Publishing a message means sending it to all clients subscribed to a topic. The
message itself nominates the topic to which it relates.
A message for publishing can be created and populated by the publisher and then
published using publishing methods on the topic or the publisher itself.
Exclusive messages
To send a message from a publisher to
all clients subscribed to a topic except one single client, it can use the
publishExclusiveMessage method. This might be appropriate if the message being published
is a result of receiving a message from a client which you do not want to send back to
that client.
Message priority
The priority at which a message is to be sent can be
altered from the normal priority. For example, an urgent message can be sent with high
priority causing it to go to the front of the client's queue.
Message acknowledgment
If acknowledgment of a message is required
then it can be set as an acknowledged message. If any clients do not respond to a
acknowledged message within a specified timeout, the publisher is notified on its
messageNotAcknowledged method.