collectList on objects of type java.lang.Class get returned as null ------------------------------------------------------------------- Key: DROOLS-626 URL: https://issues.jboss.org/browse/DROOLS-626 Project: Drools Issue Type: Bug Affects Versions: 6.2.0.Beta1 Environment: Snapshot Drools 6.2.0.201410031437 runtime Reporter: David Fell Assignee: Mario Fusco If collectList in an accumulate is supplied objects of type java.lang.Class, then subsequent examination of the supplied list yields null values rather than the expect Class values. Test case below. Swapping the comments to make InitClass have a String field instead of a Class field changes the behaviour of the list from collectList to what one would expect. package com.sample declare MyClass end declare InitClass clazz: Class @key // clazz: String @key end rule "init" when then insert( new InitClass( MyClass.class ) ); // insert( new InitClass( "some string" ) ); end rule "make init classes" when accumulate( InitClass( $clazz; ), $list: collectList( $clazz ) ) then System.out.printf("%d items in list\n", $list.size()); for(Object obj : $list) System.out.printf("item is %s\n", obj); end rule "show init classes" when InitClass( $v; ) then System.out.printf("match %s\n", $v); end