how to figure out whether the javaAPP is running before StartJLinkApplication

how to figure out whether the javaAPP is running before StartJLinkApplication？

I want to execute the task registered in javaApp.

I use  jlink to StartJLinkApplication ,but I dont know whether the app is running .If running will get error such as

XToolkitInUse

Then can not get the handle of JLinkApplication. Is there a way to get the handle app running? Can  invoke the task in runed jlink application