ObjectOriented Software Development Software Development Life Cycle Software Development Process Mod

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Object-Oriented Software DevelopmentSoftware
Development Life CycleSoftware Development
Process ModelWeek 5Jarungjit Parnjai
Object Oriented Technology
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Software Development
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What Is Software?

• Software is
• ????????? (Instructions) ????????????????????????
  ????????????????????????????? ????????????????????
  ???????????? (computer programs)
• ??????????????? (Data structures)
  ??????????????????????????? ??????????????????????
  ???
• ?????? (Documents) ???????????????????????
  ???????????????????????

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How Does Software Work?

• ????????? (Instructions) ??? ?????? (data)
  ?????????????????????? ???????????????????????????
  ?????????????????
• ?????????????????????????????? ??????????
• ?????????? ??? Software ??????????????????

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Systems and Software Systems

• A System is
• An organized or connected group of Objects a
  whole composed of parts in orderly arrangement
  according to some scheme or plan

A software-intensive System (Software System) is
system ????????????????? software ????????
?????????? ???????????????????????????????????????
????????????????
Examples of Software Systems ????????????????,
???????????, ???????? ?????????????
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Why Do We Build Software Systems?

• ?????????????????????????????? customer
• software ??????????????????????????????
• software ????????????????????????????????????????
  ??????

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How Do We Build Software Systems?

• ???????????? decomposition ??? synthesis
• ????????? ???????????????????????????????????????
  ???????????????????????????? (??????????
  Specification/Analysis)
• ??????/??????????????????????????????? (problem
  domain) ?????????????????????????
• ??????????????? (Synthesize) ?????????????????
  (solution) ?????????????? actions ???? data
  (?????????? Design /Implementation)

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Software Development Methodology
Notation
Process
Tools
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Software Development Phases

• Requirement Specification define problem domain
• Analysis what problem to be solved?
• Design how to solve the problem?
• Implementation how to implement the solution?
• Testing how to ensure that the solution can
  solve the problem?
• Maintenance how to adjust the solution to
  accomodate change?
• Retirement when does the system to be retired?

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Software Development Life Cycle Model

• SDLC Model
• ???????????????????????????? ????????????????
  Software (Software Development Process)
• ????????????????????? ???????????????
• ?????? Model ????????????????????????????????????
  ?? ???? Waterfall Model, Incremental Model,
  Spiral Model ???????
• ????? Software ??? Model ???????????????????????
• ????? Model ????????? ??????? ????????

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Build-and-Fix Model
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Waterfall Model
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Rapid Prototyping Model
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Spiral Model
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Incremental Model
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And more...

• Spiral Model
• ...

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The Cost of Change
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What Techniques Can Be Used?

• ?????????????????? software engineer
  ????????????????????????????(Synthesis)
  ?????????????????
• ???????? Process (Action)
• ???????? Data
• ???????? Object

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Traditional Software Development

• ??? Structured Analysis Design Techniques
• ???????????? Data (Data-Oriented)
• ???????????? Data Flow Model, ER
  (Entity-Relational) Model
• ???????????? Action (Action-Oriented)
  ???????????????/???????? Data
• ???????????? Finite State Machine (FSM)
• ??? Structural/Procedural Implementation
  Techniques
• ??? Structured/Procedural Programming Languages
• ???????????? BASIC, Pascal, C

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Problems with Traditional Techniques

• Do Traditional techniques work?
• Yes, they do (at a cost !!!)
• Problems
• ?????????? Commercial Software ???????? ????????
  Traditional Techniques
• Software ?????????? ?????????????????
  ??????????????????????????????????????????????????
  Hardware
• ????????????????????? Software Design ???
  Implementation ?????????? ????????????????????
• ????????????? Software ?????????????
  ???????????????????????????????

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Software Crisis

• Software ???????????????? (Change) ????????
• ???? Software ???? (Legacy Software)
  ????????????????????????????????????????????????
  (Interoperability)
• ?????????????????????????? Software ????
  (Extendability)
• ??????????? Software ?????????????????????????
  (Reusuability)
• ???????? Software ??????????? ????????????????????
  ??????????

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Software Crisis

• ???????? Hardware ???????
• ???? (Size) ?????????? ????????
  ??????????????????? (Complexibility) ???????
• ??????????? Software ??? ????? bug
• ?????????? (Cost) ?????????? ????????????????
  (Maintainability)
• ????????????????? (Time to Market) ??? ????
  ??????????????????????????????????????????????????
  ????
• ??????????????? Users ??? Programmers

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What are Object-Oriented Techniques?

