public void setValueAt(Object value, int row, int col) {
        // if (DEBUG) {
        if (value != null) {
            if (MainFrame.DEBUG) {
                System.out.println("Setting value at " + row + "," + col
                        + " to " + value
                        + " (an instance of "
                        + value.getClass() + ")");
            }
            //}

            data[row][col] = value;
            fireTableCellUpdated(row, col);


            if (MainFrame.DEBUG) {
                System.out.println("New value of data:");
                printDebugData();
            }
        }
    }