How to run a thread separate from main thread in Java?

Question

The goal is to be able to invoke execution of a separate thread from within the main class.

Some context: I have a program that must ru

Answer 1

Create a separate thread that executes your external program:

class MyRunner implements Runnable{
  public void run(){
     Runtime.exec("your cmd")
  }
}

then start the thread in your main():

MyRunner myRunner = new MyRunner(); 
Thread myThread = new Thread(myRunner);
myThread.start();

This way your main program will continue running, while your background thread will start an external process and exit when this program exits.