Java Swing How to - Extend AbstractListModel to create custom list model

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Question

We would like to know how to extend AbstractListModel to create custom list model.

Answer

//from w  w w. j  a v a  2 s.c om
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;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

public class LongListTest extends JFrame implements ListSelectionListener {
  JLabel label = new JLabel();

  public LongListTest() {
    setTitle("LongListTest");
    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);

    wordList.setFixedCellWidth(50);
    wordList.setFixedCellHeight(15);

    JScrollPane scrollPane = new JScrollPane(wordList);

    JPanel p = new JPanel();
    p.add(scrollPane);
    wordList.addListSelectionListener(this);

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

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

  public void valueChanged(ListSelectionEvent evt) {
    JList source = (JList) evt.getSource();
    String word = (String) source.getSelectedValue();
    label.setText(word);
  }

  public static void main(String[] args) {
    JFrame frame = new LongListTest();
    frame.show();
  }
}

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);
  }
}

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