OOP Part 2. Introduction to OOP with Java. Lecture 08: Introduction to OOP with Java - AKF Sep AbuKhleiF -
|
|
- Hilary Sims
- 6 years ago
- Views:
Transcription
1 Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 08: OOP Part 2 Instructor: AbuKhleif, Mohammad Noor Sep 2017 AbuKhleiF - 1
2 Instructor AbuKhleif, Mohammad Noor Computer Engineer (JU ) Software Automation Atypon John Wiley and Sons Company - Jordan Branch Reach me at: moh.noor94@gmail.com facebook.com/moh.noor94 twitter.com/moh_noor94 3 Course Java SE Basics Object Oriented Programming Course Page: /courses/java-101-sep-2017 Or, go to: Courses Java 101 Course Sep 2017 Course Facebook Group: 4 AbuKhleiF - 2
3 Static Variables, Constants, and Methods 5 Static Variables, Constants, and Methods All variables declared in the data fields of the previous examples are called instance variables. An instance variable is tied to a specific instance of the class. It is not shared among objects of the same class. It has independent memory storage for each instance. 6 AbuKhleiF - 3
4 Static Variables, Constants, and Methods In the following example, the radius of the first object circle1 is independent of the radius of the second object circle2 : Circle circle1 = new Circle(); Circle circle2 = new Circle(5); 7 Static Variables, Constants, and Methods Static variables, also known as class variables, store values for the variables in a common memory location. A static variable is used when it is wanted that all instances of the class to share data. If one instance of the class changes the value of a static variables, all instances of the same class are affected. Static methods can be called without creating an instance of the class. 8 AbuKhleiF - 4
5 Static Variables, Constants, and Methods To declare a static variable or define a static method, put the modifier static in the variable or method declaration. Since constants in a class are shared by all objects of the class, they should be declared static. final static double PI = ; Static variables and methods can be accessed from a reference variable or from their class name. 9 Welcome to Java Program - Revisit // This program prints Welcome to Java! public class Welcome { public static void main(string[] args) { System.out.println("Welcome to Java!"); 10 AbuKhleiF - 5
6 public class CircleWithStaticMembers { /** The radius of the circle */ double radius; final static double PI = ; /** The number of the objects created */ static int numberofobjects = 0; /** Construct a circle with radius 1 */ CircleWithStaticMembers() { radius = 1.0; numberofobjects++; /** Construct a circle with a specified radius */ CircleWithStaticMembers(double newradius) { radius = newradius; numberofobjects++; Example /** Return numberofobjects */ static int getnumberofobjects() { return numberofobjects; /** Return the area of this circle */ double getarea() { return radius * radius * PI; 11 public class TestCircleWithStaticMembers { /** Main method */ public static void main(string[] args) { System.out.println("Before creating objects"); System.out.println("The number of Circle objects is " + CircleWithStaticMembers.numberOfObjects); // Create c1 CircleWithStaticMembers c1 = new CircleWithStaticMembers(); // Display c1 BEFORE c2 is created System.out.println("\nAfter creating c1"); System.out.println("c1: radius (" + c1.radius + ") and number of Circle objects (" + c1.numberofobjects + ")"); // Create c2 CircleWithStaticMembers c2 = new CircleWithStaticMembers(5); // Modify c1 c1.radius = 9; Example // Display c1 and c2 AFTER c2 was created System.out.println("\nAfter creating c2 and modifying c1"); System.out.println("c1: radius (" + c1.radius + ") and number of Circle objects (" + c1.numberofobjects + ")"); System.out.println("c2: radius (" + c2.radius + ") and number of Circle objects (" + c2.numberofobjects + ")"); 12 AbuKhleiF - 6
7 Example 13 UML Class Diagram: Static Members Example Circle radius: double numberofobjects: int getnumberofobjects(): int getarea(): double instantiate instantiate circle1 radius = 1 numberofobjects = 2 circle2 radius = 5 numberofobjects = 2 Memory 1 radius 2 5 radius numberofobjects After two Circle objects were created, numberofobjects is 2. Static members are underlined in UML class diagrams. 14 AbuKhleiF - 7
8 Relationship between Static and Instance Members An instance method can invoke and access static and instance members. A static method can only invoke and access static members. 15 Instance or Static? How to decide whether a variable or method should be an instance one or a static one? A variable or method that is dependent on a specific instance of the class should be an instance variable or method. Example: radius and getarea of the Circle class; each circle has its own radius and area. A variable or method that is not dependent on a specific instance of the class should be a static variable or method. Example: numberofobjects of the Circle class; all circles should share this value. 16 AbuKhleiF - 8
9 Let s Code Build a class that can count the number of instances of itself. Make 3 objects of this class and print the number of instances before and after each one. 17 Visibility Modifiers 18 AbuKhleiF - 9
10 Visibility Modifiers Visibility modifiers can be used to specify the visibility of a class and its members. A visibility modifier specifies how data fields and methods in a class can be accessed from outside the class. There is no restriction on accessing data fields and methods from inside the class. 19 Visibility Modifiers If no visibility modifier is used, then by default the classes, methods, and data fields are accessible by any class in the same package. This is known as package-private or package-access. 20 AbuKhleiF - 10
