import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
class Elenco extends JFrame 
{ private JList lista;
	private JLabel etic;
	Elenco(Object[] oa) 
	{	super("Esempio elenco");
		lista = new JList(oa);
		getContentPane().add(lista);
		etic = new JLabel("Scegli");
		getContentPane().add(etic, BorderLayout.SOUTH);
		lista.addListSelectionListener(new Ascoltatore());
		lista.setSelectionMode
							(ListSelectionModel.SINGLE_SELECTION);
		setDefaultCloseOperation(DISPOSE_ON_CLOSE);
	}
	public class Ascoltatore 
					 implements ListSelectionListener 
	{	public void valueChanged(ListSelectionEvent e)
		{	Object o = lista.getSelectedValue();
			etic.setText(o.toString());
		}
	}
}

public class ProvaElenco
{ public static void main(String[] args)
	{	String[] list = {"uno", "due", "tre", "quattro"};
		Elenco el = new Elenco(list);
		el.setSize(200, 200);
		el.setVisible(true);
	}
}