I will end up obtaining a String,but all I need is simply to convert an object of one type(String) to another one(Date)
Your code does exactly that, convert a String to a Date object. What is it that you don't understand?
If you print the Date object after parsing it by just doing a System.out.println(d); then the Date will ofcourse be converted back to a string automatically, because it needs to be in a string format to be displayed on the screen. If you don't specify how the Date object should be formatted, then the toString() method of class Date is called automatically which uses a default format, so that you get:
Mon Jan 24 00:07:00 BRT 1983
Do you understand that a Date object is just a Date object - it doesn't have any implicit formatting.