Re: [rules-users] Strange rule compilation issue.

Ok, this one was hidden for a long time. Interesting no one stumbled on it before you. https://jira.jboss.org/jira/browse/JBRULES-2424 The problem is triggered in case your fact class/interface has a method that matches the following 3 conditions: * it is public * its name starts with "set" * it has no parameters Your fact interface had a method: public XXX setup(); That would make the ClassFieldInspector class to raise an exception, making it impossible to create any field accessors for it.

Anyway, it is fixed now on trunk (to be released in M2) and branch 5.0.x. Meanwhile, the possible workaround is to break one of the three conditions above: either make the method non-public, or rename it to not start with "set" or add at least one (dummy) parameter to it. Thanks for reporting.