fix for issue #3047 (only comparable objects are supported if there is no comparator)
unit test update for issue #3047
fix for issue #3047 (throws exception in case of non-comparable)
unit test for issue #3047 (throws exception in case of non-comparable)
Merge pull request #3427 from serkan-ozal/fix/3.x/issue-3047

Fix/3.x/issue 3047