1. Chapter 6:
Structured Vs.
Object Oriented Analysis and Design

2. Overview Why do we need Modelling ”Blue prints” ?
Object Oriented Analysis and Design (OOAD) vs. Structured Oriented Analysis and Design (SAD).
Steps to SAD and OOAD.
Object Oriented Analysis and Design - OOAD.
Unified Modelling Language - UML.

3. By the end of this chapter, you will..
Understands what Structured Analysis and Design is.
Understands what Object Oriented Analysis and Design is.
Understands what is Unified Modeling Language “UML” and the UML models.
Distinguishes between the analysis oriented and design oriented.

4. The Need for Software Blueprints
Knowing an object-oriented language and having access to a library is necessary but not sufficient in order to create object software.
In between a nice idea and a working software, there is much more than programming.
Analysis and design provide software “blueprints”, illustrated by a modeling language.
Blueprints serve as a tool for thought and as a form of communication with others.
These blueprints can then be transferred into code using any specific OO language.

5. Object Oriented Analysis and Design (OOAD) Vs
Object Oriented Analysis and Design (OOAD) Vs. Structured Analysis and Design (SAD)
OO Analysis expresses Requirements and Specs expressed as
Population of interacting objects of a system
as opposed to
The traditional data or functional views.

6. OOAD Vs. SAD OOAD SAD Library System Record Loans Add Resource
Report Fines
OOAD
SAD
Catalog
Librarian
Book
Library

7. OOAD Vs. SAD Structured Analysis Divide and Conquer
At the function level
Object-Oriented Analysis
Partition
At the level of concepts (objects)

8. OOAD Vs. SAD

9. OOAD Vs. SAD Structured Approach Use Case Diagram Context level DFD
Subsequent levels DFDs
ER Diagram if needed
DB Schema & Dictionary
Architectural Design
Structured Tables/Decision Trees/Flowcharts ( for major processes only) (Component Design)
Interface design
Object-Oriented Approach
Use-case Diagram
Use-cases’ descriptions (expanded for major use cases only)
Conceptual Diagram
Sequence Diagrams
Class Diagram
ER Diagram if needed
DB Schema & Dictionary
Architectural Design
Pseudo code/Algorithms/Flowcharts (Component Design)
Interface design

10. Object Oriented Analysis
OOAD essential for creating well-designed, robust & maintainable software system using OO Programming Language (e.g. C++, Java, smalltalk, etc…).
It is the latest and most used way of design now.
UML (Unified Modeling Language) is a modeling language for OOS.
An investigation of the problem (rather than how a solution is defined).
During OO analysis, there is an emphasis on finding and describing the objects (or concepts) in the problem domain.
Example: Concepts in a Library Information System include; Book and Catalog.

11. Object Oriented Design
Emphasizes a conceptual solution that fulfills the requirements specified in the analysis.
Need to define software objects and how they collaborate to fulfill the requirements.
Designs are implemented in a Programming Language.
Example: in the Library Information System, a Book software object may have a title attribute and a display() method. And implemented using any OO programming language; e.g. Java.

12. Logical Software Objects
From Analysis to Implementation
Analysis
Investigation of the problem
Design
Logical Solution
Construction
Code
Representation in an
OO Programming Language
Public Class Book {
Private String Title;
Public void Display(); }
Logical Software Objects
Domain Concept
Ex: Book (Concept)
Book
Attribute: Title
Method: Display()

13. Unified Modeling Language
A notational system aimed at modeling systems using object oriented concepts.

14. 3-Collaboration Diagrams
Steps to OOAD
1-Define use cases
2-Conceptual Model
3-Collaboration Diagrams
4-Design Class Diagram

15. More Analysis Oriented
Analysis and Design Activities
More Analysis Oriented
More Design Oriented
Design Oriented
How
Logical Solution
Analysis Oriented
What
Requirements
Investigation of Domain