tutorial

Danielsj

Description

OOPSLA 2000Component-Based Design:A Complete Worked ExampleJohn DanielsSyntropy Ltd, UK' John Daniels 2000 [e-mail]• Goal: follow a small example from requirementsthrough to code-ready specification• Component-based: assume that the targettechnology will be COM+, EJB or similar• Process-centric: follow a well-defined design process• Specification-oriented: most of the tutorial will beconcerned with specifying the system and itscomponents• UML: use standard UML to describe thespecificationsJohn Daniels - Component-based Design1Tutorial Map• Introduction• Design Process• Requirements Definition• Component IdentificationBreak• Component Interaction• Component Specification• ProvisioningBlueprint for the systems beingconsidered in this tutorialActive/JavaServerHTTPPageDCOM / IIOP / RMIComponentObjectComponent ExistingObject SystemComponentObjectSQL, etc.ComponentDatabaseObjectComponentObjectCOM+ / EJBJohn Daniels - Component-based Design2System architecture layersUser InterfaceCreates what the user sees.Handles UI logic.User DialogDialog Logic: corresponds to use cases.Transient state corresponds to the dialog. client partCan sometimes be used with multiple UIs.Business System server partOperations are new transactions.Can be used with a variety of user dialogs or batch.Components correspond to Business Systems .No dialog or client related state.Business Services/EntitiesComponents ...

Informations

• Publié par: Armyo
• Nombre de lectures: 18
• Langue: English

Extrait

OOPSLA 2000

Component-Based Design: A Complete Worked Example

© John Daniels 2000

John Daniels Syntropy Ltd, UK

Introduction

[e-mail]

 Goal: follow a small example from requirements through to code-ready specification  Component-based: assume that the target technology will be COM+, EJB or similar  Process-centric: follow a well-defined design process  Specification-oriented: most of the tutorial will be concerned with specifying the system and its components  UML: use standard UML to describe the specifications

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Tutorial Map

 Introduction  Design Process  Requirements Definition  Component Identification  Component Interaction  Component Specification  Provisioning

Break

Blueprint for the systems being considered in this tutorial

Active/Java HTTP Server Page

DCOM / IIOP / RMI

Component Object Component Existing Object System Component Object Component SQL, etc. Databa Object se Component Object COM+ / EJB

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System architecture layers

User Interface Creates what the user sees. Handles UI logic. User Dialog Dialog Logic: corresponds to use cases. Transient state corresponds to the dialog. Can sometimes be used with multiple UIs. Business System Operations are new transactions. Can be used with a variety of user dialogs or batch. Components correspond to Business Systems .  No dialog or client related state. Business Services/Entities Components correspond to stable business types or groups. Operations can be combined with others in a transaction. Usually have associated databases.

The Design Process

Informal, organic, design process

Formal, cyclic, evolutionary, management process

client part server part

 The design process is organised around the production of artefacts  The management process is organised around the delivery of working software

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Workflows in the design process Business requirements Existing Artefact assets Requirements

Busine m s o s d  C el o s ncept Technical s Components int U er s f e a r ce constraint Use Case ecification Provision models  AssemblySp ing C & o   mpo h n i e t n e t c   t s u p r e e c s s Assemblies arc Test Tested assemblies Deployment

Workflow (c.f. RUP)

The scope of this tutorial

Requirements S ification pec Component Identification

Provisioning

Component Interaction

Component Specification

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Organising the artefacts in tool packages

Use Case Diagram

Class Diagram

Requirements Business Concept Model Use Case Model Specification Business Type Model Interface Specifications Component Specifications Component Architecture

UML diagrams Business Concept Model Requirements Diagram Use Case Diagrams Business  Concept Model Use Case Model Business Specification Type Model Interface Diagram Specification Diagrams B In u t si e n r e f s a s c   e T  S yp p e e   ci M f o ic d a e t l i Re I s nterface ons ponsibility Component Diagram Sp D e i c a i g fi r c a a m ti s on Component Specifications Component Architecture Component Architec a t m ure Interactions I C n D o t i m e a p r g o a ra n ct e m i n s o t n Diagr Package Diagram

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Class Diagram

Collaboration  Diagram

Evolutionary delivery

 All the artefacts evolve at each iteration  Focus is on delivery to the user

0%

% complete

Concept model Use Case model Component specs Components 1st iteration 2nd iter. 3rd iter. 4th iter.

