9.1 The Platform

A platform provides application developers with a full abstraction of a generic computing environment. The Windows platform, for example, is a suite of APIs that enables developers to write desktop applications for any system running Windows, regardless of the underlying hardware they are using. The main Java platform, Java 2 Standard Edition (J2SE), does the same thing except its abstraction spans all desktop systems.

Whereas the J2SE platform creates a standard for desktop programming independent of hardware and operating system, the J2EE platform provides a standard for enterprise systems. It is a superset of J2SE. It adds the following abstractions:

• Enterprise JavaBeans (EJB)

• Java Servlets

• JavaServer Pages (JSP)

• Java Naming and Directory Interface (JNDI)

• Java Transaction Architecture (JTA)

• Java Message Service (JMS)

• Java Mail

• J2EE Connector API

• XML support

Two APIs critical to the J2EE platform, JDBC Data Access and Remote Method Invocation (RMI), predate the J2EE platform and exist in the J2SE platform.

The focus of this book is simply one aspect of J2EE programming, application persistence through relational databases. A full discussion of the J2EE platform is thus beyond the scope of this book. Nevertheless, as a database programmer, a foundation in a few of these APIs is important. I provide an overview of JNDI, JavaServer Pages, RMI, and Enterprise JavaBeans here. Later in the book, I provide a more detailed tutorial on JDBC.