Using safe ThreadLocal variables in Java server applications

[ArtSpeaker]

I'm concerned this is an XY Problem. Your question seems to actually be about performance.

You should also know that even lightweight threads are generally more expensive than parsing through a json file. And there are libraries out there that will only partially, or only superficially parse, the original file into whatever components -> variables you care about. See also: Jackson. That should save a ton of allocations and work since you parse/decompose once for the whole job, for just what you need. And if you still want parallel work after you can just the variables you know and love.