exception handling in webdynpro

[Former Member]

hi!

we have a project architechture where webdynpro communicates with session beans.how can we perform exception handling in webdynpro.how do we show the exception in the UI.like an alert or something saying that this is an exception.

i am also unable to find the log file for viewing the details of an exception. where can i find the log file or how do i see a log file for an exception in webdnpro.

thanks in advance,

harish.

[Former Member]

HI! SAM!

can you please tell me the path in WEBDYNPRO where can i find the "IWD Window Manager" and also "IWD Message Manager."i hope these would be required.i could not find them in webynpro environment

thenks in advance,

harish.

[Former Member]

Hi Harish,

both references are reachable using the wdComponentAPI member variable in a controller:

IWDWindowManager winMan = wdComponentAPI.getWindowManager();
IWDMessageManager msgMan = wdComponentAPI.getMessageManager();

Hope that helps.

Regards

Stefan

[Former Member]

Harish,

Did it work?

Thanks,

Sam

[Former Member]

hi!Bertram!

Thanks for the reply.

But,our objective is to make the back end perform some validations and communicate with webdynpro and show the exceptions that arise due to invalid access or something like that which tell the user that he cannot perform the action and proceed further as his request is not valid.

these validations are performed in the backend(R/3) system and the result of the validation should be shown to the user in the webdynpro.

<b>this is our scenario:</b>

1. User/Initiator selects the PO Items for collaboration on the Inquiry UI Screen.

2. User clicks on the “Collab” button.

3. Validate if the Line Items selected are valid for collaboration. A selected Line Item is not valid for collaboration if:-

(i) It is already in collaboration. i.e the status of the Line item is marked “In Collaboration”

(ii) Item has been cancelled.

(iii) Event Management Status prevents collaboration.

<i><b>This validation is performed by a call from UI to the Services layer. Application Service – POCollaborationService -> Method: GetCurrentPODetails

If any of the items are not valid then an exception is raised and an error mes-sage will be displayed in the UI. The user than can unselect the invalid items and continue or cancel.</b></i>

please advise as of how to make the back end tell UI that there is an exception and prevent the user from proceeding further until he unselects some items which he cannot change or access

thanks in advance,

harish

[Former Member]

Hi Harish,

If the backend is R/3, I don't think you might not have to interact with session beans. Instead you could use JCO to hook to the r/3 system. If the exception is a validation error, I assume it would be and export parameter or a table of the calling BAPI. Instead if the error is because of the connection , JCO could handle it and you can get access to the JCO exception in your web dynpro code.

In order to display the error, you could use Error handling features of Web Dynpro. If you are specific about some functionality like alert button, your could user "createConfirmationWindow" of "IWDWindowManager".

[BeGanz]

Hallo Harish,

look at Sample Application 'Error Messages and Error Support' (https://www.sdn.sap.com/sdn/developerareas/webdynpro.sdn?page=TutWD3_MessageErrorSupport.htm). You can find it in the 'Web Dynpro Sample Applications and Tutorials' section containing the Web Dynpro feature-to-sample-matrix.(https://www.sdn.sap.com/sdn/developerareas/webdynpro.sdn?page=webdynpro_tutorials.htm).

In addtion the NetWeaver Help contains a special section dealing with this topic: 'Web Dynpro'-'The Development Process' - 'Error Handling'.

You can easily find the relevant NetWeaver Help information by utilizing the sophisticated SDN search functionality: in the search form at the left side type in 'Web Dynpro Error Handling' and select 'help.sap.com' in the dropdown listbox.

The default trace file of your SAP J2EE Engine is stored in <Drive>\usr\sap\<System ID>\JC00\j2ee\cluster\server0\log with the name 'defaultTrace.trc.0'.

Greetings, Bertram