The installation instructions for the J2EE SDK and explain how to set the required environment variables Verify that the environment variables have been set to the values noted in Table 2 1 Table 2 1 Required Environment Variables

To launch the J2EE server, open a terminal window and type this command:

To stop the server, type the following command:

The utility has two modes: command line and GUI The instructions in this chapter refer to the GUI version To start the GUI, open a terminal window and type this command:

The sample application contains three J2EE components: an enterprise bean, a J2EE application client, and a Web component Before building these components, you will create a new J2EE application called and will store it in an EAR file named , select File New Application 1 In 2 Click Browse 3 In the file chooser, navigate to 4 In the File Name field, enter 5 Click New Application 6 Click OK

An enterprise bean is a server-side component that contains the business logic of an application At runtime, the application clients execute the business logic by invoking the enterprise bean s methods The enterprise bean in our example is a stateless session bean called The source code for is in the directory

The enterprise bean in this example requires the following code: Remote interface Home interface Enterprise bean class

A remote interface defines the business methods that a client may call The business methods are implemented in the enterprise bean code The source code for the remote interface follows

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A home interface defines the methods that allow a client to create, find, or remove an enterprise bean The interface contains a single create method, which returns an object of the remote interface type Here is the interface: source code for the

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The enterprise bean class for this example is called implements the two business methods, and remote interface defines The source code for the class follows

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