import javax.swing.JTable;import javax.swing.table.AbstractTableModel;import javax.swing.JScrollPane;import javax.swing.JFrame;import javax.swing.SwingUtilities;import javax.swing.JOptionPane;import java.awt.*;import java.awt.event.*;public class TableDemo extends JFrame {    private boolean DEBUG = true;    public TableDemo() {        super("TableDemo");        MyTableModel myModel = new MyTableModel();        JTable table = new JTable(myModel);        table.setPreferredScrollableViewportSize(new Dimension(500, 70));        //Create the scroll pane and add the table to it.         JScrollPane scrollPane = new JScrollPane(table);        //Add the scroll pane to this window.        getContentPane().add(scrollPane, BorderLayout.CENTER);        addWindowListener(new WindowAdapter() {            public void windowClosing(WindowEvent e) {                System.exit(0);            }        });    }    class MyTableModel extends AbstractTableModel {        final String[] columnNames = {"First Name",                                       "Last Name",                                      "Sport",                                      "# of Years",                                      "Vegetarian"};        final Object[][] data = {            {"Mary", "Campione",              "Snowboarding", new Integer(5), new Boolean(false)},            {"Alison", "Huml",              "Rowing", new Integer(3), new Boolean(true)},            {"Kathy", "Walrath",             "Chasing toddlers", new Integer(2), new Boolean(false)},            {"Sharon", "Zakhour",             "Speed reading", new Integer(20), new Boolean(true)},            {"Angela", "Lih",             "Teaching high school", new Integer(4), new Boolean(false)}        };        public int getColumnCount() {            return columnNames.length;        }                public int getRowCount() {            return data.length;        }        public String getColumnName(int col) {            return columnNames[col];        }        public Object getValueAt(int row, int col) {            return data[row][col];        }        /*         * JTable uses this method to determine the default renderer/         * editor for each cell.  If we didn't implement this method,         * then the last column would contain text ("true"/"false"),         * rather than a check box.         */        public Class getColumnClass(int c) {            return getValueAt(0, c).getClass();        }        /*         * Don't need to implement this method unless your table's         * editable.         */        public boolean isCellEditable(int row, int col) {            //Note that the data/cell address is constant,            //no matter where the cell appears onscreen.            if (col < 2) {                 return false;            } else {                return true;            }        }        /*         * Don't need to implement this method unless your table's         * data can change.         */        public void setValueAt(Object value, int row, int col) {            if (DEBUG) {                System.out.println("Setting value at " + row + "," + col                                   + " to " + value                                   + " (an instance of "                                    + value.getClass() + ")");            }            if (data[0][col] instanceof Integer                                            && !(value instanceof Integer)) {                                  //With JFC/Swing 1.1 and JDK 1.2, we need to create                    //an Integer from the value; otherwise, the column                     //switches to contain Strings.  Starting with v 1.3,                   //the table automatically converts value to an Integer,                //so you only need the code in the 'else' part of this                 //'if' block.                                                          //XXX: See TableEditDemo.java for a better solution!!!                try {                    data[row][col] = new Integer(value.toString());                    fireTableCellUpdated(row, col);                } catch (NumberFormatException e) {                    JOptionPane.showMessageDialog(TableDemo.this,                        "The \"" + getColumnName(col)                        + "\" column accepts only integer values.");                }            } else {                data[row][col] = value;                fireTableCellUpdated(row, col);            }            if (DEBUG) {                System.out.println("New value of data:");                printDebugData();            }        }        private void printDebugData() {            int numRows = getRowCount();            int numCols = getColumnCount();            for (int i=0; i < numRows; i++) {                System.out.print("    row " + i + ":");                for (int j=0; j < numCols; j++) {                    System.out.print("  " + data[i][j]);                }                System.out.println();            }            System.out.println("--------------------------");        }    }    public static void main(String[] args) {        TableDemo frame = new TableDemo();        frame.pack();        frame.setVisible(true);    }}