[java] Sill constructors which don't work

public class d extends JFrame
{
	
	JList list1 = new JList();
	JList list2 = new JList();	
		
	d()
	{
		Container cont = getContentPane();
		JPanel pane = new JPanel();
		
		pane.add(list1);
		pane.add(list2);
		cont.add(pane);
		
		list1.setListData(RPG.a.a);
		list2.setListData(RPG.b.b);
		
		list1.updateUI();
		list2.updateUI();
		
	}
	
	public static void main(String[] args)
	{
		d frame = new d();
		frame.setVisible(true);
		frame.pack();
		frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
	}
	
	
	
}

class a
{
	static String a[] = new String[1];
	
	a()
	{
		a[0] = "F";
	}
	
	
}

class b
{
	static String b[] = new String[1];
	
	b()
	{
		b[0] = "A";
	}
	
}