PrologException with SWI-v.8.x, jpl7, Repast simphony

General
1

I am seeing the following exception when running the simulation, with Java based Repast Simphony:

FATAL [Thread-10] 20:44:57,976 repast.simphony.ui.GUIScheduleRunner - RunTimeException when running the schedule
Current tick (2.0)
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
	at repast.simphony.engine.schedule.DynamicTargetAction.execute(DynamicTargetAction.java:72)
	at repast.simphony.engine.controller.ScheduledMethodControllerAction$ScheduleMethodAllAction.execute(ScheduledMethodControllerAction.java:333)
	at repast.simphony.engine.schedule.DefaultAction.execute(DefaultAction.java:38)
	at repast.simphony.engine.schedule.ScheduleGroup.executeList(ScheduleGroup.java:205)
	at repast.simphony.engine.schedule.ScheduleGroup.execute(ScheduleGroup.java:231)
	at repast.simphony.engine.schedule.Schedule.execute(Schedule.java:352)
	at repast.simphony.ui.GUIScheduleRunner$ScheduleLoopRunnable.run(GUIScheduleRunner.java:52)
	at java.lang.Thread.run(Thread.java:821)
Caused by: java.lang.reflect.InvocationTargetException
	at caspPlainPlateauTeam.agents.CitizenAgent$$FastClassByCGLIB$$eeacca07.invoke(<generated>)
	at net.sf.cglib.reflect.FastMethod.invoke(FastMethod.java:53)
	at repast.simphony.engine.schedule.DynamicTargetAction.execute(DynamicTargetAction.java:69)
	... 7 more
Caused by: org.jpl7.PrologException: PrologException: error(type_error(free_of_attvar, ':'(user, stratum(_41, exp(_42, _43, _44, _45)))), context(':'(system, '/'('$tbl_variant_table', 6)), _46))
	at org.jpl7.Query.fetchNextSolution(Query.java:438)
	at org.jpl7.Query.hasMoreSolutions(Query.java:342)
	at org.jpl7.Query.oneSolution(Query.java:872)
	at caspPlainPlateauTeam.agents.CitizenAgent.choose_and_perform_action(CitizenAgent.java:283)
	at caspPlainPlateauTeam.agents.CitizenAgent.choose_strategy(CitizenAgent.java:209)
	... 10 more

I don’t recognise that type of Prolog error, but the code in question seems to work fine with SWI-v-7.x. I’m afraid that the Prolog code can’t be shared (I am a PhD student and the work is considered sensitive), but perhaps I can try to create a minimum working example for you, if that would be helpful.

Thanks,
Abira

2

I’d first look at this Prolog exception. Could be poor handling of the exception. Whether that is new or not, I can’t say. A small reproducible example can of course help.