Working Process of JBoss AS:

The JBoss creates an MBean server instance in one of the first steps when it starts up. Then, it plugs the manageable MBean components by registering with the MBean server that is a registry for Mbeans.

JBoss implements the classloading M-Let service dynamically, which treats as an agent service. This service allows registering of the MBeans (specified in a text based configuration files) to the MBean server.

The functionality is provided by MBeans actually instead of the JMX MBean server. The MBean server is only the sense of a microkernel aggregator component that interconnects the Mbeans.

In the architecture of Jboss we can also see the EJB Container as the core implementation of JBoss server that supports its Plugins, InstancePool, EntityPersistenceManager, StatefulSessionPersistenceManager, to provide EJB services to a particular EJB.

Getting familiar with JBoss AS 4.2.1.GA

JBoss AS 4.2.1.GA is the first bug fixing release version of the JBoss Application Server v4.2 series. Its aim is to fix the most important bugs against JBossAS v4.2.0.GA that are reported by the community. There are a few minor components are upgraded (Hibernate, JacORB, JBoss TS, JBoss Remoting and Sun JSF) in this released version.

In this tutorial of JBoss AS, we have used JBoss AS 4.2.1.GA version in which you will learn, how to deploy and run an EJB-based application.

I. Downloading and Installing JBoss AS 4.2.1.GA

The JBoss application server 4.2.1.GA is available as a free download from the JBoss website. You can download this version from http://labs.jboss.com/jbossas/downloads/ URL by clicking the Download button or click here to extract files to save in your disk. JBoss 4.2.1.GA Platform is easy to install. It only requires at least a Java 1.4 or Java 1.5 JVM. Apart from this, also make sure for the JAVA_HOME environment variable that is to be set to point the JDK installation.

Once you have installed JBoss 4.2.1.GA, the next step is to learn that how to start the JBoss server.

II. Starting the Server

After installing JBoss AS, you will find a bin directory inside the main JBoss directory, which contains various scripts. Click on the run.bat file to start the server on Windows, and then see the log messages from all the JBoss components as they are deployed and started
up. The last message (obviously with different values for the time and start-up speed) should look like the following.

This message verifies that the JBoss as a web server is running on port 8080 (Make sure you don’t have anything else already on your machine using that port).

III. Stopping the Server

To stop the server, you can either press Ctrl+C on the console or you can run the shutdown script shutdown.bat from the bin directory. Alternatively, you can use the management console. Look for type=Server under the jboss.system domain and invoke the shutdown
operation.