ConcurrentModificationException in DB Query handling
This happens frequently with Simupedia use.
Exception in thread "QueryListening" java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909)
at java.util.ArrayList$Itr.next(ArrayList.java:859)
at org.simantics.db.impl.query.QueryListening$Scheduler$1.run(QueryListening.java:128)
After the exception, the DB stops responding any requests. The only way to proceed is to kill the application.