"Unknown boolean operator" RuntimeException ------------------------------------------- Key: DROOLS-319 URL: https://issues.jboss.org/browse/DROOLS-319 Project: Drools Issue Type: Bug Security Level: Public(Everyone can see) Affects Versions: 5.5.0.Final Environment: Windows 8, java version "1.7.0_40" Reporter: David Tombs Assignee: Mark Proctor Steps to reproduce: # Create a decision table with something like {{fooString != ""}} in the constraint and {{true}} in the rule cell. # Execute the rule against a few objects. Actual Result: An internal Drools thread will crash with {{java.lang.RuntimeException: Unknown boolean operator}} when trying to compile {{fooString != "" == true}}. Expected Result: Even if an Exception is thrown, the currently-thrown exception is too low level and took me lots of investigation and debugging inside the drools code to figure out what I did wrong.