Create the Deployment Descriptor

After implementing and compiling your classes, you must create the standard J2EE EJB deployment descriptor for all beans in the module. The XML deployment descriptor (defined in the ejb-jar.xml file) describes the EJB module of the application. It describes the types of beans, their names, and attributes. The structure for this file is mandated in the DTD file, which is provided at " http://java.sun.com/dtd/ejb-jar_2_0.dtd".

Any EJB container services that you want to configure is also designated in the deployment descriptor. For information about data sources and JTA, see the Oracle Application Server Containers for J2EE Services Guide. For information about security, see the Oracle Application Server Containers for J2EE Security Guide.

After creation, place the deployment descriptors for the EJB application in the META-INF directory that is located in the same directory as the EJB classes. See Figure 10-2 for more information.

The following example shows the sections that are necessary for the Hello example, which implements both a remote and a local interface.

Example 10-1 XML Deployment Descriptor for Hello Bean

The following is the deployment descriptor for a version of the Hello example that uses a stateless session bean. This example defines both the local and remote interfaces. You do not have to define both interface types; you may define only one of them.

<?xml version="1.0"?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 1.1//EN" "http://java.sun.com/j2ee/dtds/ejb-jar_1_1.dtd">

<ejb-jar>
   <display-name>hello</display-name>
   <description>
      An EJB app containing only one Stateless Session Bean
   </description>
   <enterprise-beans>
      <session>
         <description>no description</description>
         <display-name>HelloBean</display-name>
         <ejb-name>HelloBean</ejb-name>
         <home>hello.HelloHome</home>
         <remote>hello.Hello</remote>
         <local-home>hello.HelloLocalHome</local-home>
         <local>hello.HelloLocal</local>
         <ejb-class>hello.HelloBean</ejb-class>
         <session-type>Stateless</session-type>
         <transaction-type>Container</transaction-type>
      </session>
   </enterprise-beans>

   <assembly-descriptor>
      <container-transaction>
         <method>
            <ejb-name>HelloBean</ejb-name>
            <method-name>*</method-name>
         </method>
         <trans-attribute>Supports</trans-attribute>
      </container-transaction>
      <security-role>
         <role-name>users</role-name>
      </security-role>
   </assembly-descriptor>
</ejb-jar>

Note: You can download this example on OTN from the OC4J sample code page at http://www.oracle.com/technology/tech/java/oc4j/demos/ on the OTN Web site.