Relative positioning of windows

Question

I need class B, which is called from class A to appear at the same coordinates as A when it is called. I've included code below, can anyone tell me where I'm going wrong? Which is the best way to do it?
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JComponent;
public class A extends JPanel {
     public JFrame aFrame;
     public int x=aFrame.getX();
     public int y=aFrame.getY();
     public static void main(String[] args) {
         javax.swing.SwingUtilities.invokeLater(new Runnable() {
             public void run() {
                 A a = new A();
                 new B();
    public A()
        aFrame = new JFrame("A");
        aFrame.setSize(400,400);
        aFrame.setLocationRelativeTo(null);     //centres frame on screen
        aFrame.setLocation(10,10);
        aFrame.getContentPane().add(addFormComponents());
        //Display the window.
        aFrame.pack();
        aFrame.setVisible(true);
    public JComponent addFormComponents()
         JPanel form = new JPanel();
         //     add stuff here
         return form;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JComponent;
public class B extends A {
     public JFrame frame;
    public B()
        frame = new JFrame("B");
        frame.setSize(400,400);
        //JComponent c=aFrame;
        //frame.setLocationRelativeTo(aFrame.getX(), aFrame.getY());
        //frame.setLocationRelativeTo(c);
        frame.setLocation(x,y);
        frame.getContentPane().add(addFormComponents());
        //Display the window.
        frame.pack();
        frame.setVisible(true);
    public JComponent addFormComponents()
         JPanel form = new JPanel();
         //     add stuff here
         return form;
}

Answer 1

Initialize the x and y after aFrame.setLocation
i.e.
public class A extends JPanel {
public int x;
public int y;
public A()
        aFrame = new JFrame("A");
        aFrame.setSize(400,400);
        aFrame.setLocationRelativeTo(null);     //centres frame on screen
        aFrame.setLocation(10,10);
        x=aFrame.getX();
         y=aFrame.getY();
        aFrame.getContentPane().add(addFormComponents());
        //Display the window.
        aFrame.pack();
        aFrame.setVisible(true);
    }In your original code after getting the value of x and y you are changing the position of A. For this your B is not coming in the same co-ordibate
Hope it helps :)