Why do we need a private constructor?

Question

If a class has a private constructor then it can\'t be instantiated. So, if I don\'t want my class to be instantiated and still use it, then I can make it static.

Wh

Answer 1

Well if your only objective is that you don't want it to be instantiated, then making it static is sufficient.

If, otoh, you simply don't want it to be instaniated frm outside the class, (maybe you only want users to get one by using a static factory on the class) - then you need a private ctor to allow those publicly accessible static factories to instantiate it.

Historically, remember that making a class static has not always been around... Making the ctor private was a way to make it not-instantiatable (is this a word? ) before the static keyword could be applied to a class...