This interface defines a method that may be invoked if an unsolicited
notification is received from the directory server. An unsolicited
notification handler should be defined in the
to be called whenever an unsolicited
notification is received for that connection.
An unsolicited notification is a type of extended response that is sent from
the server to the client without a corresponding request, and it may be used
to alert the client of a significant server-side event. For example,
section 4.4.1 of RFC 4511
defines a notice of disconnection unsolicited notification that can be used
by the server to inform the client that it is about to close the connection.
Implementations of this interface should be threadsafe to ensure that
multiple connections will be able to safely use the same