Error while using the variable name "VARIABLE" in variable substitution

Question

Hi Experts,
  I am using variable substitution to have my output filename set as a payload field value. It is working fine when I am using the variable name as fname, subs etc but channel goes in error when I am using the variable name as "VARIABLE". This is probably a reserved word but i would like to know where i can find a detailed documentation on this. Say things to note / restrictions while using variable substitution.
This is the error in the channel:
Message processing failed. Cause: com.sap.aii.af.ra.ms.api.RecoverableException: Error during variable substitution: java.text.ParseException: Variable 'variable' not found in variable substitution table: com.sap.aii.adapter.file.configuration.DynamicConfigurationException: Error during variable substitution: java.text.ParseException: Variable 'variable' not found in variable substitution table
Thanks,
Diya

Answer 1

Hi Zevik,
Thanks for the reply. The output file is created correctly by merely changing the variable name to something else and hence the doubt.
Below is the configuration:
Variable Substituition
VARIABLE    payload:interface_dummy,1,Recordset,1,Header,1,field1,1
Filename schema : TEST_%VARIABLE%.txt
Output xml structure:
<?xml version="1.0" encoding="utf-8" ?>
- <ns:interface_dummy xmlns:ns="http://training.eu.unilever.com">
- <ns:Recordset xmlns:ns="http://training.eu.unilever.com">
- <Header>
  <identifier>HDR</identifier>
  <field1>001</field1>
  <field2>001</field2>
  <field3>R</field3>
  </Header>
- <Detail>
  <identifier>A</identifier>
  <field1>000000002</field1>
  <field2 />
  <field3>Doretha.Walker</field3>
  </Detail>
I thimk my configuration is correct as it is working correctly with the variable name change, However, maybe i missed something !