ex6_38.txt

j2ee core design patterns

Example 6.38 WebApplicationController Implementation
// Application Controller implementation responsible for handling 
// Web application requests
class WebApplicationController implements ApplicationController {

  public void init() { }

  public ResponseContext handleRequest(RequestContext requestContext) {
    ResponseContext responseContext = null;
    try {
      // Identify command name
      String commandName = requestContext.getCommandName();

      // resolve command name to Command Object
      CommandFactory commandFactory = CommandFactory.getInstance();
      Command command = commandFactory.getCommand(commandName);

      // Execute Command using CommandProcessor
      CommandProcessor commandProcessor = new CommandProcessor();
      responseContext = commandProcessor.invoke(command,
          requestContext);
    } catch (java.lang.InstantiationException e) {
      // Handle Exception
    } catch (java.lang.IllegalAccessException e) {
      // Handle Exception
    }
    return responseContext;
  }
  . . .
}