UML

Unified Modeling Language

Within the Information Technology world, It is useful to ¨model¨ in simple drawings a system of software.

The basis of this modeling language in the software context is the Object Oriented Programming paradigm.

Object Oriented concepts in detail

• Objects
  • Represents something in the real or "unreal" world, for example
    • Ball
    • House
    • Triangle
• Class
  • Is the blue print of an object, a sort of squeleton that will be used when a new object is created
• Abstraction
  • Represents the Behavior of an entity
    • For example in the context of a Ball
      • All balls rolls
• Encapsulation
  • A mechanism that shield the properties of an object and provides an API in order to access or modify them
• Inheritance
  • A mechanism of reutilization and relationship among objects
    • Sample
      • An object of type Bar tender inherits from the class Employee, since every bar tender is an employee
• Polymorphism
  • A mechanism through which an object that inherits other can impersonate it

The purpose of Object Oriented Programming Analysis and Design

• Identifying the objects of a system
• Identify their relationships
• Make a design that can be converted to executables using OO languages

So the stages are

1. Analysis
2. Design
3. Implementation

UML Building Blocks

Those are

• Things
• Relationships
• Diagrams

Things

• Structural
  • ​Static part of the UML
    • Class
    • Interface
    • Collaboration
      • Define interaction between elements
    • Use Case
      • Set of actions performed by a system for a specific goal
    • Component
      • Describe physical part of a system
    • Node
      • Physical element that exists at run time
• Behavioral
  • Dynamic part of the UML
    • Interaction
      • Message
    • State machine
      • Define the sequence of state an object goes through in response to events
• Grouping
  • Package
    • Gather structural and behavioral things
• Annotational
  • Note
    • Used to comments and notes

Relationships

• Dependency
  • A relation between two things in which change in one element affect the other
• Association
  • Set of links that connects elements of a UML model and describes how many object are  taking part in that relationship
• Generalization
  • Describe Inheritance, which is the connection among a specialized element with a generalized one
• Realization
  • Describe interfaces, which is the connection among an element that defines behavior and other that implements it

Diagrams

• Class Diagram
• Object Diagram
• Use Case Diagram
• Sequence Diagram
• Collaboration Diagram
• Activity Diagram
• Statechart Diagram
• Deployment Diagram
• Component Diagram

UML Architecture

There are 4 concepts that center their attention in a Use Case, which represents a given functionality

• Design
  • Define the collaboration of entities
• Implementation
  • Define which components make the whole system
• Process
  • Define the flow of the system
• Deployment
  • Define and represent the physical nodes of the system

Types of UML modeling

• Structural Modeling
  • Gather the static features
    • Class diagram
    • Object diagram
    • Deployment diagram
    • Package diagram
    • Composite structure diagram
    • Component diagram
• Behavioral Modeling
  • Define the interaction in the system, shows the dynamic nature of the system
    • Activity diagrams
    • Interaction diagrams
    • Use case diagrams
• Architectural Modeling
  • Represents the overall framework of the system. It contains both structural and behavioral elements.
  • Considered as the blue print of the entire system
  • Package diagram lies in this category