Class diagrams are used to depict the system's static perspective. They are used in the design process to show the shared roles and responsibilities of the entities that produce the behavior of the system.

Class diagrams are widely used in the modeling of object-oriented designs because this is the only UML diagram that can be directly transferred to object-oriented programming languages.

Why use class diagrams?

The following are some important purposes of the class diagram:

  • Represents the system's static structure.

  • Directly maps with object-oriented languages.

  • Represents what the system's duties or responsibilities are.

  • Uses in both forward and reverse engineering.

Popular notations in the class diagram

The following are some essential notations of the class diagram:

  • Class notation

  • Interface, abstract class, and enumeration

  • Access modifiers

Class notation

A class is represented by a rectangle with three sections. The first section holds the class name, the second one lists the attributes, and the third one shows the methods (operations). The following is the depiction of a `Movie` class with its attributes and methods.

Level up your interview prep. Join Educative to access 80+ hands-on prep courses.