Specifying a Message Listener at the Message Consumer

Figure 16-33 Use Case Diagram: Specify a Message Listener at the Message Consumer

Text description of the illustration adq16jsi28.gif

To refer to the table of all basic operations having to do with the Operational Interface see: "Use Case Model: Operational Interface -- Basic Operations"

Purpose

Specify a Message Listener at the Message Consumer

Usage Notes

Not applicable.

Syntax

See Chapter 3, "AQ Programmatic Environments" for a list of available functions in each programmatic environment. Use the following syntax references for each programmatic environment:

• See Java (JDBC): Oracle9i Supplied Java Packages Reference, oracle.jms, AQjmsConsumer.setMessageListener

Examples

See Chapter 3, "AQ Programmatic Environments" for a list of available functions in each programmatic environment.

TopicConnectionFactory    tc_fact   = null;
TopicConnection           t_conn    = null;
TopicSession              t_sess    = null;
TopicSession              jms_sess;
Topic                     shipped_orders;
int                       myport = 5521;
MessageListener           mLis = null;
/* create connection and session */
tc_fact = AQjmsFactory.getTopicConnectionFactory("MYHOSTNAME",
                                                  "MYSID", myport, "oci8");
t_conn = tc_fact.createTopicConnection("jmstopic", "jmstopic");
jms_sess = t_conn.createTopicSession(true, Session.CLIENT_ACKNOWLEDGE);

shipped_orders = ((AQjmsSession )jms_sess).getTopic("WS",
"Shipped_Orders_Topic");
/* create a subscriber, specifying the correct CustomDatumFactory  and
selector */
subscriber1 = jms_sess.createDurableSubscriber(shipped_orders,
'WesternShipping',
        " priority > 1 and tab.user_data.region like 'WESTERN %'",
         false,AQjmsAgent.getFactory());

mLis = new myListener(jms_sess, "foo");
/* get message for the subscriber, returning immediately if there was no
message */
subscriber.setMessageListener(mLis);

The definition of the myListener class
import oracle.AQ.*;
import oracle.jms.*;
import javax.jms.*;
import java.lang.*;
import java.util.*;
public class myListener implements MessageListener
{
   TopicSession   mySess;
   String         myName;

   /* constructor */
   myListener(TopicSession t_sess, String t_name)
   {
      mySess = t_sess;
      myName = t_name;
   }

   public onMessage(Message m)
   {
      System.out.println("Retrieved message with correlation: " ||
m.getJMSCorrelationID());

      try{
        /* commit the dequeue */
        mySession.commit();
      } catch (java.sql.SQLException e)
      {System.out.println("SQL Exception on commit"); }

   }

}