extension classes allow you to extend
functionality by declaring interface types that may attach to
instances. An attached extension creates an instance of the interface that
wraps method invocations in an extension context. The context has a
configuration and remembers the currently executing extension method.
An ExtensionFactory instance provides the actual extension instances and
implements the behavior of the extension.
Some built in features such as SQL Objects are themselves implemented as extensions.
ClassDescriptionFactory interface used to produce Jdbi extension objects.Configuration class for defining
ExtensionFactoryinstances.A handle supplier for extension implementors.Thrown when an extension of an unknown type is created.