System analysis 2 OOP principles

definitions memory maker

Object-Oriented Analysis (OOA)

The first technical activity in object-oriented software engineering, focusing on understanding the problem.

OOA Principle: Information Domain

The system's information is modeled to understand its structure.

OOA Principle: Behavior

The system's reactions to stimuli are represented.

OOA Principle: Function

Describes the functionality within the system.

OOA Advantage: Data Focus

Emphasizes data over procedures, unlike Structured Analysis.

OOA Advantage: Modularity

Helps manage software complexity using modular design.

Object Modeling

Develops static structure through objects, classes, and relationships.

Dynamic Modeling

Describes how objects respond to internal/external events over time.

Dynamic Modeling Step: State Transition Diagrams

Diagrams showing object states and transitions.

Functional Modeling

Shows internal processes and data changes within an object.

Object Model Benefit: Reusability

Supports reuse of objects, designs, and functions.

Object-Oriented Design (OOD)

Converts analysis models into detailed design models.

OOD Layer: Subsystem Layer

Defines major components to meet user requirements.

OOD Layer: Class & Object Layer

Represents class hierarchies and objects.

OOD Layer: Message Layer

Handles communication between objects.

OOD Layer: Responsibilities Layer

Specifies attributes and operations of objects.

Object-Oriented Programming (OOP)

A model centered around objects rather than logic.

OOP Benefit: Collaboration

Supports team development via modular design.

Class

Blueprint for objects; defines attributes and methods.

Object

Instance of a class with unique attributes and behavior.

Method

A function within a class defining object behavior.

Attribute

Stores the object's state; defined in the class.

Subclass

Inherits from a superclass; specializes behavior.

Superclass

Base class with shared attributes and methods.

Association

Relationship showing communication between classes.

Multiplicity

Indicates number of objects in a relationship.

Associative Class

Association with attributes or relationships.

Generalization

Combines shared traits into a superclass.

Aggregation

Whole-part relationship; parts can exist independently.

Composition

Strong aggregation; parts die with the whole.

Encapsulation

Bundles data and methods; restricts outside access.

Abstraction

Hides internal details, shows only essential parts.

Inheritance

Reuses logic by deriving new classes from existing ones.

Polymorphism

Objects share behaviors and take multiple forms.

Bottom-Up Approach

Builds systems from detailed parts to the whole.

OOP Feature: Reusability

New classes can extend existing ones.