Summary

In this chapter, we learned about Java Virtual Machines (JVMs), the web container, virtual hosts,and about deploying applications. We have covered the three different file types used in J2EE applications. A JAR file contains Java utility classes, EJBs, and sometimes shared libraries alongside other manifest information. WAR files are the containers for web application artefacts and EAR files can contain a mixture of WARs and JARs. We deployed two types of applications, one being a simple web application and the other being a data access application which was connected to a database. In this chapter, we focused on Oracle, however, we know that we could use any other database vendor and WebSphere can be easily configured to talk to other RDBMS types. We focused on manual deployments in the installation of applications and later, in Chapter 4, we will cover how to automate deployments using administrative scripting.