• ????????????? Software Decomposition
• ????????????? (attribute/data) ???
  ???????/???????? (Action/behavior)
  ??????????????? (Object)
• ??????????????????? Synthesis
• ?????????????????????????? ???????????????
  ?????????????? Data ??? Actions
  ?????????????????????????? Object
• ?????????? Data ??? Actions ???????????????????
  ???????? ??????????? Module
• ????????????????????? (Problem Domain)
  ??????????????????????????? (Modeling Objects)
  ??????????????????? (Real World)

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What are Object-Oriented Techniques?

• ??????? software ??????????? clients ??? servers
• servers ???? Implementation ??? Actions ?????????
  Interface
• clients ???????????????? Interface ??? server
  ?????????????????????

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Object-Oriented Software

• ?????????????????? (Object-Oriented Software)
• ??? ????? ???????(Collection) ???????????????????
  ????????????????????????????????????
  ????????????????????????????? ?????????????
  (Message) ???????????????

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What is Software Modeling?

• ???????????????? (Modeling)
• ???????????????????? ????????? (Analysis and
  Design) ???????????????????????????????????
  ????????????????????????????????
• ????????????????????????????? ????????????????????
  ?????????????
• Visual Modeling
• ????????????????????????????????????

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Software Modeling
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Models

• Requirement Analysis Models (Requirement
  Specification)
• ??????????????????????????????????????????????
  ?? (Requirement Analysis)
• Analysis Model
• ?????????????????????????????????????????????
  ? (System Analysis)
• Design Model
• ???????????????????????????????????? (System
  Design)

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From Analysis to Design

• Analysis Phase
• ???????? ???????????????????????????
  ?????????????????? ?????? ??? ?????????????
  ??????????????????????
• ???? what happens in the current system? ???
  what is required in the new system?
• ????? Analysis Model ???????????????????????????
  ?????? ?????????????????????????????????????????
• Use Case Diagram / Requirement
• Analysis Model Class Diagram

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From Analysis to Design

• Design Phase
• ???????? Solution ?????????? Requirement
  ?????????? Analysis Phase
• how the system will be constructed without
  actually building it?
• Phase ??????? Software Development Life Cycle
• water fall clear cut ??????? analysis ???
  design
• iterative ????? clear cut ??????? analysis ???
  design

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Traditional SDLC

• ??????????????????????????? ?? Advantage ???
  Clear Cut ??????? Analysis ??? Design ??????
• project management
• Staff Skill and experience
• Client Decision
• choice of development environment
• ?????????????????? Analysis ??? Design
  ??????????? ????????? Diagram ??????
• Analysis ??? Data Flow Diagram
• Design ??? Structure Diagram/ Structure Charts

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Object-Oriented Approached

• ?????? Model ??????????????????????????????????
  (Software Development Life Cycle)
• ?????????????????? Analysis ??? Design
  ??????????? ????????????????????????????? Model
  Rumbaugh 1997
• ????? Design Model
• Interaction Diagrams
• State Diagrams
• Design Model Class Diagrams

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System and Detailed Design

• ???????????????????????? 2 ?????
• System Design ???????????????????????????????????
  ?????? ??????????? standards
• ???????? standards ???? ????????? human-computer
  interface
• Detailed Design ??????????????????????????????????
  ????????? ????????????????????????????????????
  ??? ?????????? standard ????????????
• ???? ????????? Object

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System Design

• ??????????????????????????????????? ????
• ?????????????????????????? ?????? ????
  Client-Server
• ??????????????? how processes and objects will
  be distributed to different machine?
• System Architect/System Design ?????????????????
  ??????????? ?????????????????????????
• ????????? Standards ?????????? ????
• ???????????????? Standards ????????? Use
  Interface ???????????????? Interface ????????
  system

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Detailed Design

• Detailed design ??? Traditional System/Structured
  System ??????????????????????????? activities
  ????? ??????
• ????????? Inputs
• ????????? Outputs
• ????????? Processes
• ????????? files
• Detailed design ??? OO System ????????????????????
  ???? activities ????? ?????????????
  ????????????????????????
• reusability
• ???????? responsibilities ?????? ????

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Reuse

• ??????????????????????? (Design Reuse)
  ?????????????? 2 levels ??????
• ?????? design patterns
• ???????????????? Analysis Phase
  ???????????????????????????????
  ?????????????????? ???? ????? ????????????????????
  ?? ????????????????? ????????????? ???? ???????
  vendor ?????? (Components)

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Assignment of Responsibilities to Classes

• ???????? Responsibilities ??????????
• ??????? main task ????????????
• ?????????????????
• ???????? responsibilities ?????? Operation
  ????????????????????

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Criteria for Good Design

• Low Coupling
• High Cohesion

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Summary

• Software, Systems and Software Systems
• Software Crisis
• Software Development Process Model
• Traditional Software Development
• Object-Oriented Software Development