11 Packages Packages are used to organize classes. To do so, you need to add the following statement as the first statement in the program: package packagename; If a class is defined without the package statement, it is said to be placed in the default package. 21 Visibility Modifiers The public modifier can be used for classes, methods and data fields to denote that they can be accessed from any other classes. The private modifier makes methods and data fields accessible only from within its own class 22 AbuKhleiF - 11
12 Welcome to Java Program - Revisit // This program prints Welcome to Java! public class Welcome { public static void main(string[] args) { System.out.println("Welcome to Java!"); 23 Visibility Modifiers: Methods and Data Fields Example package p1; package p2; public class C1 { public int x; int y; private int z; public void m1() { void m2() { private void m3() { public class C2 { void amethod() { C1 o = new C1(); can access o.x; can access o.y; cannot access o.z; can invoke o.m1(); can invoke o.m2(); cannot invoke o.m3(); public class C3 { void amethod() { C1 o = new C1(); can access o.x; cannot access o.y; cannot access o.z; can invoke o.m1(); cannot invoke o.m2(); cannot invoke o.m3(); 24 AbuKhleiF - 12
13 Visibility Modifiers: Classes Example package p1; package p2; class C1 {... public class C2 { can access C1 public class C3 { cannot access C1; can access C2; 25 Visibility Modifiers: Note An object cannot access its private members, as shown in (b). It is OK, however, if the object is declared in its own class, as shown in (a). public class F { private boolean x; public static void main(string[] args) { F f = new F (); System.out.println(f.x); System.out.println(f.convert()); private int convert(boolean b) { return x? 1 : -1; (a) This is OK because object f is used inside the F class public class Test { public static void main(string[] args) { Foo f = new F(); System.out.println(f.x); System.out.println(f.convert(f.x)); (b) This is wrong because x and convert are private in F. 26 AbuKhleiF - 13
14 Visibility Modifiers: Conclusion The private modifier restricts access to within a class. The default modifier restricts access to within a package. The public modifier enables unrestricted access. The protected modifier (later). 27 UML Class Diagrams (2) 28 AbuKhleiF - 14
15 UML Class Diagrams Circle -radius: double -numberofobjects: int +Circle() +Circle(radius: double) +getradius(): double +setradius(radius: double): void +getnumberofobject(): int +getarea(): double The radius of this circle (default: 1.0). The number of circle objects created. Constructs a default circle object. Constructs a circle object with the specified radius. Returns the radius of this circle. Sets a new radius for this circle. Returns the number of circle objects created. Returns the area of this circle. The (-) sign indicates a private modifier. The (+) sign indicates a public modifier. 29 Data Field Encapsulation 30 AbuKhleiF - 15
16 Data Field Encapsulation It is not a good practice to allow data fields to be directly modified. Data may be tampered with. The class becomes difficult to maintain and vulnerable to bugs. To prevent direct modifications of data fields, you should declare the data fields private. This is known as data field encapsulation. 31 Data Field Encapsulation A private data field cannot be accessed by an object from outside the class that defines the private field. However, a client often needs to retrieve and modify a data field. To make a private data field accessible: Provide a get method to return its value. Provide a set method set a new value to it. 32 AbuKhleiF - 16
17 Data Field Encapsulation A get method has the following signature: public returntype getpropertyname() If the returntype is boolean, the get method is defined as follows by convention: public boolean isproperyname() A set method has the following signature: public void setpropertyname(datatype propertyvalue) 33 IntelliJ IDEA Shortcuts Alt + Insert 34 AbuKhleiF - 17
18 public class CircleWithPrivateDataFields { /** The radius of the circle */ private double radius = 1; /** The number of the objects created */ private static int numberofobjects = 0; /** Construct a circle with radius 1 */ public CircleWithPrivateDataFields() { numberofobjects++; /** Construct a circle with a specified radius */ public CircleWithPrivateDataFields(double newradius) { radius = newradius; numberofobjects++; Example 35 /** Return radius */ public double getradius() { return radius; /** Set a new radius */ public void setradius(double newradius) { radius = (newradius >= 0)? newradius : 0; /** Return numberofobjects */ public static int getnumberofobjects() { return numberofobjects; /** Return the area of this circle */ public double getarea() { return radius * radius * Math.PI; These two methods are the only way to access the radius. This method is the only way to read the numberofobjects. numberofobjectsis only modified when a new object is created, there is no other way to modify it. Example 36 AbuKhleiF - 18
19 public class TestCircleWithPrivateDataFields { /** Main method */ public static void main(string[] args) { // Create a Circle with radius 5.0 CircleWithPrivateDataFields mycircle = new CircleWithPrivateDataFields(5.0); System.out.println("The area of the circle of radius " + mycircle.getradius() + " is " + mycircle.getarea()); // Increase mycircle's radius by 10% mycircle.setradius(mycircle.getradius() * 1.1); System.out.println("The area of the circle of radius " + mycircle.getradius() + " is " + mycircle.getarea()); Example 37 Let s Code Create a class called Date that includes three pieces of information as instance variables: A month (int), a day (int) and a year (int). Your class should have a constructor that initializes the three instance variables and assumes that the values provided are correct. Provide a set and a get method for each instance variable. Provide a method displaydate that displays the month, day and year separated by forward slashes (/). Write a test application named DateTest that demonstrates classdate s capabilities. 38 AbuKhleiF - 19
