Question

I would like to invoke a thread within my program that constantly watches the keyboard and if a certain key is pressed then tell me (system.out).

The problem is that the KeyListener interface must have focus for it to return keystate.
http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html

Is there a different way to determine the state of the keys on the keyboard?

My aim is to see that the user pressed ctrl+n, if so, update the system clipboard text to something.

CODE:

class KeyboardWatcher extends Thread 
{
    boolean flag = false;
    public void run()
    {
        while(!flag)
        {
            if (shift & n are pressed)
            {
                StringSelection stringSelection = new StringSelection("Clip Text");
                Clipboard clpbrd = Toolkit.getDefaultToolkit().getSystemClipboard();
                clpbrd.setContents(stringSelection, null);
                flag = true;
            }
        }
        return;
    }
}

Answer 1

This is not possible without Java Native Interface. You will need a keyboard hook at the OS API level. There are many available solutions you could reuse. Look at this for one such example.