Hi Guillaume, Could you turn on debug mode so you can see the source of the NPE? If you are using ant to compile kepler, the debug mode should already be turned on. If you're using javac to compile your code separately, you need to use the -g flag to turn on debugging. This will give you the line number where the NPE is thrown and make it easier to figure out what is going on (so you don't get "Unknown Source" in the stack trace).
My initial hunch is that a parameter or attribute is getting created the first time, but not on the 2nd run for some reason. This happens sometimes in kepler when you try to create an attribute with the same name as one that exists and don't check for it existing. Technically what should happen is that a NameDuplicationException should be thrown, but I've seen the behavior you describe also. chad tog wrote: > Dear all, > > I have the following error when trying to re-execute a workflow: > > java.lang.NullPointerException > at org.gridle.plugin.kepler.component.OutputPlug.fire(Unknown Source) > at ptolemy.actor.AtomicActor.iterate(AtomicActor.java:398) > at > ptolemy.actor.sched.StaticSchedulingDirector.fire(StaticSchedulingDirector.java:170) > at ptolemy.actor.CompositeActor.fire(CompositeActor.java:400) > at ptolemy.actor.Manager.iterate(Manager.java:688) > at ptolemy.actor.Manager.execute(Manager.java:332) > at ptolemy.actor.Manager.run(Manager.java:1071) > at ptolemy.actor.Manager$3.run(Manager.java:1112) > > What I did is the following: > > 1- design a workflow > 2- run it > 3- save as file > > 4 - restart Kepler > 5- reload XML > 6- run > > What could be my mistake ? > > Best Regards > Guillaume > _______________________________________________ > Kepler-users mailing list > Kepler-users at ecoinformatics.org > http://mercury.nceas.ucsb.edu/ecoinformatics/mailman/listinfo/kepler-users
