Developing Message-Driven Beans 

Message-driven beans have the following features:

·        A message-driven bean can process multiple JMS messages asynchronously

·        The beans are invisible to clients

·        The beans are stateless

·        All instances of a message-driven bean are equivalent

When to Develop Message-Driven Beans

You can develop message-driven beans if:

·        You want your application to process asynchronous JMS messages

Future versions of the Enterprise JavaBeans specification are expected to cover the processing of other types of messages (not only JMS messages) by message-driven beans.

The Development Process

The process of developing a message-driven bean consists of the following steps:

...

       1.      Define the functions of the bean

       2.      Develop the clients, which will invoke the message-driven bean methods

       3.      Develop the source code of the message-driven bean. That is:

...

                            a.      The message-driven bean class

                            b.      The deployment descriptors

       4.      Create the Connection Factory

       5.      Create the Destination (Queue or Topic)

       6.      Compile and pack the bean components in a JAR file

       7.      Pack the whole application in an EAR file

       8.      Deploy the application on SAP J2EE Engine

       9.      Start the application.