Java Reference
In-Depth Information
Open Java EE standard
EJB is a critical part of the Java EE standard. This is an extremely important concept to
grasp if you're to adopt EJB. EJB 3 has an open, public API specification and compatibility
test kit that organizations are encouraged to use to create a container implementation. The
EJB 3 standard is developed by the Java Community Process (JCP), consisting of a nonex-
clusive group of individuals driving the Java standard. The open standard leads to broader
vendor support for EJB 3, which means you don't have to depend on a proprietary solution.
Broad vendor support
EJB is supported by a large and diverse variety of independent organizations. This includes
the technology world's largest, most respected, and most financially strong names, such as
Oracle and IBM, as well as passionate and energetic open-source groups like JBoss and
Apache. Wide vendor support translates to three important advantages for you. First, you're
not at the mercy of the ups and downs of a particular company or group of people. Second,
a lot of people have concrete long-term interests in keeping the technology as competitive
as possible. You can essentially count on being able to take advantage of the best-of-breed
technologies both in and outside the Java world in a competitive timeframe. Third, vendors
have historically competed against one another by providing value-added nonstandard fea-
tures. All of these factors help keep EJB on the track of continuous healthy evolution.
Clustering, load balancing, and failover
Features historically added by most application server vendors are robust support for clus-
tering, load balancing, and failover. EJB application servers have a proven track record of
supporting some of the largest high-performance computing (HPC)-enabled server farm
environments. More importantly, you can use such support with no changes to code, no
third-party tool integration, and relatively simple configuration (beyond the inherent work
in setting up a hardware cluster). This means that you can rely on hardware clustering to
scale up your application with EJB 3 if you need to.
Performance and scalability
Enterprise applications have a lot in common with a house. Both are meant to last, often
much longer than anyone expects. Being able to support high-performance, fault-tolerant,
scalable applications is an upfront concern for the EJB platform instead of being an after-
thought. Not only will you be writing good server-side applications faster, you can also
expect your platform to grow as needed. You can support a larger number of users without
