An actor filter is implemented in Bonita BPM in two parts, the definition and the implementation. This enables you to change the implementation without changing the definition. Several implementations can be created for a single definition. See here for a list of actor filters provided with the product.
An actor filter is a type of connector and is created in the same way, using the same schema files as for a connector. You can define a new actor filter definition or implementation in Bonita BPM Studio, using the wizards started from the Development menu, Actor filters sub menu. You can also create a new actor filter definition or implementation externally, and import it into Bonita BPM Studio.