Before we try to solve the code snippet... Can you tell us why you need to change the last digit of the incoming URLPARAM0 from 'w' to 'Z'? Is there some reason the URLPARAM0 Comparison Operator and Value in the VSI can not handle a regex to accept both values or map the key ending with "Z" to the specific transaction ending with "w"?
I believe the logic is syntactically incorrect. setArguments() has no signature to accept a String as input.
Using the SDK - DevTest Solutions - 10.1 - CA Technologies Documentation
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Look in the "doc" directory in your installation folder for an examples.zip file.
Navigate to com/itko/util/ParameterList and review constructor, containsKey, get, put, and addParameters methods.
_logger.debug(" ") only outputs if logging.properties is set to DEBUG. _logger.info("") will display lines in the log if logging.properties is set to INFO. INFO will also place an entry in the Events tab in ITR.
The lisa_vse_request.setArguments() methods needs a ParameterList so you need to convert the String.
The key/value pairs in the String need to be delimited by '&'.
The ParameterList constructor can use the String as input. (e.g., "key1=value1&key2=value2")
No need to return lisa_vse_request as it is globally available, but you could return valueToAdd which would set LASTRESPONSE for you.