UDF question - how detect a non existing sender element

Question

Hi all,
i have a question according UDF. I have a sender message that contains a field, that sometimes has a content ans some time not. If no content then als the element doesn't exists (occurrence 0...1). The target element of this one has the occurrence status 1.
So i have to create a function, that writes an empty string in case of no sender element. I know that i can configure this function with the MM Blocks (if exists ...). But for re-using reasons i'd like to create a UDF for this function.
Now my question, how can i detect if no data in the sender (src) file?
Here my try, which doesn't works:
AbstractTrace trace = container.getTrace();
trace.addInfo("container: "container);+
trace.addInfo("iData: "iData);+
if(iData == null){
+     trace.addInfo("NO ELEMENT found!");+
if(container == null){
+     trace.addInfo("NO container found!");+
if(iData.length() < 1){
+     trace.addInfo("Empty or No element found - insert empty entry (space)");+
+     return " ";+
return iData;
Thanks in advance
Michael

Answer 1

Hi Michael,
Create a UDF of type value,
Suppose in is the input and out is output of UDF..
Then Code as follows:
if(in==null)
   out = " Empty String Found ";
else
   out = in ;
return out;
Use this code...and get ur problem solved!!!
Regards,
AshwinM
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