Requirements Definition

Problem domain Business knowledge requirements Requirements Definition Develop Business Develop business Concept Model processes Identify Use Cases

ness U C B o u n si cept se Cases Model

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100%

5th iter.

Software boundary decisions

Business process

We want to provide some automated support for managing hotel reservations io kaTpu e esertavr n

customer arrives/ Wait for enquiry/ [else]  event  cancel request/ Check amendment Cancel availability [suitable  request/ reservation room] Make Amend no show/ reservation reservation

Confirm reservation

Process no Notify billing show system

Business Concept Model Hotel Chain 1 1 .*  1..* Clerk . Hotel 1 * contactedHotel 1  1 * * 1..* Customer 1 * onRsereavit locaal *01.. itno Room 1 1  *  * contactAddress 0..1  1 Address 1 RoomType 0..1 1 Bill

Payment 0..1

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Assign responsibilities

Guest enquiry/ [else] Check availability [suitable room] ReservationMake maker reservation System

Confirm reservation

Take up reservation

customer arrives/ Wait for event cancel request/ amendment request/ Cancel reservation Amend no show/ reservation

Process no Notify billing show system

Identify Use Cases A use case describes the interaction that follows from a single business event. Where an event triggers a number of process steps, all the steps form a single use case. Take up reservation Guest customer arrives/ Wait for enquiry/ [else]  event  cancel request/ Check amendment availability request/  Cancel   [suitable reservation room] Reservation  no show/Make Amend maker reservation reservation System

re C s o e n r f v i a r t m ion Pro s c h e o s w s noNotify billing system

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ReservationMaker

Guest

BillingSystem

ReservationAdministrator

Reservation system Cancel a reservation Make a reservation Update a reservation Take up a reservation Process no shows Add, amend, remove hotel, room, customer, etc.

Use Case diagram

Name Make a Reservation Initiator Reservation Maker Goal Reserve a room at a hotel Steps Main success scenario or 1. Reservation Maker asks to make a reservation Extension 2. Reservation Maker selects hotel, dates and room type Points 3. System provides availability and price 4. Reservation Maker agrees to proceed 5. Reservation Maker provides name and postcode 6. Reservation Maker provides contact email address 7. System makes reservation and gives it a tag 8. System reveals tag to Reservation Maker 9. System creates and sends confirmation by email Alternatives Extensions Use an informal 3. Room Not Available Alternatives  a) System offers alternative dates and room types section if you dont  Reservation Maker selects from alterna b) want to specify the  tives detail required for an extension 6. Customer already on file  a) Resume 7

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

Exercise 1

Complete the use case on the next slide

Name Take up a Reservation Initiator Guest Goal Claim a reservation

Main success scenario 1. Guest arrives at hotel to claim a room 2. Guest provides reservation tag to system 3.

Extensions

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Component Identification

Business Concept Use Case Model Model Component Develop Business ionicatntifIed Type Model Existing Interfaces Identify  Business Identify System Interfaces Interfaces & Ops Existing Architecture Assets Create  Initial  Patterns Comp Specs & Architecture Business Component System Interfaces Specs & Interfaces Architecture

Business Type Model

 om * natio Ctnenopmo ificepS C po e n fi e i n t t i   o I n n   t o e f rf a a s c e e t of 1 * ortedInterfaceppus c  A d n .. behaviours that can be offered Component 1 by a Component Object Interface * erlaization  Component Specification  The specification of a unit of Component software that describes the Implementation behaviour of a set of objects, and defines a unit of 1 implementation and deployment Component * innsitoaaltl  Co  m S  A p r o e n al i e iz cif n a t ti I o m n p o l f e a m C e o nt m a p ti o o n n ent concepts Insed Co tall netpmno  Install p e e d c Co ati m o p n onent  An installed (or deployed) copy 1 of a Component Implementation * instance  Object Component  An instance of an Installed Component Component. A run-time concept Object

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