20 Let s Code Create a class called Employee that includes three pieces of information as instance variables: A first name (String), a last name (String) and a monthly salary (double). Your class should have a constructor that initializes the three instance variables. If the monthly salary is not positive, set it to 0.0. Provide a set and a get method for each instance variable. Write a test application named EmployeeTest that demonstrates class Employee s capabilities. Create two Employee objects and display each object s yearly salary. Then give each Employee a 10% raise and display each Employee s yearly salary again. 39 Homework AbuKhleiF - 20
21 Homework Part 1: Build a class called Utility that has methods to analyze a String parameter: One method can get you the number of occurrences of the and a in a String, Another one that finds if a String is a Palindrome, Another one that finds if a number is Armstrong. 41 Homework Part 2: Write a test application named UtilityTest that demonstrates class Utility capabilities. 42 AbuKhleiF - 21
22 Homework Submission Submit only the Utility.java file. Upload your file to the Facebook group. Submission due: Thursday, Sep 28-08:00 PM Late submission will not be reviewed by the instructor. Public solutions upload goal is to share knowledge, you can see other s solutions, but, please, don t cheat yourself! Don t forget, your solution should be well-documented, welldesigned, and well-styled. 43 References: - Eng. Asma Abdel Karim Computer Engineering Department, JU Slides. - Liang, Introduction to Java Programming 10/e Instructor: AbuKhleif, Mohammad Noor Sep 2017 End of Lecture =D AbuKhleiF - 22
Introduction to OOP with Java. Instructor: AbuKhleif, Mohammad Noor Sep 2017
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 07: OOP Part 1 Instructor: AbuKhleif, Mohammad Noor Sep 2017 Instructor AbuKhleif, Mohammad Noor Computer Engineer (JU
More informationIntroduction to OOP with Java. Instructor: AbuKhleif, Mohammad Noor Sep 2017
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 11: Inheritance and Polymorphism Part 1 Instructor: AbuKhleif, Mohammad Noor Sep 2017 Instructor AbuKhleif, Mohammad
More informationChapter 8 Objects and Classes
Chapter 8 Objects and Classes 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However, these Java
More informationChapter 8 Objects and Classes. Liang, Introduction to Java Programming, Ninth Edition, (c) 2013 Pearson Education, Inc. All rights reserved.
Chapter 8 Objects and Classes 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However, these Java
More informationIntroduction to OOP with Java. Instructor: AbuKhleif, Mohammad Noor Sep 2017
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 03: Control Flow Statements: Selection Instructor: AbuKhleif, Mohammad Noor Sep 2017 Instructor AbuKhleif, Mohammad Noor
More informationLiang, Introduction to Java Programming, Ninth Edition, (c) 2013 Pearson Education, Inc. All rights reserved.
Chapter 8 Objects and Classes Lecture notes for computer programming 1 Faculty of Engineering and Information Technology Prepared by: Iyad Albayouk 1 Motivations After learning the preceding chapters,
More informationIntroduction to OOP with Java. Instructor: AbuKhleif, Mohammad Noor Sep 2017
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 01: Introduction Instructor: AbuKhleif, Mohammad Noor Sep 2017 Instructor AbuKhleif, Mohammad Noor Studied Computer Engineer
More informationIntroduction. Introduction to OOP with Java. Lecture 01: Introduction to OOP with Java - AKF Sep AbuKhleiF -
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 www.abukhleif.com Lecture 01: Introduction Instructor: AbuKhleif, Mohammad Noor Sep 2017 www.abukhleif.com AbuKhleiF - www.abukhleif.com
More informationChapter 9 Objects and Classes. Liang, Introduction to Java Programming, Tenth Edition, (c) 2015 Pearson Education, Inc. All rights reserved.
Chapter 9 Objects and Classes rights reserved. 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However,
More informationUFCE3T-15-M Object-oriented Design and Programming
UFCE3T-15-M Object-oriented Design and Programming Block1: Objects and Classes Jin Sa 27-Sep-05 UFCE3T-15-M Programming part 1 Objectives To understand objects and classes and use classes to model objects.
More informationOO Programming Concepts
Chapter 8 Objects and Classes 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However, these Java
More informationChapter 9. Objects and Classes
Chapter 9 Objects and Classes 1 OO Programming in Java Other than primitive data types (byte, short, int, long, float, double, char, boolean), everything else in Java is of type object. Objects we already
More informationArrays. Introduction to OOP with Java. Lecture 06: Introduction to OOP with Java - AKF Sep AbuKhleiF - 1
Introduction to OOP with Java Instructor: AbuKhleif, Mohammad Noor Sep 2017 Lecture 06: Arrays Instructor: AbuKhleif, Mohammad Noor Sep 2017 AbuKhleiF - 1 Instructor AbuKhleif, Mohammad Noor Computer Engineer
More informationChapter 9 Objects and Classes. Liang, Introduction to Java Programming, Eleventh Edition, (c) 2017 Pearson Education, Inc. All rights reserved.
