OOSDLab03-The Movement to Objects

7/31/2019 OOSDLab03-The Movement to Objects

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Systems Analysis and Design with UML 2.0, Third Edition

THE MOVEMENT TO OBJECTS


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Objective

Understand the basic characteristics of object-oriented systems

Be familiar with the Unified Modeling Language (UML) Version 2.0

Be familiar with the Unified Process


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Basic Characteristics of Object-Oriented

Systems

Classes and Objects

Methods and Messages

Encapsulation and Information Hiding

Inheritance

Polymorphism and Dynamic Binding


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Basic Characteristics of Object

Oriented Systems (Cont.)

An Object is a thing (person, place, etc) which we want to capture

information

An Object has attributes that describe information about the object

Objects are grouped into classes (collections of objects that share

common attributes and methods)


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Basic Characteristics of Object

Oriented Systems (Cont.)

Hierarchy of classes helps reducing redundancy in development

An Object has behaviors which are described by methods that

specify what an object can do

Objects communicate by sending messages which trigger methods


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Classes and Objects

Class Template to define specific instances or objects

Object Initiation of a class

Attributes Describe the object

Behaviors Specify what can object do


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Classes and Objects (Cont.)


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Methods implement an object behavior

Analogous to a function or procedure

Messages are sent to trigger methods

Procedure call from one object to the next


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Encapsulation and Information Hiding

Encapsulation combination of data and

process into entity

Information Hiding only the information

required to use a software module is published to

user

Reusability Key use an object by calling

methods


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Inheritance

Superclasses or general classes are at the top

of hierarchy of classes

Subclasses or specific classes are at the botom

Subclasses inherit attributes and methods

from classes higher in the hierarchy


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Inheritance (Cont.)


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Inheritance (Cont.)


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Polymorphism and Dynamic Binding

Polymorphism

a message can be interpreted differently by different

classes of objects

Dynamic Binding

Sometimes call late binding

Delays typing or choosing a method for an object until

run-time


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Polymorphism and Encapsulation

(Cont.)


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Object-Oriented System Analysis and

Design

Use-case driven

Architecture Centric

Iterative and Incremental

The Unified Process


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Before the UML

Evolution of OO Development Methods

1960s 1970s

COBOL, FORTRAN, C

Structured Analysis and Design Techniques

1980s early 1990s

Smalltalk, Ada, C++, Visual Basic

Early generation OO methods

Mid/ Late 1990s

Java

UML

Unified Process


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UML Version 2.0

Broken into two major groupings

Structure Diagrams

Behavioral Diagrams

Developers

Grady Booch

Ivar Jacobson

James Rumbaugh


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UML 1.4 VS UML 2.0

No. UML 1.4 Model Element Name UML 2.0 Model Element Name

1 Association end Member end and Property

2 Object (when used in activity diagrams) Object node

3 Object (when used in sequence diagrams) Lifeline

4 Collaboration diagrams Communication diagrams

5 Swimlane (or partition) ActivityPartition

6 Activity Structured activity node

7 Decision Decision node or merge node

8 Final State or end state Final Activity Node

9 Initial state or start state Initial node

10 Object Instance (in activity diagrams) Central buffer node

11 State Structured activity node

12 State machine Structured activity node

Source: http://publib.boulder.ibm.com/infocenter/rtnlhelp/v6r0m0/index.jsp?topic=/com.ibm.xtools.modeler.doc/topics/r_uml_name_diffs.html


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UML 1.4 VS UML 2.0 (Cont.)


13 Synchronization bar (synch bar) Fork node or Join node

14 Transition (on an activity diagram) Control flow

15 Transition condition (guard condition) Control flow guard

16 Formal Argument Template Parameter Substitution

17 Formal Arguments (collection of Formal

Arguments)

Template Binding

18 Three-tiered diagrams Class diagrams

19 Class Instance Lifeline

20 Self-link Message pathway

21 Connection relationship Communication Path

22 Process (in a deployment diagram) Artifact

23 Processor Execution environment

24 Destruction marker Stop node



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UML 1.4 VS UML 2.0 (Cont.)


25 Focus of Control Execution Occurrence

26 Action UML activity

27 - Composite Structure Diagram

28 - Interaction Overview Diagram

29 - Timing Diagram



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Structure Diagrams

Class

Object

Package

Deployment

Component

Composite Structure


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Structure Diagrams (Cont.)

Class

Relationships between classes

Object

Relationships between objects

Package

Group UML elements together to form higher level

constructs


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Structure Diagram (Cont.)

Deployment

Show the physical architecture and software

components of system

Component

Physical relationships among software components

Composite Structure

Illustrates internal structure of class


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Behavioral Diagrams

Activity

Illustrates business workflows

Interaction Diagrams

Sequence Time-based ordering behavior of objects activities in usecase

Communication Communication among a set of collaborating objects on an activity

Interaction Overview

Overview of flow of control of a process Timing

Illustrate the interaction and state changes which they go throughtime


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Behavior Diagrams (Cont.)

State Machines

Behavioral State Machine

Examines behavior of one class

Protocol State Machine

Show dependencies of different interfaces of class

Use Case

Captures business requirements

Illustrates interaction between system and environment


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Use Case Diagram

Captures business requirements

Illustrates interaction between a system and its

environment

Includes end user

Any external system that interacts with its information

system

Documents and clarifies requirements of system being

modeled