500 Internal Server Error in webdynpro

[Former Member]

Hi all,

i am getting the following error when i tested the application in QAE.

The error stack trace is

com.sap.tc.webdynpro.services.session.LockException: Thread SAPEngine_Application_Thread[impl:3]_14 failed to acquire exclusive lock on client session ClientSession(. m e l at com.sap.tc.webdynpro.clientserver.session.ClientSession$LockingManager.lock(ClientSession.java:1511)

at com.sap.tc.webdynpro.clientserver.session.ClientSession.doProcessing(ClientSession.java:233)

at com.sap.tc.webdynpro.clientserver.session.RequestManager.doProcessing(RequestManager.java:150)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doContent(DispatcherServlet.java:62)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doPost(DispatcherServlet.java:53)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)

Regards

ChandraShekar

[Former Member]

Hi,

500 internal error is coming mostly for the NULL values. Try to check the values that you are using for session and for other operation.

But the LockException is a result of may be your refresh-operation (maybe with session-data of your previous run of the webdynpro-application in your browser)

Hope that will help you.

Regards,

Deepak

[Former Member]

Hi Deepak,

It is working fine at the client side.In QAE this problem is comming...

Is it that the modifications has to be done in the backend R3 level or at the application level to handle this error..

Regards

ChandraShekar

[Former Member]

Hi,

plz try to debug frm the application level first.

Regards,

Deepak

[Former Member]

Hi Deepak,

Actually the Application has been mooved to QAE,when we tested it on our end its working fine,but there at the client side it is giving this exception.

So Debugging at the Application level at this stage is a difficult task,so if an alternative is provided we can work on it.

Any other ideas are welcomed.

Thanks and regards,

Chandrashekar.

[Former Member]

Hi,

As I wrote here [|], the reason for LockException may vary. The LockException itself means that your thread where the Web Dynpro application is running, is waiting for some other thread to complete it's operation. It can be because of synchronized methods used to access shared resource, for example Data Base.

To understand what's going on, make a thread dump right after your got the LockException. In thread dump you can find which thread is blocking your's one SAPEngine_Application_Threadimpl:3_14 and where the block appears (class and line number)

Regards

Ivan