COMPSCI 172 – Introduction to Objected-Oriented programming in Java

1. COMPSCI 172– Introduction to Objected-Oriented programming in Java Class hour: 12:05-12:55 pm MWF (section 1). 1:10-2:00 pm MWF (section 2) McGraw Room 115

2. Course Objectives • Given a description of a simple problem, formulate algorithms following object-oriented design concepts to solve this problem • Given a description of a simple problem, implement the solution in Java which uses class construction, interface, methods, messages passing, file processing, and simple Graphical User Interface

3. Textbook/Technology requirement Textbook: An Introduction to Object-Oriented Programming with Java (third edition). C. Thomas Wu. 2004. McGraw-Hill Publishing Software: • J2SE Software Development Kit (SDK): http://java.sun.com/j2se/1.4.2/download.html • Textpad: download at http://www.textpad.com/download/index.html#downloads

4. Introduction Tell me about yourself and what you expect to get out from this course

5. Self-Introduction • Recently graduated from the University of Connecticut (05 Class), Ph.D in Computer Science and Engineering • Master of Computer Science from UW-Milwaukee (96-99) • Bachelor of Science from Hanoi University of Technology (86-91)

6. Self-Introduction • Research Experience: • User Modeling, Information Retrieval, Decision Theory, Collaborative Filtering, Human Factors • Teaching Experience: • CS172, 181, 271 at UWW • Introduction courses at UOP and Devry • TA for Computer Architecture, OO Design, Compiler, Artificial Intelligence

7. Self-Introduction • Teaching philosophy: • Interactive • Adaptive • Pro-active • Collaborative • Other hobbies (non-academic related) • Movies • College Basketball • Family activities

8. Contact information nguyenh@uww.edu Baker Hall 324 Office Hours: 2:15-4:15pm, MWF, or by appointment 262 472 5170

9. Course detail - Topics Object-oriented design and implement using Java Understanding of algorithm, objects, classes Fundamentals of Java language & program Specific Applications

10. Course detail - Evaluation

11. What does it take to success • Practice, practice, practice!!! (Programming, reading, doing practice exercises) • Prior programming skills help • Participate in class discussion and group discussion • Thinking, thinking, thinking!!!

12. Questions?

13. Introduction to OO Programming and Java

14. Lesson plan • History & Novelty of Java • Class & Objects

15. History • High-level programming language • Low level programming language: CPU instruction sets. • High level programming languages: • Compiled (C/C++, Pascal) and interpreted language (Basic) • Procedural (Pascal, C) and object oriented language (C++, Java)

16. Java’s Ancestry • Oak: a reimplementation of C++ in the early 1990s by James Gosling. • Intended for intelligent consumer devices. • Oak became Java in 1995. • Portability and Security of primary concern. • Eminently suitable for Web applets. • Also a powerful language in its own right.

17. What is news with Java? • Platform-independent (portability) • The JVM is an imaginary CPU with bytecode instructions. Java programs are translated to bytecodes by the Java compiler • Object-oriented: code reusable • Lost of resources and tools

18. What is news with Java • Inheritance: • capability of a class to use the properties and methods of another class while adding its own functionality • Polymorphism: • capability of an action or method to do different things based on the object that it is acting upon

19. Practice (LoanCalculator) • Type in TextPad and save the file as LoanCalculator.java • Compile in TextPad by: • Tool -> Compile Java • Run this application by • Tool -> Run Java Application (First save LoanCalculator.java file to C:\Document and Setting, under your directory, compile and run it)

20. /** * Sample program … **/ import javax.swing.*; /* Multiple comments */ import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Multi-line comment Comments Single-line comment

21. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { /* Add a multi-line comment here */ final int MONTHS_IN_YEAR = 12; // Add your comment here double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00");

22. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Import statement

23. /** * Sample program … **/ // import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00");

24. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Class Declaration

25. /** * Sample program … **/ import javax.swing.*; import java.text.*; Public class loancalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00");

26. /** * Sample program … **/ import javax.swing.*; import java.text.*; class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Class Declaration

27. Class and Objects • A class definition provides a description of a typical object within that class. • student, faculty, person • An individual object is an instance of a class. • Definition of behavior (methods) and attributes (fields).

28. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Behaviors (Main Method)

29. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ private final int MONTHS_IN_YEAR = 12; public static void main(String[] args) { double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Attributes (Fields)

30. Class and Objects (Example) Student Name ID Credit earned Class Student_Steven Name=“Steven” Id=“001” Credit earned=50 Student_Emily Name=“Emily” Id=“002” Credit earned=100 Objects

31. Class and Instances • Class definition is like a blueprint or template. • Color, size, pattern might vary, but instances of the same class come from the same mold .

32. Object Interactions • Communication between people: • Information: “I am going to a party.” • Question: “What is the time?” • Order/Request: “Please buy me some gum.” • Objects communicate in similar ways. getStudentEarnedCredits() Professor A StudentSteven 50

33. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df = new DecimalFormat("0.00"); Object Instantiation

34. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan ….. DecimalFormat df; // ….

35. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan String inputStr; ….. inputStr = JOptionPane.showInputDialog(null,"Loan Amount (dollars.cents):"); Object Interactions

36. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; double loanAmount; // represents the amount being borrowed int loanPeriod; // represents the number of years of the loan String inputStr; ….. inputStr = JOptionPane.showInputDialog(null,"Loan Amount (dollars.cents):"); Variable Declaration

37. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { final int MONTHS_IN_YEAR = 12; // double loanAmount; // represents the amount being .. int loanPeriod; // represents the number of years of the loan String inputStr; ….. inputStr = JOptionPane.showInputDialog(null,"Loan Amount (dollars.cents):");

38. /** * Sample program … **/ import javax.swing.*; import java.text.*; public class LoanCalculator{ public static void main(String[] args) { monthlyInterestRate = annualInterestRate / MONTHS_IN_YEAR/ 100; numberOfPayments = loanPeriod * MONTHS_IN_YEAR; monthlyPayment = (loanAmount * monthlyInterestRate)/(1- Math.pow(1/(1+monthlyInterestRate),numberOfPayments)); totalPayment = monthlyPayment * numberOfPayments; Assign Statement Expressions

39. Inheritance Student Graduate student Undergraduate student Masters Doctoral Law/ Medicine Commuting Resident

40. Questions?