How to run two threads in another created class?

Jhonathan Cavalcante :

I need to run a Server and Client in a application that trade string messages with each other(a chat), the code for this is working, part of it was provided by the teacher, but i'm stuck in one thing.

I want to run a class named "App", who creates a new Server and a new Client, but when i run both of then in the class, only one works.

package app;

import udp.Client;
import udp.Server;

public class App {

public static void main(String[] args) {

    Server s = new Server();
    s.Start();



    Client c = new Client();
    c.Start();



}
}

So to run the both of then, Server and Client, i need to comment out the client one, run the Server instance, then comment out the Server one, and run the Client instance, both classes initialize a thread.

How can i run both of then without that improvisation? I wanna hit "Run", and the code pops up the Server and the Client window.

I can provide the rest of the code if it's necessary.

Michel_T. :

new Thread(() ->
{
    Server s = new Server();
    s.Start();
}).start();

new Thread(() ->
{
    Client c = new Client();
    c.Start();
}).start();