The Anatomy of a Class

 

 

Class Members:

Methods

Methods define what an object can do or the behavior of the object.

Constructors

Constructors don’t actually construct the object. The class makes the object and then executes a constructor to initialize the values of the fields (instance variables).

Member Access Specifiers

The members of a class are classified into three categories: private, public, and protected. This chapter mainly discusses the first two types, private and public. In C++, private, protected, and public are reserved words and are called member access specifiers.

Following are some facts about public and private members of a class:

  • By default, all members of a class are private.

  • If a member of a class is private, you cannot access it directly from outside of the class.

  • A public member is accessible outside of the class.

  • To make a member of a class public, you use the member access specifier public with a colon, :

 

Object Diagram

Encapsulation

  • There are two views of an object:

    • internal  -  the details of the variables and methods of the class that defines it

    • external  -  the services that an object provides and how the object interacts with the rest of the system

  • From the external view, an object is an encapsulated entity, providing a set of specific services

  • These services define the interface to the object

 

COSC-1336 / ITSE-1302 Computer Science - Author: Dr. Kevin Roark