[vtkusers] VTK and Java Wrappers

[Lars Matthäus]

Works for me! Good job!!

Lars

> Yes, I am working off of CVS head now. I want to avoid the global lock
> solution because this makes it impossible to do VTK processing on
> worker threads in parallel. It should be completely safe to work with
> disjoint sets of VTK objects (i.e. the sets have no references to each
> other) in separate threads. I am aware of at least one person who has
> done this in Java, and a global lock would make the worker threads
> useless, since only one can be working at a time.
> 
> Now, on to the crashes. It can be traced to the fact that the default
> behavior was to call GC() once every second on the event thread. Since
> TestVTKgc.java works on the main thread, this has potential race
> conditions between the main thread and the event thread. In fact,
> making this the default puts us in the same situation as before,
> except instead of conflicts between the main thread and finalizer
> thread, we have conflicts between the main thread and the event
> thread. If you do all your VTK processing on the event thread, this
> default will do what you want.
> 
> Anyway, I just changed the default so you have to explicitly turn on
> automatic garbage collection on the event thread if you want it with:
> 
> vtkGlobalJavaHash.GarbageCollector.SetAutoGarbageCollection(true);
> 
> You should only do this if all VTK processing is done on the event
> thread. If that is not the case, you should manually call
> vtkGlobalJavaHash.GC() at intervals in your program.