O'Reilly - Java Message Service

Java Message Service
QWholesaler and QRetailer applications in separate command windows using the
following command-line options:
java chap6.B2B.QWholesaler localhost username password
java chap6.B2B.QRetailer localhost username password
In the QWholesaler application, enter the following two lines at the prompt (Item
description, Old Price, New Price):
Surfboards, 999.99, 499.99
Wetsuits, 299.99, 149.99
The QRetailer application does not respond with a "Buy Order" until you hit the Enter key
on the second line-item, because QRetailer knows that it can't buy 1000 surfboards
without also buying 1000 wetsuits to go with them. Here is the code for the autoBuy( )
method, which contains this logic:
private void autoBuy (javax.jms.Message message){
int count = 1000;
try {
StreamMessage strmMsg = (StreamMessage)message;
String dealDesc = strmMsg.readString( );
String itemDesc = strmMsg.readString( );
float oldPrice = strmMsg.readFloat( );
float newPrice = strmMsg.readFloat( );
System.out.println( "Received Hot Buy: "+dealDesc );
// "saveDesc" is our "saved" data
if ( saveDesc == null )
{
if (message.getJMSRedelivered( ))
processCompensatingTransaction( );
processInterimMessages( itemDesc );
return;
}
// If price reduction is greater than 10 percent, buy
if ((newPrice == 0 || oldPrice / newPrice > 1.1)){
TextMessage textMsg = tsession.createTextMessage( );
textMsg.setText(count + " " + saveDesc + ", "
+ count + " " + itemDesc );
textMsg.setJMSCorrelationID("DurableRetailer");
Queue buyQueue = (Queue)message.getJMSReplyTo( );
System.out.println ("\nBuying " + count + " "
+ saveDesc + " " + count + " " + itemDesc);
qsender = qsession.createSender(buyQueue);
qsender.send( textMsg,
javax.jms.DeliveryMode.PERSISTENT,
javax.jms.Message.DEFAULT_PRIORITY,
1800000);
// Acknowledge the original message
try {
System.out.println("\nAcknowledging messages");
message.acknowledge( );
System.out.println("\nMessage acknowledged");
saveDesc = null;
} catch (javax.jms.JMSException jmse){
System.out.println("\nAcknowledgment failed." +
"\nProcessing compensating transaction for "+
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