Chapter 9 Objects and Classes 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However, these Java
More informationChapter 9 Objects and Classes. OO Programming Concepts. Classes. Objects. Motivations. Objectives. CS1: Java Programming Colorado State University
Chapter 9 Objects and Classes CS1: Java Programming Colorado State University Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops,
More informationJAVA PROGRAMMING LAB. ABSTRACT In this Lab you will learn how to describe objects and classes and how to define classes and create objects
Islamic University of Gaza Faculty of Engineering Computer Engineering Dept Computer Programming Lab (ECOM 2114) ABSTRACT In this Lab you will learn how to describe objects and classes and how to define
More informationECOM 2324 COMPUTER PROGRAMMING II
ECOM 2324 COMPUTER PROGRAMMING II Object Oriented Programming with JAVA Instructor: Ruba A. Salamh Islamic University of Gaza 2 CHAPTER 9 OBJECTS AND CLASSES Motivations 3 After learning the preceding
More informationCIS3023: Programming Fundamentals for CIS Majors II Summer 2010
CIS3023: Programming Fundamentals for CIS Majors II Summer 2010 Objects and Classes (contd.) Course Lecture Slides 19 May 2010 Ganesh Viswanathan Objects and Classes Credits: Adapted from CIS3023 lecture
More informationAbstract Class. Lecture 21. Based on Slides of Dr. Norazah Yusof
Abstract Class Lecture 21 Based on Slides of Dr. Norazah Yusof 1 Abstract Class Abstract class is a class with one or more abstract methods. The abstract method Method signature without implementation
More informationChapter 3 Objects and Classes
Chapter 3 Objects and Classes Topics OO Programming Concepts Creating Objects and Object Reference Variables Constructors Modifiers Instance and Class Variables and Methods Scope of Variables OO Programming
More informationChapter 9 Objects and Classes. Liang, Introduction to C++ Programming, (c) 2007 Pearson Education, Inc. All rights reserved.
Chapter 9 Objects and Classes 1 Objectives Classes & Objects ( 9.2). UML ( 9.2). Constructors ( 9.3). How to declare a class & create an object ( 9.4). Separate a class declaration from a class implementation
More informationObject-Oriented Programming Concepts
Object-Oriented Programming Concepts Real world objects include things like your car, TV etc. These objects share two characteristics: they all have state and they all have behavior. Software objects are
More informationOO Programming Concepts. Classes. Objects. Chapter 8 User-Defined Classes and ADTs
Chapter 8 User-Defined Classes and ADTs Objectives To understand objects and classes and use classes to model objects To learn how to declare a class and how to create an object of a class To understand
More informationChapter 8 Objects and Classes
Chapter 8 Objects and Classes 1 Motivations After learning the preceding chapters, you are capable of solving many programming problems using selections, loops, methods, and arrays. However, these Java
More informationProgramming in the Large II: Objects and Classes (Part 1)
Programming in the Large II: Objects and Classes (Part 1) 188230 Advanced Computer Programming Asst. Prof. Dr. Kanda Runapongsa Saikaew (krunapon@kku.ac.th) Department of Computer Engineering Khon Kaen
More information2 What are the differences between constructors and methods?
1 Describe the relationship between an object and its defining class. How do you define a class? How do you declare an object reference variable? How do you create an object? How do you declare and create
More informationObject Oriented Programming in C#
Introduction to Object Oriented Programming in C# Class and Object 1 You will be able to: Objectives 1. Write a simple class definition in C#. 2. Control access to the methods and data in a class. 3. Create
More informationObject Oriented Programming. Java-Lecture 1
Object Oriented Programming Java-Lecture 1 Standard output System.out is known as the standard output object Methods to display text onto the standard output System.out.print prints text onto the screen
More informationChapter 10 Inheritance and Polymorphism. Dr. Hikmat Jaber
Chapter 10 Inheritance and Polymorphism Dr. Hikmat Jaber 1 Motivations Suppose you will define classes to model circles, rectangles, and triangles. These classes have many common features. What is the
More informationIn this lab, you will be given the implementation of the classes GeometricObject, Circle, and Rectangle, as shown in the following UML class diagram.
