I have 2 JLists. How can I find which JList user clicked?

Below is the code. It can move the names from
the left to the right if you click the name. How can I move the name
from the right to left? Thank you very much.

import java.awt.*;
import javax.swing.event.*;
import javax.swing.*;

public class List2 implements ListSelectionListener
{
JList l1,l2;
DefaultListModel model1 = new DefaultListModel();
DefaultListModel model2 = new DefaultListModel();
  public static void main(String[] args) {
    JFrame f = new JFrame("Lister v1.0");
    List2 l=new List2();
    f.setSize(200, 200);
    f.setLocation(200, 200);
        Container c = f.getContentPane();
        GridLayout grd = new GridLayout(1,2,10,10);
        c.setLayout(grd);
    l.create();
    c.add(l.l1);
        c.add(l.l2);
    f.setVisible(true);
      }

public void valueChanged(ListSelectionEvent e){
        Object selection = l1.getSelectedValue();
        if (l1.getSelectedIndex()>=0){
            model2.addElement(selection);
            model1.removeElementAt(l1.getSelectedIndex());
    }}

private void create(){
        l1 = new JList(model1);
        l2 = new JList(model2);
        model1.addElement("Mark");
        model1.addElement("Mary");
        model1.addElement("Mike");
        l1.addListSelectionListener(this);
  }}