Implemented by objects that can have a JMXServiceURL address.
 All JMXConnectorServer objects implement this interface.
 Depending on the connector implementation, a JMXConnector
 object may implement this interface too.  JMXConnector
 objects for the RMI Connector are instances of
 RMIConnector which
 implements this interface.
 An object implementing this interface might not have an address
 at a given moment.  This is indicated by a null return value from
 JMXAddressable.getAddress().