}
if (!mapping.isCollectionMapping()){
throw QueryException.mapEntryExpressionForNonCollection(getBaseExpression(), getMapping());
}
InterfaceContainerPolicy cp = null;
try{
cp = (InterfaceContainerPolicy)getMapping().getContainerPolicy();
} catch (ClassCastException e){
throw QueryException.mapEntryExpressionForNonMap(getBaseExpression(), getMapping());
}