JTable model getColumnClass() problem

Im extending DefaultTableModel with a class called MyTableModel. In this class I define the method getColumnClass() so that boolean values will be rendered as Check boxes

public Class getColumnClass(int c) {

return getValueAt(0, c).getClass();

}

the problem is, I get NullPointerExceptions when loading my model data because in some cases getValueAt(0, c) is null

I can just null check in getColumnClass, but then i dont know what to return

Any swing pros know how to overcome this problem

[534 byte] By [jes1789a] at [2007-10-2 11:35:38]