NullPointer Exception in a tAdvancedFileOutputXML

[Anonymous]

Hi,
I have a similar problem as https://community.talend.com/t5/Design-and-Development/tAdvancedFileOuputXML-not-able-to-use-namespa... but I don't find (understand?) the answer.
Attached to this message, you'll find the job and both tAdvancedFileOutputXML.
In running, I have
"Exception in component tAdvancedFileOutputXML_2
java.lang.NullPointerException"
I've tried with "RefereceDepot" in first tAdvancedFileOutputXML, or not. Same result.
It's the same name of file "copy/paste"
But not the same XML Tree (I've tried with the same).
I don't fint the way to answer...
Thank's for your help.

[Anonymous]

You need an extra element. This XML document is built up row-by-row from reference_depot records. The extra element will represent a reference_depot row and contains the subelements and attributes. "BD" is used for all the rows. The "RD" in this screenshot is the loop element containing a single row.

[Anonymous]

If I set only a loop boucle (as you seem saying), Talend send message "Parameter (XML Loop) must set as loop and set a group at least.".
I've update the two "tAdvancedFileOutputXML", the tree had not the same root. Now they have.
But I always not understand.

[Anonymous]

I've found a solution.
There is now a subjob to write "ReferenceDepot" loop, and one other for "Publication". And now, it's run
Thank you