Problem in mapping with optional tag

Question

Hi all,
I have to map the following messages:
Source:
<POITEM> (occurrence 0...unbounded)
   <TipoRecord></TipoRecord>
   <PO_ITEM></PO_ITEM>
   <DELETE_IND></DELETE_IND>
</POITEM>
<POITEM>
   <TipoRecord></TipoRecord>
   <PO_ITEM></PO_ITEM>
   <DELETE_IND></DELETE_IND>
</POITEM>
Target:
<POITEM_B> (occurrence 0 1)
    <item>  (occurrence 0...unbounded)
       <TipoRecord></TipoRecord>
       <PO_ITEM></PO_ITEM>
       <DELETE_IND></DELETE_IND>
    </item>
     <item>
        <TipoRecord></TipoRecord>
        <PO_ITEM></PO_ITEM>
        <DELETE_IND></DELETE_IND>
     </item>
</POITEM_B>
To do this mapping I have mapped "POITEM" of the source message with "item" of the target one and in that way the cardinality is ok.
Since POITEM_B is optional, even if there are in the source message <POITEM> elements, the tag <POITEM_B> is not created (nor its children).
So I mapped <POITEM> to <POITEM_B>:
the result is ok only for the first <POITEM> element; the second <POITEM> element generates the tag <POITEM_B> without any tag <item> below!
I have tried in several ways (like changing context, and others), but the only way I have found to get all the correct <item> tags below <POITEM>, is to map <POITEM_B> with a Constant!!!
Someone can suggest me a better solution?
ThankS!
Luciana

Answer 1

Hi Luciana,
when I understand you correct you just want to create the <POITEM_B> and <item> nodes of the target structure if <POITEM> exists. If not, you don't want to create <POITEM_B> and all nodes below, correct?
If so, please try the following:
<POITEM> --> NodeFunction Exists --> NodeFunction collapseContexts  --> NodeFunction createIf --> <POITEM_B>
--> This should generate exactly one <POITEM_B> if 1..n <POITEM> elements exist.
<POITEM> --> <item>
--> This should generate the same number <item> nodes you've <POITEM> nodes
Best regards
Lars