Extend DefaultListModel to create an array based model for JList in Java

  /*w  ww  . j a  v  a2s .c o m*/

import java.awt.BorderLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.DefaultListModel;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JScrollPane;

class MyListModel extends DefaultListModel {
  protected int[] count = new int[100];

  public Object getElementAt(int index) {
    if (index < 100) {
      count[index]++;
    }
    return super.elementAt(index);
  }

}
public class Main extends JFrame {
  MyListModel model = new MyListModel();

  public Main() {
    for (int i = 0; i < 25; i++) {
      model.addElement("A" + i);
    }
    JList list = new JList(model);
    getContentPane().add(new JScrollPane(list), BorderLayout.CENTER);

    addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });

    pack();
    setVisible(true);
  }

  public static void main(String arg[]) {
    new Main();
  }
}