also use JConsole.
Other ways (send Unix signal etc.):
http://stackoverflow.com/questions/217113/deadlock-in-java
http://wiki.eclipse.org/How_to_report_a_deadlock

[Durga Krishna]

Thanks for the reply.

But, my application is in production. I want to check due to which class/Method deadlock has occured.
I am using JBoss Application server.
How can I do this?

Thanks in Advance.

[Istvan Kovacs]

Durga Krishna wrote:Thanks for the reply.

But, my application is in production. I want to check due to which class/Method deadlock has occured.
I am using JBoss Application server.
How can I do this?

Thanks in Advance.

Connect to it using JConsole.
Or, on Unix/Linux, send signal 3 and check the output (probably in a log).
Ctrl+Break does not stop the application, BTW.