getDocument() from a XSPDocument is null randomly

Question

In a production application that I have developed sometimes I get an error saying .getDocument() is null. I have added checks in my code that traps an error if this happens. And the strange thing is that the XSPDocument seams to be OK.

Any other ideas how to debug the cause of this?

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The lower parts of the application is a simple database, create an assignment it gets status new change the status to ongoing thru a button. Add information in text, date and numberfields, no Richtext, no attachments.

The user can switch to another xpage to send this document is an pdf attachment in an email.

The user can save the document as a draft

When they are done the click on an approve button and this button will set the status to approved. Save the document and send it as an pdf to an email adress

The problem ocurrs both on the Save button and on the approve button.

.getDocument from the xsp document is null the xspdocument.getNoteID return an ID I can do replaceitemvalue on the xsp document. It never happens on new documents only existing what I have seen

It feels like the comment from David that the backend doc is dropped/recycled

No reader fields in the app and the document opens up and the user works with the document. But sometimes when saving or preforming some tasks this happends — Fredrik Norling, Mar 11 '13 at 16:46

score 0 · Answer 1 · answered Mar 12 '13 at 07:05

Hard to give a hint without knowing more about everything else, but I remember having seen this as well. Just a few ideas: Is XSPDocument.getNoteID() pointing to a valid Document if this happens? Is it maybe pointing to a different doc than what you expected? Could there be some kind of dynamic change of datasources going on? Maybe some kind of timeout so that the server all of a sudden forgot who you are (in rare cases this happens to me)? Lothar/edcom

score 0 · Accepted Answer · answered Mar 12 '13 at 12:19

we experienced the same getDocument() problem recently. Finally we found a root cause: two different XPages were loaded simultaneously via iFrames. One of those XPages produced run-time error randomly, in 25% of cases. A sort of conflict in JSF model in context of single session.

solution: viewState="nostate"

not sure if it helps in your case, but this option resolved a lot of problems in our applications. It was introduced in 8.5.3. And it should be especially useful for so called XAgents.

I think in an ordinary XPage this might give problems not saving any state. — Fredrik Norling, Mar 14 '13 at 08:14

score 0 · Answer 3 · answered Mar 13 '13 at 17:35

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It would be helpful to have a few more details. I assume that the document has previously been saved and it's not a new note?

You're not trying to put the actual document object inside a scoped variable are you? That would be bad as that would be pretty toxic. Without knowing more I would think this could be the case. The backend document has been garbage collected.

answered Mar 13 '13 at 17:35

David Leedy

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I'll happily add more information but the problem is what to add. ;-) – Fredrik Norling Mar 14 '13 at 07:52

getDocument() from a XSPDocument is null randomly

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3 Answers3