Jordan University Faculty of Engineering and Technology Department of Computer Engineering Object-Oriented Problem Solving: CPE 342 Lab-8 Eng. Asma Abdel Karim In this lab, you will be given the implementation
More informationCOMP200 ABSTRACT CLASSES. OOP using Java, from slides by Shayan Javed
1 1 COMP200 ABSTRACT CLASSES OOP using Java, from slides by Shayan Javed Abstract Classes 2 3 From the previous lecture: public class GeometricObject { protected String Color; protected String name; protected
More informationCH. 2 OBJECT-ORIENTED PROGRAMMING
CH. 2 OBJECT-ORIENTED PROGRAMMING ACKNOWLEDGEMENT: THESE SLIDES ARE ADAPTED FROM SLIDES PROVIDED WITH DATA STRUCTURES AND ALGORITHMS IN JAVA, GOODRICH, TAMASSIA AND GOLDWASSER (WILEY 2016) OBJECT-ORIENTED
More informationRecommended Group Brainstorm (NO computers during this time)
Recommended Group Brainstorm (NO computers during this time) Good programmers think before they begin coding. Part I of this assignment involves brainstorming with a group of peers with no computers to
More informationChapter 8 Objects and Classes Part 1
Chapter 8 Objects and Classes Part 1 1 OO Programming Concepts Object-oriented programming (OOP) involves programming using objects. An object represents an entity in the real world that can be distinctly
More informationCS 113 PRACTICE FINAL
CS 113 PRACTICE FINAL There are 13 questions on this test. The value of each question is: 1-10 multiple choice (4 pt) 11-13 coding problems (20 pt) You may get partial credit for questions 11-13. If you
More informationCOMP 250 Winter 2011 Reading: Java background January 5, 2011
Almost all of you have taken COMP 202 or equivalent, so I am assuming that you are familiar with the basic techniques and definitions of Java covered in that course. Those of you who have not taken a COMP
More informationInheritance and Polymorphism
Inheritance and Polymorphism Dr. M. G. Abbas Malik Assistant Professor Faculty of Computing and IT (North Jeddah Branch) King Abdulaziz University, Jeddah, KSA mgmalik@kau.edu.sa www.sanlp.org/malik/cpit305/ap.html
More informationI pledge by honor that I will not discuss this exam with anyone until my instructor reviews the exam in the class.
Name: Covers Chapters 1-3 50 mins CSCI 1301 Introduction to Programming Armstrong Atlantic State University Instructor: Dr. Y. Daniel Liang I pledge by honor that I will not discuss this exam with anyone
More informationOracle 1Z Java SE 8 Programmer I. Download Full Version :
Oracle 1Z0-808 Java SE 8 Programmer I Download Full Version : https://killexams.com/pass4sure/exam-detail/1z0-808 QUESTION: 121 And the commands: Javac Jump.java Java Jump crazy elephant is always What
More information1. Which of the following is the correct expression of character 4? a. 4 b. "4" c. '\0004' d. '4'
Practice questions: 1. Which of the following is the correct expression of character 4? a. 4 b. "4" c. '\0004' d. '4' 2. Will System.out.println((char)4) display 4? a. Yes b. No 3. The expression "Java
More informationNote: This is a miniassignment and the grading is automated. If you do not submit it correctly, you will receive at most half credit.
Com S 227 Fall 2018 Miniassignment 1 40 points Due Date: Friday, October 12, 11:59 pm (midnight) Late deadline (25% penalty): Monday, October 15, 11:59 pm General information This assignment is to be done
More informationJava Class Design. Eugeny Berkunsky, Computer Science dept., National University of Shipbuilding
Java Class Design Eugeny Berkunsky, Computer Science dept., National University of Shipbuilding eugeny.berkunsky@gmail.com http://www.berkut.mk.ua Objectives Implement encapsulation Implement inheritance
More informationInheritance and Polymorphism. CSE 114, Computer Science 1 Stony Brook University
Inheritance and Polymorphism CSE 114, Computer Science 1 Stony Brook University http://www.cs.stonybrook.edu/~cse114 1 Motivation Model classes with similar properties and methods: Circles, rectangles
More informationComputer Science II (20073) Week 1: Review and Inheritance
Computer Science II 4003-232-01 (20073) Week 1: Review and Inheritance Richard Zanibbi Rochester Institute of Technology Review of CS-I Hardware and Software Hardware Physical devices in a computer system
More informationCS61BL. Lecture 1: Welcome to CS61BL! Intro to Java and OOP Testing Error-handling
CS61BL Lecture 1: Welcome to CS61BL! Intro to Java and OOP Testing Error-handling About me Name: Edwin Liao Email: edliao@berkeley.edu Office hours: Thursday 3pm - 5pm Friday 11am - 1pm 611 Soda Or by
More informationCS 170, Section /3/2009 CS170, Section 000, Fall
Lecture 18: Objects CS 170, Section 000 3 November 2009 11/3/2009 CS170, Section 000, Fall 2009 1 Lecture Plan Homework 5 : questions, comments? Managing g g Data: objects to make your life easier ArrayList:
More informationConstructor. Liang, Introduction to Java Programming, Tenth Edition, (c) 2013 Pearson Education, Inc. All rights reserved.
