Testing Restful services with Jmeter

Outside of Transaction Controllers, regular expressions and xpath extractors are probably used frequently in your scripts.  Sometimes you have the need to collect multiple variables from one or more responses and store them in one variable that will become a data parameter in a subsequent request.
Generally if you read through Jmeter User Group threads you’ll see lots of people trying to do this or at least asking how do I store variables in an array type of data structure.
In order to do this