Example of Object in Object Oriented Programming
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OOP with Java 16
OOP with Java 16. Inheritance and Overriding Thomas Weise · 汤卫思 [email protected] · http://iao.hfuu.edu.cn Hefei University, South Campus 2 合肥学院 南艳湖校区/南2区 Faculty of Computer Science and Technology 计算机科学与技术系 Institute of Applied Optimization 应用优化研究所 230601 Shushan District, Hefei, Anhui, China 中国 安徽省 合肥市 蜀山区 230601 Econ. & Tech. Devel. Zone, Jinxiu Dadao 99 经济技术开发区 锦绣大道99号 Outline 1 Introduction 2 Extending Classes and Class Hierarchy 3 Multi-Level Inheritance 4 The Class Object 5 static vs. instance methods 6 Summary website OOPwithJava ThomasWeise 2/23 Introduction • So far, we have basically treated as objects as data structures and used methods to work on them OOPwithJava ThomasWeise 3/23 Introduction • So far, we have basically treated as objects as data structures and used methods to work on them • But Object-Oriented Programming is much more OOPwithJava ThomasWeise 3/23 Introduction • So far, we have basically treated as objects as data structures and used methods to work on them • But Object-Oriented Programming is much more • The true power of OOP arises from class inheritance and extension (often called specialization) OOPwithJava ThomasWeise 3/23 Extending Classes • A class Student can extend another class Person OOPwithJava ThomasWeise 4/23 Extending Classes • A class Student can extend another class Person • Student inherits all the fields and functionality of the original class Person OOPwithJava ThomasWeise 4/23 Extending Classes • A class Student can extend another class Person • Student inherits all the fields and functionality -
Programming in JAVA Topic: • a Closer Look at Methods And
B. Sc. (H) Computer Science Semester II BHCS03 – Programming in JAVA Topic: A Closer Look at Methods and Classes Inheritance Command Line Arguments The java command-line argument is an argument i.e. passed at the time of running the java program. The arguments passed from the console can be received in the java program and it can be used as an input. So, it provides a convenient way to check the behavior of the program for the different values. You can pass N (1,2,3 and so on) numbers of arguments from the command prompt. Simple example of command-line argument In this example, we are receiving only one argument and printing it. To run this java program, you must pass at least one argument from the command prompt. class CommandLineExample{ public static void main(String args[]){ System.out.println("Your first argument is: "+args[0]); } } compile by > javac CommandLineExample.java run by > java CommandLineExample sonoo Output: Your first argument is: sonoo Varargs: Variable length arguments A method with variable length arguments(Varargs) in Java can have zero or multiple arguments. Variable length arguments are most useful when the number of arguments to be passed to the method is not known beforehand. They also reduce the code as overloaded methods are not required. Example public class Demo { public static void Varargs(String... str) { System.out.println("\nNumber of arguments are: " + str.length); System.out.println("The argument values are: "); for (String s : str) System.out.println(s); } public static void main(String args[]) { Varargs("Apple", "Mango", "Pear"); Varargs(); Varargs("Magic"); } } Output Number of arguments are: 3 The argument values are: Apple Mango Pear Number of arguments are: 0 The argument values are: Number of arguments are: 1 The argument values are: Magic Overloading Varargs Methods Overloading allows different methods to have same name, but different signatures where signature can differ by number of input parameters or type of input parameters or both. -
From Perl to Python
From Perl to Python Fernando Pineda 140.636 Oct. 11, 2017 version 0.1 3. Strong/Weak Dynamic typing The notion of strong and weak typing is a little murky, but I will provide some examples that provide insight most. Strong vs Weak typing To be strongly typed means that the type of data that a variable can hold is fixed and cannot be changed. To be weakly typed means that a variable can hold different types of data, e.g. at one point in the code it might hold an int at another point in the code it might hold a float . Static vs Dynamic typing To be statically typed means that the type of a variable is determined at compile time . Type checking is done by the compiler prior to execution of any code. To be dynamically typed means that the type of variable is determined at run-time. Type checking (if there is any) is done when the statement is executed. C is a strongly and statically language. float x; int y; # you can define your own types with the typedef statement typedef mytype int; mytype z; typedef struct Books { int book_id; char book_name[256] } Perl is a weakly and dynamically typed language. The type of a variable is set when it's value is first set Type checking is performed at run-time. Here is an example from stackoverflow.com that shows how the type of a variable is set to 'integer' at run-time (hence dynamically typed). $value is subsequently cast back and forth between string and a numeric types (hence weakly typed). -
Declare New Function Javascript
Declare New Function Javascript Piggy or embowed, Levon never stalemating any punctuality! Bipartite Amory wets no blackcurrants flagged anes after Hercules supinate methodically, quite aspirant. Estival Stanleigh bettings, his perspicaciousness exfoliating sopped enforcedly. How a javascript objects for mistakes to retain the closure syntax and maintainability of course, written by reading our customers and line? Everything looks very useful. These values or at first things without warranty that which to declare new function javascript? You declare a new class and news to a function expressions? Explore an implementation defined in new row with a function has a gas range. If it allows you probably work, regular expression evaluation but mostly warszawa, and to retain the explanation of. Reimagine your namespaces alone relate to declare new function javascript objects for arrow functions should be governed by programmers avoid purity. Js library in the different product topic and zip archives are. Why is selected, and declare a superclass method decorators need them into functions defined by allocating local time. It makes more sense to handle work in which support optional, only people want to preserve type to be very short term, but easier to! String type variable side effects and declarations take a more situations than or leading white list of merchantability or a way as explicit. You declare many types to prevent any ecmascript program is not have two categories by any of parameters the ecmascript is one argument we expect. It often derived from the new knowledge within the string, news and error if the function expression that their prototype. -
