As per this previous link (How to send keyboard outputs) Java can simulate a key being pressed using the Robot class. However, how could a combination of key presses be simu
This is an example
Robot r = new Robot();
Thread.sleep(1000);
r.keyPress(KeyEvent.VK_ALT);
r.keyPress(KeyEvent.VK_NUMPAD1);
r.keyPress(KeyEvent.VK_NUMPAD2);
r.keyPress(KeyEvent.VK_NUMPAD3);
r.keyRelease(KeyEvent.VK_ALT);
Don't forget to release some special keys, it will make some crazy things on your machine