There are two possibilities to implement cascading over Java DMK legacy connectors.
Use the legacy cascading service that was provided in earlier versions of the Java DMK. This legacy cascading service is still provided for reasons of backwards compatibility, but it is now deprecated. This alternative is therefore not recommended.
Create a JMXServiceURL from which a JMXConnector wrapping a legacy Java DMK ConnectorClient can be obtained from the JMXConnectorFactory. You can then use this JMXServiceURL with the new CascadingServiceMBean API. See the Java Dynamic Management Kit 5.1 Tutorial for more information about wrapping legacy connectors.