Is it possible to reuse a job that is already initialized in memory?

My jobs takes significant time to initialize and am not sure if I can avoid this overhead of initialization each time it is called from java and instead use previously in memory job objects. My requirement is to modify some portion of jobmeta per call and reuse remaining jobmeta info from previously initialized job in memory. I was exploring to use "carteObjectId" and some other API viz. "startJob" to facilitate this but didn't find a suitable API that will enable resetting the jobmeta.