Unified Modeling Language(UML) BY

Touseef Tahir

Touseeftahir@ciitlahore.edu.pk

Lecturer CS

COMSATS Institute of Information Technology, Lahore

Unified Modeling Language(UML)BY

1

Overview

Introduction

History

Goals

Diagrams and Examples

Latest Changes

Disadvantages

Conclusion

What is UML?

Unified Modeling Language (UML) is a standard language for specifying, visualizing, constructing software artifacts.

Not necessarily restricted to software systems used in business modeling.

Has proven successful in modeling of large and complex systems.

Uses graphical notations to describe the architecture of software.

Goals

Provide users a expressive, visual language to enable sharing of meaningful models.

Enables developers to compare models before implementation phase.

Independent of programming language and development process.

Encourage growth of Object Oriented Tools market.

History

First modeling languages 1970s.

More than 50 modeling languages present during 1994. Lead to method wars.

Methods began to incorporate each others techniques.

In 1994, Grady Booch and Jim Rumbaugh (Rational Software Corporation) unified Booch and Object Modeling Technique methods to create UML.

Ivar Jacobson incorporated the OOSE method in 1995, leading to UML version 0.9 in late 1996.

UML Versions

UML 1.0 was created through a collaboration of various organizations: Microsoft, IBM, HP, etc.

Today, UML is on Version 2.0.

It is managed by the Object Management Group not for profit consortium. UML specification is available for download at http://www.uml.org/

Tools that conform the latest 2.0 specification Rational Software Architect, Sparx System Architect, Star UML, etc.

Types of UML diagrams

Class Diagram

Class diagram

Abstraction

Inheritance

Polymorphism

Encapsulation

Message Sending

Associations

Multiplicity

Aggregation

Class diagram

Inheritance

Generalization in UML

Inheritance (Cont..)

Aggregation

Two types of Association

Part-whole association

Composition

Aggregation

Part-whole association

Multiplicity

Aggregation

Multiplicity

Aggregation

Composition

A strong type of aggregation. Each component in composite can belong to just one whole.

The Diamond shape used for composition is same but its just filled.

Package

UML Packages are a grouping of objects into sets of objects that provide related services. The package has responsibilities that are strongly related.

Coupling & cohesion

Stereotype and comments

Generalization

State Diagrams

State Diagrams

State diagram

Behavior of systems

Finite number of states

Components of state diagram

State diagram

An objects state and behaviour can be affected by:

Changes to attribute values

Results of operations

Changes of links with other objects

Internal events

External events

Three models

Object model:

Static structure of objects in a system and their relationships.

Contains class diagrams.

dynamic model;

describes aspects that change over time: state transition diagrams

functional model;

Use Case diagrams

State and Events

A state is an abstraction of the attribute. Sets of values are grouped together into a state according to properties that affect the gross behaviour of the object.

A change of state is called a transition

Event classes

Event occurrences are grouped into event classes

Flight 123 departs from Chicago / Flight 456 departs from Rome

Event class is Flight Departs

Attributes of event classes

Departure origin of flight

Flight number

destination

Data values are Attributes

Event Classes and Attributes

Aeroplane flight departs (airline, flight no, city)

Mouse button pushed (button, location)

Input string entered (text)

phone receiver lifted( True, False)

digit dialled (digit)

engine speed enters danger zone

Events

Something that happens at a point in time

Mouse button clicked / Signal changes

Logically ordered events - causally related

Concurrent events - causally unrelated

do not effect each other

there is no order between them

1-way transmission of information from one object to another

Characterisations of a state

State: Alarm ringing

Description: alarm on watch is ringing to indicate target time

Event sequence that produces the state:

set alarm (target time)

any sequence not including clear alarm

current time = target time

How to make state diagram

Identify states and identify which variables identify states

Identify events

Create state chart

Create state table with all finite stated and event

Example

ExampLe

State Transition Diagram

Idle

Dial tone

do : Sound dial tone

do : Sound dial tone

Connecting

do : find connection

do : find connection

ringing

do : ring bell

do : ring bell

Connected

Disconnected

Busy tone

do : slow busy tone

do : slow busy tone

Fast busy tone

do : play fast busy tone

do : play fast busy tone

Time out

do : sound loud beep

do : sound loud beep

Recorded message

do : Play message

do : Play message

Dialling

off-hook

routed

called phone answers

/connect line

called phone hangs up

/disconnect line

on-hook

time-out

digit (n)

time-out

message done

digit (n)

valid number

invalid number

trunk busy

on-hook/

disconnect line

number busy