Prepare the EJB Application for Assembly

To prepare the application for deployment, you do the following:

1. Modify the application.xml file with the modules of the enterprise Java application.

2. Archive all elements of the application into an EAR file.

These steps are described in the following sections:

• Modify the Application.XML File

• Create the EAR File

Modify the Application.XML File

The application.xml file acts as the manifest file for the application and contains a list of the modules that are included within your enterprise application. You use each <module> element defined in the application.xml file to designate what comprises your enterprise application. Each module describes one of three things: EJB JAR, Web WAR, or any client files. Respectively, designate the <ejb>, <web>, and <java> elements in separate <module> elements.

• The <ejb> element specifies the EJB JAR filename.

• The <web> element specifies the Web WAR filename in the <web-uri> element, and its context in the <context> element.

• The <java> element specifies the client JAR filename, if any.

As Figure 10-2 shows, the application.xml file is located under a META-INF directory under the parent directory for the application. The JAR, WAR, and client JAR files should be contained within this directory. Because of this proximity, the application.xml file refers to the JAR and WAR files only by name and relative path—not by full directory path. If these files were located in subdirectories under the parent directory, then these subdirectories must be specified in addition to the filename.

Figure 10-2 Archive Directory Format

Description of the illustration primer3.gif

For example, the following example modifies the <ejb>, <web>, and <java> module elements within application.xml for the Hello EJB application that also contains a servlet that interacts with the EJB.

<?xml version="1.0"?>
<!DOCTYPE application PUBLIC "-//Sun Microsystems, Inc.//DTD J2EE Application 1.2//EN" "http://java.sun.com/j2ee/dtds/application_1_2.dtd">
<application>
  <display-name>helloworld j2ee application</display-name>
  <description>
     A sample J2EE application that uses a Helloworld Session Bean
     on the server and calls from java/servlet/JSP clients.
  </description>
  <module>
    <ejb>helloworld-ejb.jar</ejb>
  </module>
  <module>
    <web>
      <web-uri>helloworld-web.war</web-uri>
      <context-root>/helloworld</context-root>
    </web>
  </module>
  <module>
    <java>helloworld-client.jar</java>
  </module>
</application>

Create the EAR File

Create the EAR file that contains the JAR, WAR, and XML files for the application. Note that the application.xml file serves as the EAR manifest file.

To create the helloworld.ear file, execute the following in the hello directory contained in Figure 10-2:

% jar cvf helloworld.ear . 

This step archives the application.xml, the helloworld-ejb.jar, the helloworld-web.war, and the helloworld-client.jar files into the helloworld.ear file.