An HTML client is generally used for a home banking application built to
use the Branch Transformation Toolkit. An HTML client can also be used in
any other kind of application, such as a bank teller application or a CRMS.
The client machine requires only a Web browser to run the application.
When the user visits the start page of the application and logs in, the
browser displays a menu or HTML desktop with a list of available processes.
In this example, the toolkit Struts Extensions in the presentation server
controls the navigation. The application presentation layer and application
logic layer run on WebSphere(R) Application Server so that the example
can show how the application logic layer works when the work area and Process
Choreographer are not available and uses Single Action EJBs to perform the
logic.
- The user requests a customer search and provides the required input data:
- The user clicks a customer search link in the HTML desktop. This user
action sends a request to toolkit Struts Extensions.
- The toolkit Struts Extensions component in the application presentation
layer starts the corresponding action (Struts action A) specified in the Struts
configuration file. That action then returns the JSP page name. The presentation
layer processes the JSP into an HTML page.
- In the client side, the browser displays the HTML page.
- The user enters the input data and clicks a Submit button. This sends
the form data as an HTTP post request to the Action servlet of the Struts
Extensions which in turn starts a Struts action (Struts action B) specified
in the Struts configuration file. The request data contains a process ID as
hidden fields along with the other input data.
- Struts Action B requests an invoker from the Bean Invoker Factory.
- The invoker formats the data into a process context.
- The invoker calls a method in a Single Action EJB to perform a customer
search process in the application logic layer. Struts action B uses a formatter
to add data from the context as a parameter of the method call. The method
call also includes the session ID.
- The application logic layer executes the business process:
- The Single Action EJB performs the logic contained in the invoked method.
- The Single Action EJB returns the response to the presentation server.
- The client view displays a list of customers matching the search criteria:
- The invoker unformats the response into the process context.
- Struts action B points to a JSP that generates an HTML page with the response
to the customer search request. The page contains a list of customers who
match the search criteria.
- The client displays the HTML page.