SE203b: OO Design for Software Engineers. Office: TEB349, Ext

Transcription

1 SE203b: OO Design for Software Engineers W0 : Course Overview Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa Teaching Team Instructor TAs o Hamada Ghenniwa Office: TEB349, Ext hghenniwa@eng.uwo.ca o Abdul Masaud amasaud@engga.uwo.ca o Raafat Aburukba roaburuk@engga.uwo.ca Course URL Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 2

2 Class, Lab & Tut Lecture & Lab (TEB 244) o Wed. 2:30 5:30 pm. Lab#2 (TEB 244) o Mon. 9:30-11:30 Tutorial (TEB 244) o Thu. 11:30 12:30 Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 3 The Scope Design NOT Programming Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 4

3 Programming: Implementation class Staff_Member { // superclass of the employee hierarchy // Instance variables: basic info for any staff member protected String name; protected String address; protected String phone_number; // Constructor public Staff_Member (String emp_name, String emp_address, String emp_phone) { name = emp_name; address = emp_address; phone_number = emp_phone; public double pay() { // default pay method: will be overridden return 0.0; public void print() { // display basic info for any staff member System.out.println ("Name: " + name); System.out.println ("Address: " + address); System.out.println ("Phone: " + phone_number); // class Staff_Member Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 5 Programming: Implementation (Cont.) // Class Employee represents a paid staff member. class Employee extends Staff_Member { // Specific Employee data protected String social_security_number; protected double pay_rate; // Constructor public Employee (String emp_name, String emp_address, String emp_phone, String emp_ssnumber, double emp_rate) { super (emp_name, emp_address, emp_phone); social_security_number = emp_ssnumber; pay_rate = emp_rate; public double pay () { // overrides pay method from superclass return pay_rate; public void print () { // prints Employee data super.print(); // uses superclass print method System.out.println ("SS number: " + social_security_number); System.out.println ("Pay rate: " + pay_rate); // class Employee Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 6

4 Programming: Implementation (Cont.) // Class Volunteer represents an unpaid staff member. class Volunteer extends Staff_Member { // No additional instance variables // Constructor // invokes the superclass constructor to init basic info public Volunteer (String emp_name, String emp_address, String emp_phone) { super (emp_name, emp_address, emp_phone); // Overrides pay() method from the superclass public double pay() { return 0.0; // Explicitly returns 0 for a Volunteer // print method inherited from superclass // class Volunteer Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 7 A Challenge Change your application to handle different payments for Engineers, Executives and Hourly employees. Also we need to handle other aspects of the Firm where staff is one element. Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 8

5 Class Diagram: Design main() Firm Staff staff_list: Staff_Member [ ] payday() 1 * Staff_Member name: String address: String; phone_number: String pay() print() Employee social_security_number: String pay_rate: double pay() Volunteer pay() print() Engineers Executive bonus: double award_bonus() pay() print() Hourly hours_worked: int add_hours() pay() print() Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 9 What is the application? Software Requirements: A POS System A computerized NextGen point-of-sale (POS) system is to: record sales, and handle payments. It includes H/S components such as: Computer Bar code scanner Software It interfaces to various service applications, such as: Third party tax calculators Inventory control It must support multiple and varied client-side terminals and interfaces, such as: A thin Web browser terminal A regular PC with Java Swing graphical UI Touch screen input Wireless PDA s Furthermore, it should support different clients with different business rules. Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 10

6 Software Design Class Diagram Store address name addsale() Uses ProductCatalog getspecification() Contains ProductSpecification description price itemid Houses Looks-in Descri bes Register SalesLineItem endsale() enteritem() makenewsale() makepayement() Cpatures quantity getsubtotal() Contains Sale Logs-completed date iscomplete time becomecomplete() makelineitem() makepayement() Paid-by Payment amount Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 11 Implementation public class ProductCatalog { private Map productspecifications = new Hashtable(1000); public ProductCatalog() { //populating with sample data Integer id1 = new Integer(100); Integer id2 = new Integer(200); Money price = new Money( 3, "CAD"); ProductSpecification ps; ps = new ProductSpecification( id1, new Money(3,"CAD"), "product 1" ); productspecifications. put( id1, ps ); ps = new ProductSpecification( id2, new Money(5,"CAD"), "product 2" ); productspecifications.put( id2, ps ); public ProductSpecification getspecification( Integer id ) { return (ProductSpecification)productSpecifications.get( id ); public class ProductSpecification { private Integer id; private Money price; private String description; public ProductSpecification ( Integer id, Money price, String description ) { this.id = id; this.price = price; this.description = description; public Integer getitemid() { return id; public Money getprice() { return price; public String getdescription() { return description; Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 12

7 Object-Oriented Technologies Object Oriented Programming 1967: Simula by O.J. Dahl Class and Instance 1972: Parnas Module by D.Parnas Information hiding 1972: Smalltalk72 by Xerox PARC 1977: CLU by B. Liskov Abstract data type Object Oriented Analysis and Design 1986: OOD by G. Booch 1988: Shlare/Mellor, 1991: Coad/Yordon, 1991: OMT by J.Rumbaugh 1995: OOSE by Ivar Jacobson Now: UML by Booch, Rumbaugh and Jacobson 1981: Smalltalk80 by Xerox Class library 1986: Objective-C by Cox, C++ by Strusrup 1988: Eiffel by B. Meyer 1989: CLOS by Moon Now: Java Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 13 Learning Objectives Understand the role of design in Software Lifecycle Understand the main issues of software design Understand the important concepts of OO design Understand the importance and the role of software design metrics Learn basic design issues of specific application environments e.g., real-time and distributed systems Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 14

8 At the Concrete Level!! Design software systems using OO design language UML (Unified Modeling Language) Implement the design using OO programming language Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 15 The Road Map 1. Introduction to Software Design 2. Introduction to OO Paradigm 3. Software Design with OO Paradigm 4. Patterns in Design and Architecture 5. Selected Design Topics Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 16

9 Textbook Course notes and supplementary material UML Distilled: A Brief Guide to the Standard Object Modeling language; Martin Fowler, Addison-Wesley, 2004, ISBN Practical Object Oriented Design with UML; Mark Priestley, McGraw Hill, 2000, ISBN Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 17 References Software Engineering: A Practitioner's Approach, 6th Ed, Roger Pressman, McGraw-Hill, The Unified Modeling Language User Guide, Grady Booch, James Rumbaugh, and Ivar Jacobson, Addison-Wesley, Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 18

10 Evaluation Assignments 12% Labs 20% Pop Quizzes 5% Attendance 5% Project (2-P Team) 30% Final 30% Bonus & Participation +5% Jan. 11, 2006 SE203b, ECE UWO, Hamada Ghenniwa 19