dynamic_dispatch_controller.rs

struct Message<'a> {
    transaction_id: &'a [u8],
}

struct RequestHandler<'a> {
    handler: Box<Controller>,
    request: Message<'a>,
}

impl<'a> RequestHandler<'a> {
    pub fn new(message: Message, handler: Box<Controller>) -> RequestHandler {
        RequestHandler {
            request: message,
            handler: handler,
        }
    }

    fn exec(&self) {
        self.handler.execute();
    }
}

trait Controller {
    fn execute(&self);
}

struct StartController;
impl Controller for StartController {
    fn execute(&self) {
        eprintln!("{}", "StartController");
    }
}

struct BlogController;
impl Controller for BlogController {
    fn execute(&self) {
        eprintln!("{}", "BlogController");
    }
}

fn get_controller(action_type: u8) -> Option<Box<dyn Controller>> {
    match action_type {
        0x00 => Some(Box::new(BlogController {})),
        0x01 => Some(Box::new(StartController {})),
        _ => None,
    }
}

fn main() {
    let controller = get_controller(0x00).unwrap();

    let handler = RequestHandler::new(
        Message {
            transaction_id: &[0x00],
        },
        controller,
    );

    handler.exec();
}