// imports not included

public class ReflectionExample {
  public static void main(String[] args) {
    JarClassLoader loader = new JarClassLoader(myJarPath);
    Class<?> clientMainClass = loader.loadClass("MAIN-CLIENT-CLASS-GOES-HERE");
    Method clientMainMethod = clientMainClass.getDeclaredMethod("main", new Class<?>[]{String[].class}); // get client main(String[] args) method

    JFrame controlPanel = new JFrame("Control Panel");
    JButton b=new JButton("Click Me");
    b.setBounds(0, 0, 100, 100);
    b.addActionListener(new ActionListener() { // add click handler to button
      public void actionPerformed(ActionEvent e) {
        for (Field f : clientMainClass.getDeclaredFields()) { // loop over all fields
          if (f.getType().equals(JFrame.class)) { // check if field type is JFrame
            System.out.println("Found field: " + f.getName());
            JFrame gameFrame = f.get(null); // get static field
            Point screenLoc = gameFrame.getLocationOnScreen();
            Robot robot = new Robot();
            Color targetColor = new Color(255, 0, 0); // the color you are searching for
            for (int y = 0; y < gameFrame.getHeight(); y++) {
              for (int x = 0; x < gameFrame.getWidth(); x++) {
                int screenX = (int)(screenLoc.getX() + x);
                int screenY = (int)(screenLoc.getY() + y)
                Color c = robot.getPixelColor(screenX, screenY);
                if (c.equals(targetColor)) { // found target color so click
                  robot.mouseMove(screenX, screenY);
                  robot.mousePress(InputEvent.BUTTON1_DOWN_MASK);
                  robot.mouseRelease(InputEvent.BUTTON1_DOWN_MASK);

                  Thread.sleep(1000); // Wait for 1 second (this has an uncaught exception, I just left it out to keep the example shorter)
                }
              }
            }
          }
        }
      }
     });

    frame.add(b);

    frame.setSize(200, 200);
    frame.setLayout(null);
    frame.setVisible(true);

    clientMainMethod.invoke(null, new Object[]{new String[0])); // start the client
  }
 }