Oracle Containers for Java

The Oracle Application Server 10g provides its own J2EE container, called the Oracle Containers for J2EE (OC4J). OC4J is an easy-to-use, lightweight, and highly scalable J2EE container that is written entirely in Java. OC4J is a complete Java 2 Enterprise Edition (J2EE) environment that runs on the Java Virtual Machine (JVM) of the standard Java Development Kit (JDK). OC4J runs on the standard JDK that’s a part of your operating system. Oracle bases its OC4J framework on technology licensed from Ironflare Corporation, developers of a leading J2EE container called the Orion Server. Thus, you’ll see several references in the OracleAS OC4J documentation to the Orion Server, and some of the OC4J executables contain their original Orion Server--based names.

OC4J is a set of containers that enable J2EE application deployment. For example, OC4J provides a Web Container to support JSP page translation as well as execution with a servlet engine. OC4J also provides an EJB container. As mentioned earlier, OC4J provides J2EE services such as JNDI, JDBC, JTA, JCA, and JAAS.

In this chapter, OC4J is discussed as part of the full OracleAS 10g product set, not its alternative pure Java standalone distribution. The pure Java standalone distribution is easy to download (one Zip file), install, and configure. However, the standalone distribution is really suited for development and testing only. For large-scale applications, you must use OC4J with the full OracleAS environment to take advantage of the full-fledged Oracle HTTP Server, Single Sign-On, and many other advanced features.

However, because the standalone and the OracleAS-based OC4J distributions are identical, you can use the standalone version to develop enterprise applications that you can later deploy on the Oracle Application Server 10g.

on the job:  The mod_oc4j module routes requests from the Oracle HTTP Server to OC4J.