Classe Robot

import java.awt.AWTException;

import java.awt.Robot;

import java.awt.event.KeyEvent;

public class RobotExp {

    public static void main(String[] args) {

        try {

            Robot robot = new Robot();

            // Cria um delay de 5 segundos de modo que você possa abrir o notepad antes da execução do código a seguir

            // Robot começa a escrever

            robot.delay(5000);

            robot.keyPress(KeyEvent.VK_O);

            robot.keyPress(KeyEvent.VK_I);

            robot.keyPress(KeyEvent.VK_SPACE);

            robot.keyPress(KeyEvent.VK_M);

            robot.keyPress(KeyEvent.VK_U);

            robot.keyPress(KeyEvent.VK_N);

            robot.keyPress(KeyEvent.VK_D);

            robot.keyPress(KeyEvent.VK_O);

        } catch (AWTException e) {

            e.printStackTrace();

        }

    }

}

    Robot robot;   

    try {   

        robot = new Robot();   

        int x;   

        Character y;   

        String msg = "testando";   

        Process p = Runtime.getRuntime().exec("c:\\windows\\system32\\notepad.exe")   ;

        robot.delay(1000);

        for(int i = 0; i < msg.length(); i++)   

        {   

            y =msg.charAt(i);   

            if(y.hashCode() > 57)

                x = y.hashCode() - 32;   

            else

                x = y.hashCode(); 

            robot.keyPress(x);   

            robot.keyRelease(x);  

            robot.delay(200);

        }   

    } catch (AWTException e) {   

        // TODO Bloco catch gerado automaticamente   

        e.printStackTrace();   

    }