C++ Objects and Scope

Important Definitions  Class  Access and Visibility  Encapsulation  Unified Modeling Language (UML)  Constructor  Destructor  Scope

Class Definitions  A Class is a blueprint for an object. It holds a recipe for making/using an object

Access Specifies  Items inside of a class can be set to be accessible only by objects of that class or by anyone  A public member can be accessed (using an object of the class1) anywhere in a program that #includes the class definition file.  A protected member can be accessed inside the definition of a member function of its own class, or a member function of a derived class.  A private member is only accessible by member functions of its own class.

Encapsulation  Encapsulation is the term used to describe how an object contains its own data and functions for manipulating that data.  Encapsulation lets an object be 'self- sufficient'

Unified Modeling Language (UML)  A graphical way of seeing a class and its associated data elements and methods/functions. Figure from course text

Constructors  Every object when its created runs a 'constructor' function  A class can have different constructors at the same time based on different needs

Destructors  Every object when it is destroyed runs a 'destructor' function  Destructors keep memory clean  They can handle IO operations (closing files or ports)

Scope  Scope™ is a mouthwash  Scope is where variables and function exist in code.  Something 'out of scope' can not be accessed or manipulated  The main method of defining scope is { and }

In Summary  Classes describe objects  Classes show what is 'encapsulated' in an object  All classes have constructors and destructors.