Chapter 6. Oracle Application Server Containers for J2EE

The Oracle Application Server Containers for J2EE product provides the Java environment for the Oracle Application Server. OC4J is a 100% pure Java J2EE Server. As such, it can use ”and applications can be developed with ”any standard Java Development Kit (JDK). This standardization allows you the option of using the JVM that best leverages your hardware platform. OC4J has J2EE-certified Servlet and EJB containers, and a JSP translator. OC4J provides all the standard J2EE services such as session, transaction, and persistence management.

Table 6-1 lists the various J2EE APIs supported by the OC4J releases at the time of this writing.

Table 6-1. OC4J J2EE API support

	Release
API	9.0.1	9.0.2	9.0.3	9.0.4
Java Development Kit (JDK)	1.1	1.3	1.3	1.4
Enterprise JavaBeans (EJB)	1.1	1.1+	2.0	2.0
J2EE Connector Architecture		1.0	1.0	1.0
Java Authentication and Authorization Service (JAAS)		1.0	1.0	1.0
JavaMail API		1.1.2	1.1.2	1.1.2
Java API for XML Parsing (JAXP)		1.0	1.1	1.1
Java Database Connectivity (JDBC)	1.1	2.0	2.0+	2.0+
Java Message Service (JMS)	1.0.1	1.0.1	1.0.2	1.0.2b
Java Naming and Directory Interface (JNDI)		1.2	1.2	1.2
JavaServer Pages (JSP)	1.0	1.1	1.2	1.2
Java Transaction API (JTA)		1.0.1	1.0.1	1.0.1
Java Servlet	2.0	2.3	2.3	2.3

This information may be out of date by the time you read this, but the list demonstrates Oracle's commitment to support the most current versions of J2EE APIs in a timely manner. If you're interested in knowing what J2EE APIs are currently supported, go to the Oracle Technology Network web site at http://otn.oracle.com and look up the information under documentation, application server, OC4J User's Guide .

As discussed in Chapter 2, OC4J can be clustered across hosts to provide almost unlimited horizontal scaling to satisfy any level of demand. However, OC4J can also be configured with several instances on a host to ease the management of applications, or to run as a lightweight standalone server for application development purposes.

A great deal of what we describe in this chapter is standard J2EE functionality. Nevertheless, we cover this functionality to ensure that readers of all levels will be able to understand the added value the J2EE portion of Oracle Application Server provides. In addition, this chapter covers Oracle value-added services, touches on server management, discusses how deployment is supported, examines standalone configuration, and finishes up with the impact that clustering the OC4J has on maintaining state in J2EE applications.