Sparsely Populated Table Model : JTable Model « Swing « Java Tutorial

Sparsely Populated Table Model
import java.awt.BorderLayout;
import java.awt.Point;
import java.util.HashMap;
import java.util.Map;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.TableModel;

class SparseTableModel extends AbstractTableModel {

  private Map<Point, Object> lookup;

  private final int rows;

  private final int columns;

  private final String headers[];

  public SparseTableModel(int rows, String columnHeaders[]) {

    this.rows = rows;
    this.columns = columnHeaders.length;
    headers = columnHeaders;
    lookup = new HashMap<Point, Object>();

  public int getColumnCount() {
    return columns;

  public int getRowCount() {
    return rows;

  public String getColumnName(int column) {
    return headers[column];

  public Object getValueAt(int row, int column) {
    return lookup.get(new Point(row, column));

  public void setValueAt(Object value, int row, int column) {
    if ((rows < 0) || (columns < 0)) {
      throw new IllegalArgumentException("Invalid row/column setting");
    if ((row < rows) && (column < columns)) {
      lookup.put(new Point(row, column), value);

public class SparseTableModelDemo {
  public static void main(String[] a) {

    String headers[] = { "A", "B" };
    TableModel model = new SparseTableModel(10, headers);
    JTable table = new JTable(model);
    model.setValueAt("1", 0, 0);
    model.setValueAt("2", 9, 0);
    model.setValueAt("3", 5, 1);
    model.setValueAt("4", 8, 1);

    JFrame frame = new JFrame("Fixed Column Table");

    frame.add(new JScrollPane(table), BorderLayout.CENTER);
    frame.setSize(300, 150);

14.59.JTable Model
14.59.1.Create DefaultTableModel
14.59.2.Creating simple JTable using AbstractTableModel
14.59.3.Extending AbstractTableModelExtending AbstractTableModel
14.59.4.Creates tables that allow rows and columns to be added or deleted
14.59.5.Set table valueSet table value
14.59.6.Add logic to get value methodAdd logic to get value method
14.59.7.Subclass AbstractTableModel to reuse an existing data structure: Treat an array as an AbstractTableModelSubclass AbstractTableModel to reuse an existing data structure: Treat an array as an AbstractTableModel
14.59.8.Sparsely Populated Table ModelSparsely Populated Table Model
14.59.9.Listening to JTable Events with a TableColumnModelListenerListening to JTable Events with a TableColumnModelListener
14.59.10.The Calendar program.The Calendar program.
14.59.11.Sample Sorting Table ModelSample Sorting Table Model
14.59.12.Add columns to a table through DefaultTableModel
14.59.13.Insert a row to a table through DefaultTableModel
14.59.14.Insert a row to a table through DefaultTableModel at specified row
14.59.15.Append a row to a table through DefaultTableModel at specified row
14.59.16.Remove the first row from a table with DefaultTableModel
14.59.17.Remove the last row from a table with DefaultTableModel
14.59.18.Move the first row to the end of the table
14.59.19.Move the first two rows to the end of the table
14.59.20.Move the last two rows to the start of the table
14.59.21.Move the last row to the beginning of the table
14.59.22.Get all the table data from DefaultTableModel
14.59.23.Copy (clone) the data from the second row
14.59.24.Overwrite the date from the first row with DefaultTableModel
14.59.25.Add rows to a Table
14.59.26.Sharing a Table Model Between JTable Components
14.59.27.Disabling User Edits in a JTable with DefaultTableModel
14.59.28.Appending a Row to a JTable Component
14.59.29.Copy data from a table to a list
14.59.30.Map TableModel
14.59.31.Bean Property Table Model