Access the object Inside Anonymous Handler function

Question

I have a very basic question. I have just started with vertx Framework. There is one thing I am not able to understand like

vertx.createNetServer().connectHandler(new Handler<NetSocket>() {
@Override
public void handle(final NetSocket socket) {

    socket.dataHandler(new Handler<Buffer>() {
        public void handle(Buffer buffer) {
            /* I can access the socket object inside this handler */
            socket.write("Hello");
        }
    });
}
}).listen(1234);

but if I write the handler function separately like this

Handler<Message> socketHandler = new Handler<Buffer>() {
        public void handle(Buffer buffer) {
            /* How can i access the socket object now */
            socket.write("Hello"); //this will give error as it does not recognize the socket object
        }
    };


vertx.createNetServer().connectHandler(new Handler<NetSocket>() {
@Override
public void handle(final NetSocket socket) {
    socket.dataHandler(socketHandler);//now I write handler separately
}
}).listen(1234);

Handler can be anywhere in the same java class or other java class. Please help me me how I can write handler separately and still access the socket object.

Answer 1

In your second example, you're not passing socket to socketHandler, so you cannot expect socketHandler to know about it.

You could solve this by creating a method like createSocketHandler(final Socket socket) that returns a Handler<Message> and that replaces your socketHandler variable.

To learn more, and to find out why you need socket to be final, look up "anonymous inner classes"