Chapter 5 Client Design

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gui.setStatus("");

JOptionPane.showMessageDialog(gui, 

"Order Not found with Order ID " + orderId,

"Error",

JOptionPane.ERROR_MESSAGE);

} catch (Exception ex) {

// do nothing for now

}

gui.setStatus("Completed lookup for order ID " + orderId);

SwingUtilities.invokeLater(this);

done = true;

}

}

}

Code Example 5.19

J2SE Client Using 

SwingUtils.invokeLater

This example illustrates how a J2SE client can use the J2SE platform APIs to

enhance the user experience. In this example, the user has selected an option to

track an order currently being handled by the Web service. That option calls the

invokeLater

 method, which in turn invokes a class implementing the 

Runnable

interface. This class, using a callback mechanism, updates the user with messages

indicating the status of the Web service call and details pertaining to the order

being tracked. If the order is not found, the code handles displaying to the user a

suitable error message indicating the exception. 

Note:

 More information is available on the 

SwingUtilities

 API, along with

using threads and GUIs with J2SE clients. You can find this information at

http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html

.

5.4.3 Server Side Design Considerations for Clients

It should be clear by now that client developers and service endpoint providers do

not operate in a vacuum. When it is known that the target client environment is

based on JAX RPC, the service endpoint developer can provide prepackaged librar 

ies and server side documentation. These libraries should contain all files, such as

the client side representation of the service endpoint interface and its dependent

classes, that are necessary to access the service. The library can include additional

facade classes that simplify the client view of the service and potentially shield the