What do you want to do, format or parse a date? It seems like you might be confusing the two. Formatting means converting a Date object to a string. Parsing is the opposite: converting a string into a Date object.
A Date object represents a moment in time. It doesn't have any format by itself. To display a Date object, you must convert it to text (a string). For this, you use a DateFormat object. Class SimpleDateFormat is a subclass of DateFormat that allows you to specify how you want the Date object to be converted to a String.
If you want it with the format "dd/MM/yyyy", you can do this:
If you print a Date object directly, like this:
Then what happens is that toString() is called on the Date object, which formats the date with a default format string, so that you get something like "Mon Jul 13 15:15:23 IDT 2009".
Make sure that you understand what a Date object is exactly and what formatting and parsing mean.