Hi Loïc, That MvelConstraint class is part of the new constraint evaluation mechanism I started developing with Drools 5.4 and further improved in the subsequent releases.
However I've never had a similar problem. I'll try to reproduce this issue based on what you wrote, but it could be very helpful if you could send a reproducer (possibly opening a ticket on jira and attaching your reproducer there). Thanks a lot for your help, Mario -- View this message in context: http://drools.46999.n3.nabble.com/rules-users-InstantiationError-during-condition-evaluation-in-Drools-6-0-0-Final-tp4027161p4027163.html Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users