The IIterator interface is in the OpenEdge.DataAdmin.Lang.Collections package, along with all the other collection interfaces. This interface provides access to the methods of a general iterator object that iterates over the elements in an entity collection. You can return an instance of IIterator from any entity collection using the Iterator( ) method on the IDataAdminCollection interface (and any of its sub-interfaces). Depending on a filter argument that you can pass to an overload of the method, this IIterator object can return all or a specified subset of the elements in the collection, and in sorted order, if specified. The iterator returns collection elements as Progress.Lang.Object instances. You must then cast each instance to the appropriate interface type for entity access.