RequestHelper, Command? FrontController!

Senhores,

No site: http://java.sun.com/blueprints/corej2eepatterns/Patterns/FrontController.html, tem pequenos exemplos de codificação do Pattern Front Controller, porém lá utiliza-se duas classes, RequestHelp e Command, consigo deduzir seus significados e ações, mas existe implementação exemplo para elas?

Grato,
Pablo

Os dois também são patterns…
e tu pode encontrar no mesmo local :wink:

Helper
http://java.sun.com/blueprints/corej2eepatterns/Patterns/ViewHelper.html

Command

http://java.sun.com/blueprints/corej2eepatterns/Patterns/ServiceToWorker.html

fui…

Eu implementei minha própria classe RequestHelper:

[code]public class RequestHelper {
HttpServletRequest request;
public RequestHelper (HttpServletRequest request) {
this.request = request;
}

public Command getCommand() throws Exception {
	String commandName = "<nomeDoPacote>" + request.getParameter("helper");
	System.out.println("commandName = " + commandName);
	
	Class businessLogicClass = Class.forName(commandName);
	if (!Command.class.isAssignableFrom(businessLogicClass)) {
		throw new ServletException("classe nao implementa a interface: " + commandName);
	}
	return (Command) businessLogicClass.newInstance();
}

}[/code]

Command ficou assim:

public interface Command { void execute (HttpServletRequest req, HttpServletResponse res) throws Exception; }