The class members like variables, methods and constructors declared as protected access modifier in a super-class can only be visible to the  subclasses in other package.

The protected access modifiers are restricted  to outer-class and interfaces; however the access modifiers are applicable to the nested or inner class like an umbrella.  The methods and fields in a interface cannot be declared protected.

In this regard a private access modifier in an inner or nested class, delimits the outer classes.

Protected access gives the subclass a chance to use the helper method or variable, while preventing a nonrelated class from trying to use it.