Mapping Exception during Dynamic file configuration

Question

Hello,
I have to configure the file adapter such that the file name is configured dynamically.
I wrote a UDF which gives the following error.
<SAP:Stack>com.sap.aii.utilxi.misc.api.BaseRuntimeException thrown during application mapping com/sap/xi/tf/_GSFt_AccountReconciliation_Format_: RuntimeException in Message-Mapping transformatio</SAP:Stack>
  <SAP:Retry>M</SAP:Retry>
  </SAP:Error>
The code is :
DynamicConfiguration conf = (DynamicConfiguration)
container.getTransformationParameters().get(StreamTransformationConstants.DYNAMIC_CONFIGURATION);
DynamicConfigurationKey key = DynamicConfigurationKey.create("http//sap.com/xi/XI/System/File","FileName");
String FileName  = conf.get(key);
String newFN = FileName.substring (11,15) ;
String FN = "<abc>+  newFN +  "_"  +    ".dat";
conf.put(key,FN);
return FN;
Am I missing something here?
I have also specified the variable substitution in Receiver Channel.
Kindly help me out ppl.
Regards,
Sanjay

Answer 1

Modify code as below...
String FN="";
try{
DynamicConfiguration conf = (DynamicConfiguration)
container.getTransformationParameters().get(StreamTransformationConstants.DYNAMIC_CONFIGURATION);
DynamicConfigurationKey key = DynamicConfigurationKey.create("http//sap.com/xi/XI/System/File","FileName");
String FileName = conf.get(key);
if(FileName != null && FileName !=""){
String newFN = FileName.substring (11,15) ;  //make sure u do substring rite way... index 10 is 11th char of the string
FN = "<abc>+ newFN + "_" + ".dat";
conf.put(key,FN);
}catch{
return FN;