Constructor Suppose you will define classes to model circles, rectangles, and triangles. These classes have many common features. What is the best way to design these classes so to avoid redundancy? The
More informationQuestions Answer Key Questions Answer Key Questions Answer Key
Benha University Term: 2 nd (2013/2014) Class: 2 nd Year Students Subject: Object Oriented Programming Faculty of Computers & Informatics Date: 26/4/2014 Time: 1 hours Exam: Mid-Term (A) Name:. Status:
More informationObjects and Classes. 1 Creating Classes and Objects. CSCI-UA 101 Objects and Classes
Based on Introduction to Java Programming, Y. Daniel Liang, Brief Version, 10/E 1 Creating Classes and Objects Classes give us a way of defining custom data types and associating data with operations on
More informationClasses and Objects 3/28/2017. How can multiple methods within a Java class read and write the same variable?
Peer Instruction 8 Classes and Objects How can multiple methods within a Java class read and write the same variable? A. Allow one method to reference a local variable of the other B. Declare a variable
More informationChapter 11 Inheritance and Polymorphism. Motivations. Suppose you will define classes to model circles,
Chapter 11 Inheritance and Polymorphism 1 Motivations Suppose you will define classes to model circles, rectangles, and triangles. These classes have many common features. What is the best way to design
More informationObject Oriented System Development Paradigm. Sunnie Chung CIS433 System Analysis Methods
Object Oriented System Development Paradigm Sunnie Chung CIS433 System Analysis Methods OO Programming Concepts Object-oriented programming (OOP) involves programming using objects. An object represents
More informationChapter 11 Inheritance and Polymorphism
Chapter 11 Inheritance and Polymorphism 1 Motivations OOP is built on three principles: Encapsulation (classes/objects, discussed in chapters 9 and 10), Inheritance, and Polymorphism. Inheritance: Suppose
More informationUniversity of Palestine. Mid Exam Total Grade: 100
First Question No. of Branches (5) A) Choose the correct answer: 1. If we type: system.out.println( a ); in the main() method, what will be the result? int a=12; //in the global space... void f() { int
More informationAnnouncement. Agenda 7/31/2008. Polymorphism, Dynamic Binding and Interface. The class will continue on Tuesday, 12 th August
Polymorphism, Dynamic Binding and Interface 2 4 pm Thursday 7/31/2008 @JD2211 1 Announcement Next week is off The class will continue on Tuesday, 12 th August 2 Agenda Review Inheritance Abstract Array
More informationCISC 3115 TY3. C09a: Inheritance. Hui Chen Department of Computer & Information Science CUNY Brooklyn College. 9/20/2018 CUNY Brooklyn College
CISC 3115 TY3 C09a: Inheritance Hui Chen Department of Computer & Information Science CUNY Brooklyn College 9/20/2018 CUNY Brooklyn College 1 Outline Inheritance Superclass/supertype, subclass/subtype
More informationChapter 11 Object-Oriented Design Exception and binary I/O can be covered after Chapter 9
Chapter 6 Arrays Chapter 7 Objects and Classes Chapter 8 Strings and Text I/O Chapter 9 Inheritance and Polymorphism GUI can be covered after 10.2, Abstract Classes Chapter 12 GUI Basics 10.2, Abstract
More informationIntroduction to Programming Using Python Lecture 4. Dr. Zhang COSC 1437 Fall, 2018 October 11, 2018
Introduction to Programming Using Python Lecture 4 Dr. Zhang COSC 1437 Fall, 2018 October 11, 2018 Chapter 7 Object-Oriented Programming Object-oriented programming (OOP) involves programming using objects.
More informationIntroduction to Classes and Objects
3 Nothing can have value without being an object of utility. Karl Marx Your public servants serve you right. Adlai E. Stevenson Knowing how to answer one who speaks, To reply to one who sends a message.
More informationInf1-OOP. Data Types. Defining Data Types in Java. type value set operations. Overview. Circle Class. Creating Data Types 1.
Overview Inf1-OOP Creating Data Types 1 Circle Class Object Default Perdita Stevens, adapting earlier version by Ewan Klein Format Strings School of Informatics January 11, 2015 HotelRoom Class More on
More informationCS1004: Intro to CS in Java, Spring 2005
CS1004: Intro to CS in Java, Spring 2005 Lecture #13: Java OO cont d. Janak J Parekh janak@cs.columbia.edu Administrivia Homework due next week Problem #2 revisited Constructors, revisited Remember: a
More informationNote: This is a miniassignment and the grading is automated. If you do not submit it correctly, you will receive at most half credit.
