It seems you (or your team) are developing this Java app. Why don't you send JSON instead of custom strings joined by &?
You would have solved this days ago. No string splitting, data values & topics available with zero effort.
Do you understand what the benefit of sending JSON offers? Do you understand what JSON is?
Lastly, if you absolutely MUST use this custom strings format, please show me 2 demo strings and how they should look after the function node.
E.g. xyz&124 should send { "topic" : 124 }
Ps, to copy the string exactly as it appears in the debug window, use the "copy value" button that appears under your mouse when you hover over the value in the debug window.
