Jerry KotubaSYST39409-Object Oriented Methodologies1 Object Oriented Methodologies Week04

Jerry KotubaSYST39409-Object Oriented Methodologies2 Agenda Schedule Review Solution for ICE-02 Notation (start/end) Orthogonal Lines File type pdf or docx only Recap last class Use Cases Discovery Narratives Activity Diagrams Packages Class Diagrams

Jerry KotubaSYST39409-Object Oriented Methodologies3 Events and Use Cases Use case Activity the system carries out Entry point into the modeling process Discovery Techniques Event decomposition User goal CRUD Elementary business processes (EBPs) Basic unit of analysis Initiated by event occurring at specific time and place Discrete system response that adds business value

Use Cases - Analysis Identify User goals Event tables CRUD Summarize Use Case Diagram Describe Narratives Activity Diagram(workflow) Jerry KotubaSYST39409-Object Oriented Methodologies4

Final Word on Use Cases Large software projects usually organized into packages. Package is a placeholder Each package contains a set of use cases for handling a certain type of business activity. E.g. Supply Chain Management System  Warehouse & Shipping  Order Processing  Accounting  Inventory Management Jerry KotubaSYST39409-Object Oriented Methodologies5

Methods & Applications6 Customers Suppliers

Methods & Applications7 E-business Supply Chain Management E-commerce Customer Relationship Management Legacy Applications New Applications Packaged Application External Services 3 rd Party Inter- Intra Company

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Jerry KotubaSYST39409-Object Oriented Methodologies9 Example without Package Notation

Jerry KotubaSYST39409-Object Oriented Methodologies10 Example using Package Notation

Jerry KotubaSYST39409-Object Oriented Methodologies11 Class Diagrams- Objectives Identify and analyze the objects and object-classes needed in a system Learn how to identify and represent relationships between object classes. Learn how to identify and create super/subclass relationships

Jerry KotubaSYST39409-Object Oriented Methodologies12 Problem Domain Classes Problem domain Abstraction  ”Real World” to “Data world” Set of work-related “things” in system component Things have data representation within system Examples: products, orders, invoices, customers OO approach to things in problem domain Objects that interact in the system Identify and understand things in problem domain Key initial steps in defining requirements

Jerry KotubaSYST39409-Object Oriented Methodologies13 Types of Things Things can be identified with methodology Separate the tangible from the intangible Include information from all types of users Ask important questions about nature of event “What actions upon things should be acknowledged and recorded by the system?”

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Jerry KotubaSYST39409-Object Oriented Methodologies15 Procedure for Developing an Initial List of Things Perform Textual Analysis List nouns users mention when discussing system Event table as source of potential things Use cases, external agents, triggers, response Select nouns with questions concerning relevance Further research may be needed

Jerry KotubaSYST39409-Object Oriented Methodologies16 Pharmacy System Example

Jerry KotubaSYST39409-Object Oriented Methodologies17 Associations among Things Analyst document entity associations ( relationships) Example: “Is placed by” and “works in” Associations apply in two directions Customer places an order An order is placed by a customer Multiplicity: the number of associations One to one or one to many The associations between types of things Unary (recursive), binary, n-ary

Jerry KotubaSYST39409-Object Oriented Methodologies18 Associations Naturally Occur between Things

Jerry KotubaSYST39409-Object Oriented Methodologies19 Multiplicity of Relationships

Jerry KotubaSYST39409-Object Oriented Methodologies20 Attributes of Things Specific details of things are called attributes Analyst should identify attributes of things Identifier (key): attribute uniquely identifying thing Examples: Social Security number, vehicle ID number, or product ID number Compound attribute is a set of related attributes Example: multiple names for the same customer

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Jerry KotubaSYST39409-Object Oriented Methodologies22 Classes and Objects Domain model class diagram as UML class OOA applies domain model class diagram to things Problem domain objects have attributes Software objects encapsulate attributes and behaviors Behavior: action that the object processes itself Software objects communicate with messages Information system is a set of interacting objects

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Exercises No 1 to No 3 To be done in class for illustration and practice Jerry KotubaSYST39409-Object Oriented Methodologies26

Jerry KotubaSYST39409-Object Oriented Methodologies27 Your Turn…ICE-03 See SLATE

Class Diagrams Document the static structure of the system They define what classes there are and how they are related The symbol on the right defines the data and behaviour encapsulated by a class. Objects “know things and know how to do things!” Jerry Kotuba 28 SYST Object Oriented Methodologies