Access Control

Access Control

C++ has a third access specifiers or visibility mode called protected. This access specifiers protected plays an important role in inheritance. A member declared as protected is accessible by member function in its class or any class derived from its own class objects can never access private and protected member of a class directly. On the other hand, objects can reach these members through the public member functions in the class.

            There are three kinds of functions accessing a class: functions implementing the class (its friends and members), functions implementing a derived class (the friends of derived class and members) and other functions. A member of a class can be private, protected or public.

If a member is private, only member functions and friends of the class in which it is declared can use its name.

If it is protected only member functions and friends of the class in which it is declares and by member functions and friends of classes derived from this class can be use its name.

If a member is public, its name can be used by any function.

Access specifiers	Member functions and friends	Derived class member functions and friends	General users
Public	Yes	Yes	Yes
Protected	Yes	Yes	No
Private	Yes	No	No

Other Recommended posts

• Introduction
• Access Controls
• Types of Derivations
• Classification of Inheritance
• Single Inheritance
• Multilevel Inheritance
• Hierarchical Inheritance
• Multiple Inheritance
• Hybrid Inheritance
• Virtual Base Class
• Derived Class Construction and Destructor