JBoss.org Community Documentation
JBoss Application Server 5 is built on top of the new JBoss Microcontainer. The JBoss Microcontainer is a lightweight container that supports direct deployment, configuration and lifecycle of plain old Java objects (POJOs). The JBoss Microcontainer project is standalone and replaces the JBoss JMX Microkernel used in the 3.x and 4.x JBoss Application Servers. Project goals include:
Make the JBoss Microcontainer available as a standalone project.
Embrace JBoss' POJO middleware strategy.
Enable JBoss services to be easily deployed in the other containers.
Allow the features to be used in more restrictive environments (e.g. Applets, J2ME, etc.).
Provide POJO configuration management, support for dependencies, and support for clustering.
The JBoss Microcontainer integrates nicely with the JBoss Aspect Oriented Programming framework (JBoss AOP). JBoss AOP is discussed in Chapter 7, JBOSS AOP Support for JMX in JBoss AS 5 remains strong and MBean services written against the old Microkernel are expected to work.
JBoss AS5 is designed around the advanced concept of a Virtual Deployment Framework (VDF). The JBoss5 Virtual Deployment Framework (VDF) takes the aspect oriented design of many of the earlier JBoss containers and applies it to the deployment layer. It is also based on the POJO microntainer rather than JMX as in previous releases. More information about the Virtual Deployment Framework (VDF) can be found in Chapter 6, JBoss5 Virtual Deployment Framework .
A sample Java EE 5 application that can be run on top of JBoss 5.0.0.Beta4 and above which demonstrates many interesting technologies is the Seam Booking Application available on http://seam.demo.jboss.com/home.seam. This application makes use of the following technologies running on JBoss AS5:
EJB3
Stateful Session Beans
Stateless Session Beans
JPA (w/ Hibernate validation)
JSF
Facelets
Ajax4JSF
Seam
Many key features of JBoss AS5 are provided by integrating other standalone JBoss projects which include: -
JBoss EJB3 included with JBoss 5 provides the implementation of the latest revision of the Enterprise Java Beans (EJB) specification. EJB 3.0 is a deep overhaul and simplification of the EJB specification. EJB 3.0's goals are to simplify development, facilitate a test driven approach, and focus more on writing plain old java objects (POJOs) rather than coding against complex EJB APIs.
JBoss Messaging is a high performance JMS provider in the JBoss Enterprise Middleware Stack (JEMS), included with JBoss 5 as the default messaging provider. It is also the backbone of the JBoss ESB infrastructure. JBoss Messaging is a complete rewrite of JBossMQ, which is the default JMS provider for the JBoss AS 4.x series.
JBossCache 2.0 that comes in two flavors. A traditional tree-structured node-based cache and a PojoCache, an in-memory, transactional, and replicated cache system that allows users to operate on simple POJOs transparently without active user management of either replication or persistency aspects.
JBossWS 2 is the web services stack for JBoss 5 providing Java EE compatible web services, JAXWS-2.0.
JBoss Transactions is the default transaction manager for JBoss 5. JBoss Transactions is founded on industry proven technology and 18 year history as a leader in distributed transactions, and is one of the most interoperable implementations available.
JBoss Web is the Web container in JBoss 5, an implementation based on Apache Tomcat that includes the Apache Portable Runtime (APR) and Tomcat native technologies to achieve scalability and performance characteristics that match and exceed the Apache Http server.
JBoss AS5 includes numerous features and bug fixes, many of them carried over upstream from the JBoss AS4.x codebase. See the Detailed Release Notes section for the full details.