JFormattedTextField, Document Filter, Document Listener

He everyone I have been looking around for a long time to answer this quesiton.
I have looked at a lot of website and fourms , the API and Oracle tutorials but still to no avail
My question is :

I'm looking for a way to change something that is entered into a textfield
in a lot of point of sale terminals when you enter an amount of cash it places the . for you.
i also want to do this
i want it start in the text field as 0.00
if the user enters 7 it will become 0.07
if the use next enters 6 it will become 0.76
the if they next enter 3 it will become 7.63
and so on and so forth

any help or coding on this would be very helpful it is the last piece of the puzzle for my piece of software

Thank you in advance

Moved from New to Java.

Might be possible with a DocumentFilter and some fancy coding. Take a try and post your best efforts, in the form of a SSCCE (Short, Self Contained, Compilable and Executable) example.

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