UML Class Diagrams

UML Class Diagrams
An Introduction

Prof. David Bernstein
James Madison University

Computer Science Department

bernstdh@jmu.edu

UML Class Diagrams

The Basics

Visibility

An Example

Static Members, Final Attributes, and Constants

An Example (cont.)

Associations

Definition:
- Class A is said to be associated with class B if an object in class A can send a message to an object of class B or if an object in class A can create, receive or return objects of class B.
Components:
- Name and/or Role
- Multiplicity

Associations (cont.)

Dependencies

Definition:
- Class A is said to depend on class B if a method in an object of class A is passed an object of class B.
Dependency or Association?
- A dependency is a special types of association

Dependencies (cont.)

Aggregations

Definition:
- An object of class A is an aggregate of ("has") objects of class B if an object of class B is a part of an object of class A.
Obvious Applications to Collections:
Less Obvious Applications: