Collections are type-unsafe by default and may lead to runtime errors --------------------------------------------------------------------- Key: DROOLS-524 URL: https://issues.jboss.org/browse/DROOLS-524 Project: Drools Issue Type: Bug Affects Versions: 5.5.0.Final, 5.6.0.Final, 6.0.0.Final, 6.0.1.Final, 6.1.0.CR1, 6.1.0.Final Reporter: Davide Sottara Assignee: Mario Fusco Priority: Minor Collections are type-unsafe, so it is possible to write constraints on non-existing fields. The compiler will not report any error, but an exception will be thrown at runtime. The configuration was needed to support map and list accessors: {code} Map( this[ "key" ].someFieldOfTheValue > 0 ) {code} but an explicit cast would be preferable {code} Map( this[ "key" ]#ClassOfTheValue.someFieldOfTheValue > 0 ) {code} This bug can't be fixed in 6.x due to backward compatibility. It will be fixed in future major versions.