Message listeners allow you to receive messages asynchronously. Once you have implemented a listener, install it on a message consumer. When a message is delivered to the message consumer, the listener can process the message or send it to other consumers.
The message service implements two types of JMS message listeners:
Message-driven beans – see “Message-driven beans”.
Client-side – you can associate a client-side JMS message listener with a message consumer programmatically.
A message listener implements the javax.jms.MessageListener interface, which contains only the onMessage method. This example illustrates the skeleton code for a message listener:
class QueueMessageListener implements MessageListener
{
public void onMessage(javax.jms.Message msg)
{
// process message
}
}
To install a client-side message listener, first create a message consumer (see “Creating message consumers”), then install the listener, using this syntax:
myConsumer.setMessageListener(new MessageListener());
