Concrete subclasses are expected to derive from this class to provide
knowledge about a particular kind of definition format by implementing the
abstract template methods in this class.
By default, when configuring the flowLocations property, flow
definition registered by this registrar will be assigned a registry
identifier equal to the filename of the underlying definition resource, minus
the filename extension. For example, a XML-based flow definition defined in
the file "flow1.xml" will be identified as "flow1" when registered in a
For full control over the assignment of flow identifiers and flow properties,
instances using the flowDefinitions property.