Testing J2EE Application Clients

J2EE application clients are like regular Java applications. They contain a main() method that is executed, and they continue executing until the client virtual machine terminates. They can be run as typical "fat client" applications, to display a GUI that connects to a set of EJBs for persistence and business logic, or as server applications that provide services over the network. However, a J2EE application client has several advantages over regular Java applications, because it runs within a lightweight server container. This container can provide the application client with services that used to be available only to other J2EE components.

Prerequisite: Create an EAR that contains a complete application client project.

Benefits of using J2EE application clients instead of regular Java applications include:

• Ability to run inside a server container, providing richer APIs.

• Use of J2EE security, including authentication and server-specific functions, that might include features such as single-sign-on.

• Guaranteed Java 2 platform APIs available, as well as container extensions.

• Simple JNDI lookup, because initial context properties are picked up from the container.

• Packaged like other J2EE components, providing portability, easy deployment, and clean packaging. This also supports the J2EE notion of a deployer being able to modify the deployment information in order to move to a different server without changing code.

• Use of the java:comp namespace to indirectly reference EJBs.

To build a full command line to launch an application client, do the following:

1. Switch to the Debug perspective (Window > Open Perspective > Other > Debug).

2. In the main toolbar, click the Run icon

   and select Run, alternatively click the Debug icon

   and select Debug.

3. In the Launch Configurations pane, select the type of configuration that you want to create, either WebSphere v4, v5, or v51 Application Client and click New.
   Important: The WebSphere v4 Application Client launcher supports J2EE level 1.2. The WebSphere v5 and v51 Application Client launcher supports both J2EE levels 1.2 and 1.3.

4. In the Name field, enter the name of your configuration.

5. In the Application tab, select an Enterprise Application from the Enterprise Application list.

   If selected, the Profile process (non-debug mode only) check box allows you to use the profiling tools provided in the workbench to analyze the performance of your client application. You cannot use profiling when the server is started in debug mode. For more information on profiling an application, refer to the Application profiling documentation.

   If you want to make changes to your code while you are debugging, select the Enable hot method replace in debug mode check box.

6. In the Arguments tab, you can add Program arguments and VM arguments as well as specifying your working directory. All WebSphere Application Server client launcher arguments begin with -CC. The default Program argument is -CCverbose=true, which will provide useful debugging information and at run-time. Any arguments that do not start with -cc will be passed to your application at run-time. For more information on the various Program arguments and VM arguments, refer to the WebSphere Application Server documentation for the Launch Client tool

7. When you have completed configuring your launch configurations, click Apply to set your configuration, then click Run to launch the application client.

Note: You may get an org.omg.CORBA.COMM_FAILURE when trying to access a test environment from a J2EE client running on a remote machine. You have to configure the ORB bootstrap host name defined in the remote server configuration to fix the problem. To edit the ORB bootstrap host name, go to the Ports page of the server editor. In the ORB bootstrap port section, type the remote host name in the Host name field. Save the editor and restart the test environment.

 

Parent topic

Testing applications on a server