What java process is it that's running? A typical Fedora system doesn't have Java code running very much. The browser will run the plugin for java occasionally.
Running 'jvisualvm' will let you use VisualVM to examine the java vm.
Just run "jvisualvm" from a terminal and
from the Applications page on the left side, pick the entry under the "Local" label that's not VisualVM,
it's likely the only other one in the list and just below it.
With it selected, right mouse click it and pick "Open". Now you should have tabs on the right of the tool showing the "Overview", "Monitor", "Threads", "Sampler" and "Profiler".
Go to the Overview and in the "System properties" the "user.dir" will show you where the java class is running from and "sun.java.command" will be the name of the class.
Another option is:
which will show the stack of the process, only do that if `pgrep java` only shows one pid. From the jstack listing, you can frequently see what the "main" is doing (the main function) and what the class is called (bolded here). Here is the main jstack listing for a simple class I wrote that just sleeps in a thread:
"main" prio=10 tid=0x00007ffabc007800 nid=0x5cc6 waiting on condition [0x00007ffac15f4000]
java.lang.Thread.State: TIMED_WAITING (sleeping)
at java.lang.Thread.sleep(Native Method)
PS. you'll only have jstack and jvisualvm available on your system if you have the JDK installed