Java Reference
In-Depth Information
15
Introduction to Enterprise
JavaBeans
In This Chapter
Distributed Computing
The Different Kinds of EJBs
Container Services
The Interfaces and the Implementation Class
Accessing the Bean from the Client
Exercises
Reviewing the Exercises
Enterprise JavaBeans (EJBs) technology is one aspect of the JEE specification that
also includes specifications for servlets, messaging, Java Server Pages, and Java Mes-
saging and other components.
EJBs appear to be more difficult than they really should be. The apparent com-
plexity of the infrastructure of EJBs carries with it a big tradeoff. The JEE architec-
ture handles much of the scaling and integrity issues required for robust enterprise
code. This includes database connection pooling and transaction services, so the
bottom line is that the complexity is worth the tradeoff for these types of enterprise
applications. Simpler applications may be well served by the use of simpler archi-
tectures, such as the use of only Web server servlets for your application.
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