...
Geronimo server comes with a JMS server and application components that can access JMS resources like connection factories, topics and queues from it. This JMS server (is) also known as message broker. The default message broker supports(supported) by Geronimo is ActiveMQ, usually does not need to be changed since it is a mature and feature-rich JMS product. This implementations uses (use) inbuilt Derby database for the message persistent features.
ActiveMQ supports a large variety of transports (such as TCP, SSL, UDP, multicast, intra-JVM, and NIO) and client interactions (such as push, pull, and publish/subscribe).In (the) Geronimo context ActiveMQ supports MDBs, which are EJBs that consume JMS messages. It allows JMS applications to take J2EE specific features from Geronimo and application components such as JSPs, Servlets or EJBs utilizing JMS. Geronimo has been implemented this JMS API in an abstract layer to support any JMS provider. It has achieved this feature by supporting J2EE Connector (JCA) specification. The JCA 1.5 specification details the contracts required between the application server (Geronimo) and the driver supplied by ActiveMQ (resource adapter). Applications deployed in the Geronimo access ActiveMQ message broker only through this resource adapter(RA).
...
Order processing application has two defined message queues (so) as to recieve orders and consignments. Order requests can be generated and send by the Order Sender web application. When order requests are recieved to the order queue, a MDB will be triggered. It will carry out the next level of order request processing by saving those requests in to a server repository. Those saved order requests will be processed by a company employee.
Compnay's (The company's) sales agents are using the Consignment Sender application to send consignment (collection of orders) requests from their locations. First they will prepare consignment as an XML file, then it will be passed as an application parameter. Consignment Sender application will read the content of an XML file (with a consignmet(consignment) request) and send it to the consignment queue. General (M)manager in the company uses Consignment Reciever application to find out the consignment requests. When a consignment request recieved to the Consignment queue, Consignment Reciever listener application will download those requests to the responsible manager's computer. Then he will (He will then) authorize it and handed(hand) it over to a sales emplyee(employee) for further processing.
(The) Following figure gives the overall architecture of the order processing application.
...
- org.apache.geronimo.samples.order.client
- ConsignmentReciever - Listening on recieving of consignment requests to a defined queue.
- ConsignmentSender - Send consignment requests to their queue.
- org.apache.geronimo.samples.order.ejb
- OrderRecvMDB - A MDB that listens on recieving of order requests to a defined queue.
- org.apache.geronimo.samples.order.util
- PropertyLoader - Loads configuration properties to application.
- org.apache.geronimo.samples.order.web
- OrderSenderServlet - Creates order requests based on the user input and send(s) them to respective queue.
Finally, (the) core of the order placement application will be deployed as an EAR to the application server. Overview of the contents of EAR is given in the following.
...