What is the use of package level protection in java?

Question

I know how package level protection in java works. I read a lot of code (including lots of open source stuff) and no-one seem to be using it. The whole protection l

Answer 1

In my opinion, package-private (default) access for methods and fields is useless. In fact, it's worse than useless, it's harmful since it's typically used to provide access to some member that ought to be private but isn't for reasons of convenience.

However, package-private classes are useful. You may want to provide an implementation of an interface using a package-private class. A factory method might be declared to return an object that implements a given interface. In this situation, it is not important to know which class is providing the implementation for the interface. By making the class package-private, it is not part of the public API and therefore can be modified or replaced in future versions.

In Oak, the language that later became Java, there were only 3 access levels.

If I were redesigning Java now, I would get rid of the current default (package-private) and make private the default. A private class would be one that is private within its enclosing scope (the package), which would work exactly how package-private classes work already and be more consistent with the use of 'private' for members.