jms modular input app - mixed key value and json event data

I am using the jms modular input app v1.5, and have configured it to successfully read from the queue. But the events have a mixed format - jms header as key value and jms body as json. I understand that in order to achieve index time json extraction, I need to write a cusotm handler to output the body (json) only. So, I have copied this example of PayloadOnlyMessageHandler (assuming it should work for json): https://gist.github.com/damiendallimore/eef6434b8daec578c42a The code doesn't compile becase the return type of handleMessage is void and not Stream. I am using the jmsmodinput.jar downloaded with the app. Can you please assist me with this? Thanks,