Extend AbstractListModel to create custom list model for JList in Java

//from  w w  w  . j a v a  2s .  co m
 
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.AbstractListModel;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;

public class Main extends JFrame {
  JLabel label = new JLabel();

  public Main() {
    setSize(400, 300);
    addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });

    JList wordList = new JList(new WordListModel(300000));
    wordList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

    JScrollPane scrollPane = new JScrollPane(wordList);

    JPanel p = new JPanel();
    p.add(scrollPane);

    getContentPane().add(p, "Center");

    getContentPane().add(label, "North");
  }

  public static void main(String[] args) {
    JFrame frame = new Main();
    frame.setVisible(true);
  }
}

class WordListModel extends AbstractListModel {
  private int length;

  public WordListModel(int n) {
    length = n;
  }

  public int getSize() {
    return length;
  }

  public Object getElementAt(int n) {
    return Integer.toString(n);
  }
}