UML Basics

UML = Unified Modelling Language
UML Models
  • Business System Model (BSM)
  • IT System Model (ISM)
UML Views
  • BSM
    - External view
    - Internal View
  • ISM
    - Static view
    - Dynamic view
UML Diagrams
  • Class diagram
    • classes within the system
    • methods and fields
    • associations, generalizations and cardinality
  • Component diagram
    • components of the system
    • contains implemented and required interfaces
    • components can be nested
  • Sequence diagram
    • shows call sequence
    • shows the calling class, called method and returned data type
    • can show loops
  • State diagram
    • shows states or activities
    • shows allowed transitions
    • can be nested
    • can depict internal activities
  • Activity diagram
    • modern flowcharts
    • shows process or workflow
    • can be nested
    • can show concurrent actions
    • can have swim lanes
  • Layer diagram
    • Microsoft specific (non-standard, invented by MS)
    • shows areas of concern
    • show references between areas
    • can be validated
  • Use Case diagram
    • show actors
    • shows use cases
    • binds actors to use cases
    • can depict generalizations