O'Reilly - Java Message Service

}
Topic topic = (Topic)textMessage.getJMSDestination( );
System.out.println(topic.getTopicName( )+" : "+text);
} catch (JMSException jmse){jmse.printStackTrace( );}
Java Message Service
The JMSDestination header is set automatically by the JMS provider when the message is
delivered. The Destination used in the JMSDestination is typically specified when the
publisher is created, as shown here:
Queue queue = (Queue)jndi.lookup(queueName);
QueueSender queueSender = session.createSender(queue);
Message message = session.createMessage( );
queueSender.send(message);
...
Topic topic = (Topic)jndi.lookup(topicName);
TopicPublisher topicPublisher = session.createPublisher(topic);
Message message = session.createMessage( );
topicPublisher.publish(message);
An unspecified message producer - one created without a Destination - will require that a
Destination be supplied with each send( ) operation:
QueueSender queueSender = session.createSender(null);
Message message = session.createMessage( );
Queue queue = (Queue)jndi.lookup(queueName);
queueSender.send(queue, message);
...
TopicPublisher topicPublisher = session.createPublisher(null);
Message message = session.createMessage( );
Topic topic = (Topic)jndi.lookup(topicName);
topicPublisher.publish(topic, message);
In this case, the JMSDestination header becomes the Destination used in the send( )
operation.
JMSDeliveryMode Purpose: Routing
There are two types of delivery modes in JMS: persistent and nonpersistent. A persistent
message should be delivered once-and-only-once, which means that a message is not lost
if the JMS provider fails; it will be delivered after the server recovers. A nonpersistent
message is delivered at-most-once, which means that it can be lost and never delivered if
the JMS provider fails. In both persistent and nonpersistent delivery modes the message
server should not send a message to the same consumer more than once, but it is possible;
see the section on JMSRedelivered for more details.
Persistent messages are intended to survive system failures of the JMS provider (the
message server). Persistent messages are written to disk as soon as the message server
receives them from the JMS client. After the message is persisted to disk the message
server can then attempt to deliver the message to its intended consumer. As the messaging
server delivers the message to the consumers it keeps track of which consumers
successfully receive the message. If the JMS provider fails while delivering the message,
the message server will pick up where it left off following a recovery. Persistent messages
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