Questions About JTable Cell Editing?

[RC]

I am try to edit my table three columns:

Observation Time, Value and Mode where they are
Timestamp, Double and String.

My first question is do I need to create three
different DefaultCellditors, one for Timestamp, one
for Double and one for String?

Because I am thinking use JFormattedTextField instead just JTextField,
which I can force user type in correct Timestamp format and Double
digits.

I went to this page

http://java.sun.com/docs/books/tutorial/uiswing/components/table.html

But I couldn't find some sample codes.
I also checked out Sun's TableDemo.java in SwingSet2. I only
found JComboBox CellEditor codes.

Can someone out there point me some sample codes how to create
some table cell editor?
Thank Q very much in advance!