Com S 227 Spring 2018 Miniassignment 1 40 points Due Date: Thursday, March 8, 11:59 pm (midnight) Late deadline (25% penalty): Friday, March 9, 11:59 pm General information This assignment is to be done
More informationIntroduction to Java. Handout-1d. cs402 - Spring
Introduction to Java Handout-1d cs402 - Spring 2003 1 Methods (i) Method is the OOP name for function Must be declared always within a class optaccessqualifier returntype methodname ( optargumentlist )
More informationComments are almost like C++
UMBC CMSC 331 Java Comments are almost like C++ The javadoc program generates HTML API documentation from the javadoc style comments in your code. /* This kind of comment can span multiple lines */ //
More informationCS 112 Programming 2. Lecture 06. Inheritance & Polymorphism (1) Chapter 11 Inheritance and Polymorphism
CS 112 Programming 2 Lecture 06 Inheritance & Polymorphism (1) Chapter 11 Inheritance and Polymorphism rights reserved. 2 Motivation Suppose you want to define classes to model circles, rectangles, and
More informationObject Oriented Programming
Islamic University of Gaza Faculty of Engineering Computer Engineering Department Computer Programming Lab (ECOM 2114) Lab 11 Object Oriented Programming Eng. Mohammed Alokshiya December 16, 2014 Object-oriented
More informationMaking New instances of Classes
Making New instances of Classes NOTE: revised from previous version of Lecture04 New Operator Classes are user defined datatypes in OOP languages How do we make instances of these new datatypes? Using
More informationCOMP 250: Java Programming I. Carlos G. Oliver, Jérôme Waldispühl January 17-18, 2018 Slides adapted from M. Blanchette
COMP 250: Java Programming I Carlos G. Oliver, Jérôme Waldispühl January 17-18, 2018 Slides adapted from M. Blanchette Variables and types [Downey Ch 2] Variable: temporary storage location in memory.
More informationCreating and Using Objects
Creating and Using Objects 1 Fill in the blanks Object behaviour is described by, and object state is described by. Fill in the blanks Object behaviour is described by methods, and object state is described
More informationLecture 10 Declarations and Scope
Lecture 10 Declarations and Scope Declarations and Scope We have seen numerous qualifiers when defining methods and variables public private static final (we'll talk about protected when formally addressing
More informationLast lecture. Lecture 9. in a nutshell. in a nutshell 2. Example of encapsulation. Example of encapsulation. Class test. Procedural Programming
1 Lecture 9 Last lecture Class test Has been marked Collect your marks at your next seminar Seminars There are seminars this week to go through the class test Meet in the classroom indicated on the timetable
More informationChapter 14 Abstract Classes and Interfaces
Chapter 14 Abstract Classes and Interfaces 1 What is abstract class? Abstract class is just like other class, but it marks with abstract keyword. In abstract class, methods that we want to be overridden
More informationCS141 Programming Assignment #4
CS141 Programming Assignment #4 Due Sunday, Mar 3rd. 1) Create a class called Invoice that a hardware store might use to represent an invoice for an item sold at the store. An Invoice should include four
More informationException-Handling Overview
م.عبد الغني أبوجبل Exception Handling No matter how good a programmer you are, you cannot control everything. Things can go wrong. Very wrong. When you write a risky method, you need code to handle the
More informationObject Class. EX: LightSwitch Class. Basic Class Concepts: Parts. CS257 Computer Science II Kevin Sahr, PhD. Lecture 5: Writing Object Classes
1 CS257 Computer Science II Kevin Sahr, PhD Lecture 5: Writing Object Classes Object Class 2 objects are the basic building blocks of programs in Object Oriented Programming (OOP) languages objects consist
More informationChapter 11 Object-Oriented Design Exception and binary I/O can be covered after Chapter 9
Chapter 7 Objects and Classes Chapter 6 Arrays Chapter 7 Objects and Classes Chapter 8 Strings and Text I/O Chapter 9 Inheritance and Polymorphism GUI can be covered after 10.2, Abstract Classes Chapter
More informationClasses and Objects. CGS 3416 Spring 2018
Classes and Objects CGS 3416 Spring 2018 Classes and Objects An object is an encapsulation of data along with functions that act upon that data. It attempts to mirror the real world, where objects have
More informationProgramming by Delegation
Chapter 2 a Programming by Delegation I. Scott MacKenzie a These slides are mostly based on the course text: Java by abstraction: A client-view approach (4 th edition), H. Roumani (2015). 1 Topics What
More informationQuestions Answer Key Questions Answer Key Questions Answer Key
Benha University Term: 2 nd (2013/2014) Class: 2 nd Year Students Subject: Object Oriented Programming Faculty of Computers & Informatics Date: 26/4/2014 Time: 1 hours Exam: Mid-Term (B) Name:. Status:
More informationDocumenting, Using, and Testing Utility Classes
Documenting, Using, and Testing Utility Classes Readings: Chapter 2 of the Course Notes EECS2030: Advanced Object Oriented Programming Fall 2017 CHEN-WEI WANG Structure of Project: Packages and Classes
More informationChapter 21- Using Generics Case Study: Geometric Bunch. Class: Driver. package csu.matos; import java.util.arraylist; public class Driver {
Chapter 21- Using Generics Case Study: Geometric Bunch In this example a class called GeometricBunch is made to wrap around a list of GeometricObjects. Circle and Rectangle are subclasses of GeometricObject.
