Hi All,    I am getting the following eror when i use "from collect" key word. Help me to resolve this.Thanks in advance to all.   my rule is....    Rule "test" when             $inputObj : QuotationSearchFormObject( extensions != null )    QuotationLineExt( $locFrmLabel:label == 'Location From' , value != null , $locFromValue : value ) from $inputObj.getExtensions()     i : ArrayList( size > 0  ) from collect ( QuotationLine(  extensions  != null ) from $totList); then  System.out.println("success"); end   Error marked in red colour line.     java.lang.ClassCastException: org.drools.reteoo.CollectNode$CollectMemory cannot be cast to org.drools.reteoo.FromNode$FromMemory  at org.drools.reteoo.FromNode.assertLeftTuple(FromNode.java:93)  at org.drools.reteoo.CompositeLeftTupleSinkAdapter.doPropagateAssertLeftTuple(CompositeLeftTupleSinkAdapter.java:145)  at org.drools.reteoo.CompositeLeftTupleSinkAdapter.createAndPropagateAssertLeftTuple(CompositeLeftTupleSinkAdapter.java:57)  at org.drools.reteoo.LeftInputAdapterNode.assertObject(LeftInputAdapterNode.java:142)   Thanks Dilip.