More informationInf1-OP. Creating Classes. Volker Seeker, adapting earlier version by Perdita Stevens and Ewan Klein. February 26, School of Informatics
Inf1-OP Creating Classes Volker Seeker, adapting earlier version by Perdita Stevens and Ewan Klein School of Informatics February 26, 2018 Creating classes Last time we saw how to use a class: create a
More informationChapter 11 Object-Oriented Design Exception and binary I/O can be covered after Chapter 9
Chapter 6 Arrays Chapter 7 Objects and Classes Chapter 8 Strings Chapter 9 Inheritance and Polymorphism GUI can be covered after 10.2, Abstract Classes Chapter 12 GUI Basics 10.2, Abstract Classes Chapter
More informationEECS168 Exam 3 Review
EECS168 Exam 3 Review Exam 3 Time: 2pm-2:50pm Monday Nov 5 Closed book, closed notes. Calculators or other electronic devices are not permitted or required. If you are unable to attend an exam for any
More informationComputer Science II Data Structures
Computer Science II Data Structures Instructor Sukumar Ghosh 201P Maclean Hall Office hours: 10:30 AM 12:00 PM Mondays and Fridays Course Webpage homepage.cs.uiowa.edu/~ghosh/2116.html Course Syllabus
More informationITI Introduction to Computing II
ITI 1121. Introduction to Computing II Marcel Turcotte School of Electrical Engineering and Computer Science Inheritance Introduction Generalization/specialization Version of January 20, 2014 Abstract
More informationClasses - 2. Data Processing Course, I. Hrivnacova, IPN Orsay
Classes - 2 Data Processing Course, I. Hrivnacova, IPN Orsay OOP, Classes Reminder Requirements for a Class Class Development Constructor Access Control Modifiers Getters, Setters Keyword this const Member
More informationCS1150 Principles of Computer Science Objects and Classes
CS1150 Principles of Computer Science Objects and Classes Yanyan Zhuang Department of Computer Science http://www.cs.uccs.edu/~yzhuang CS1150 UC. Colorado Springs Object-Oriented Thinking Chapters 1-8
More informationChapter 8 Objects and Classes Dr. Essam Halim Date: Page 1
Assignment (1) Chapter 8 Objects and Classes Dr. Essam Halim Date: 18-3-2014 Page 1 Section 8.2 Defining Classes for Objects 1 represents an entity in the real world that can be distinctly identified.
More informationHomework 6. Yuji Shimojo CMSC 330. Instructor: Prof. Reginald Y. Haseltine
Homework 6 Yuji Shimojo CMSC 330 Instructor: Prof. Reginald Y. Haseltine July 21, 2013 Question 1 What is the output of the following C++ program? #include #include using namespace
More informationQuestions Answer Key Questions Answer Key Questions Answer Key
Benha University Term: 2 nd (2013/2014) Class: 2 nd Year Students Subject: Object Oriented Programming Faculty of Computers & Informatics Date: 26/4/2014 Time: 1 hours Exam: Mid-Term (C) Name:. Status:
More informationIST311. Advanced Issues in OOP: Inheritance and Polymorphism
IST311 Advanced Issues in OOP: Inheritance and Polymorphism IST311/602 Cleveland State University Prof. Victor Matos Adapted from: Introduction to Java Programming: Comprehensive Version, Eighth Edition
More informationAssignment Marking Criteria
Assignment Marking Criteria Analysis Your analysis documentation must meet the following criteria: All program inputs, processing, and outputs. Each input and output must be given a name and description
More informationSimple Java Reference
Simple Java Reference This document provides a reference to all the Java syntax used in the Computational Methods course. 1 Compiling and running... 2 2 The main() method... 3 3 Primitive variable types...
More informationInheritance. Inheritance Reserved word protected Reserved word super Overriding methods Class Hierarchies Reading for this lecture: L&L
Inheritance Inheritance Reserved word protected Reserved word super Overriding methods Class Hierarchies Reading for this lecture: L&L 9.1 9.4 1 Inheritance Inheritance allows a software developer to derive
More informationCS61B Lecture #7. Announcements:
Announcements: CS61B Lecture #7 New discussion section: Tuesday 2 3PM in 310 Soda. New lab section: Thursday 2 4PM in 273 Soda. Programming Contest coming up: 5 October (new date). Watch for details. Last
More informationIntroduction to Classes and Objects How to manage data and actions together. Slides #10: Chapter
Topics 1) What is an object? What is a class? 2) How can we use objects? 3) How do we implement the functions of a class? Introduction to Classes and s How to manage data and actions together. Slides #10:
More information24. Inheritance. Java. Fall 2009 Instructor: Dr. Masoud Yaghini
24. Inheritance Java Fall 2009 Instructor: Dr. Masoud Yaghini Outline Superclasses and Subclasses Using the super Keyword Overriding Methods The Object Class References Superclasses and Subclasses Inheritance
More informationReusing Classes. Hendrik Speleers
Hendrik Speleers Overview Composition Inheritance Polymorphism Method overloading vs. overriding Visibility of variables and methods Specification of a contract Abstract classes, interfaces Software development
More informationQUIZ on Ch.5. Why is it sometimes not a good idea to place the private part of the interface in a header file?
QUIZ on Ch.5 Why is it sometimes not a good idea to place the private part of the interface in a header file? Example projects where we don t want the implementation visible to the client programmer: The
More information