Module 3 Inheritance in Java
Module 3 Inheritance in Java Inheritance in java is a mechanism in which one object acquires all the properties and behaviors of parent object. The idea behind inheritance in java is that you can create new classes that are built upon existing classes. When you inherit from an existing class, you can reuse methods and fields of parent class, and you can add new methods and fields also. Inheritance represents the IS-A relationship, also known as parent-child relationship. For Method Overriding (so runtime polymorphism can be achieved). For Code Reusability. Syntax of Java Inheritance class Subclass-name extends Superclass-name { KTUNOTES.IN //methods and fields } The extends keyword indicates that you are making a new class that derives from an existing class. In the terminology of Java, a class that is inherited is called a super class. The new class is called a subclass. As displayed in the above figure, Programmer is the subclass and Employee is the superclass. Relationship between two classes is Programmer IS-A Employee.It means that Programmer is a type of Employee. class Employee{ float salary=40000; } class Programmer extends Employee{ int bonus=10000; public static void main(String args[]){ Programmer p=new Programmer(); System.out.println("Programmer salary is:"+p.salary); System.out.println("Bonus of Programmer is:"+p.bonus); } } Programmer salary is:40000.0 Bonus of programmer is:10000 In the above example, Programmer object can access the field of own class as well as of Employee class i.e. code reusability. Downloaded from Ktunotes.in Types of inheritance in java On the basis of class, there can be three types of inheritance in java: single, multilevel hierarchical. -
Scala by Example (2009)
Scala By Example DRAFT January 13, 2009 Martin Odersky PROGRAMMING METHODS LABORATORY EPFL SWITZERLAND Contents 1 Introduction1 2 A First Example3 3 Programming with Actors and Messages7 4 Expressions and Simple Functions 11 4.1 Expressions And Simple Functions...................... 11 4.2 Parameters.................................... 12 4.3 Conditional Expressions............................ 15 4.4 Example: Square Roots by Newton’s Method................ 15 4.5 Nested Functions................................ 16 4.6 Tail Recursion.................................. 18 5 First-Class Functions 21 5.1 Anonymous Functions............................. 22 5.2 Currying..................................... 23 5.3 Example: Finding Fixed Points of Functions................ 25 5.4 Summary..................................... 28 5.5 Language Elements Seen So Far....................... 28 6 Classes and Objects 31 7 Case Classes and Pattern Matching 43 7.1 Case Classes and Case Objects........................ 46 7.2 Pattern Matching................................ 47 8 Generic Types and Methods 51 8.1 Type Parameter Bounds............................ 53 8.2 Variance Annotations.............................. 56 iv CONTENTS 8.3 Lower Bounds.................................. 58 8.4 Least Types.................................... 58 8.5 Tuples....................................... 60 8.6 Functions.................................... 61 9 Lists 63 9.1 Using Lists.................................... 63 9.2 Definition of class List I: First Order Methods.............. -
Lambda Expressions
Back to Basics Lambda Expressions Barbara Geller & Ansel Sermersheim CppCon September 2020 Introduction ● Prologue ● History ● Function Pointer ● Function Object ● Definition of a Lambda Expression ● Capture Clause ● Generalized Capture ● This ● Full Syntax as of C++20 ● What is the Big Deal ● Generic Lambda 2 Prologue ● Credentials ○ every library and application is open source ○ development using cutting edge C++ technology ○ source code hosted on github ○ prebuilt binaries are available on our download site ○ all documentation is generated by DoxyPress ○ youtube channel with over 50 videos ○ frequent speakers at multiple conferences ■ CppCon, CppNow, emBO++, MeetingC++, code::dive ○ numerous presentations for C++ user groups ■ United States, Germany, Netherlands, England 3 Prologue ● Maintainers and Co-Founders ○ CopperSpice ■ cross platform C++ libraries ○ DoxyPress ■ documentation generator for C++ and other languages ○ CsString ■ support for UTF-8 and UTF-16, extensible to other encodings ○ CsSignal ■ thread aware signal / slot library ○ CsLibGuarded ■ library for managing access to data shared between threads 4 Lambda Expressions ● History ○ lambda calculus is a branch of mathematics ■ introduced in the 1930’s to prove if “something” can be solved ■ used to construct a model where all functions are anonymous ■ some of the first items lambda calculus was used to address ● if a sequence of steps can be defined which solves a problem, then can a program be written which implements the steps ○ yes, always ● can any computer hardware -
PHP Advanced and Object-Oriented Programming
VISUAL QUICKPRO GUIDE PHP Advanced and Object-Oriented Programming LARRY ULLMAN Peachpit Press Visual QuickPro Guide PHP Advanced and Object-Oriented Programming Larry Ullman Peachpit Press 1249 Eighth Street Berkeley, CA 94710 Find us on the Web at: www.peachpit.com To report errors, please send a note to: [email protected] Peachpit Press is a division of Pearson Education. Copyright © 2013 by Larry Ullman Acquisitions Editor: Rebecca Gulick Production Coordinator: Myrna Vladic Copy Editor: Liz Welch Technical Reviewer: Alan Solis Compositor: Danielle Foster Proofreader: Patricia Pane Indexer: Valerie Haynes Perry Cover Design: RHDG / Riezebos Holzbaur Design Group, Peachpit Press Interior Design: Peachpit Press Logo Design: MINE™ www.minesf.com Notice of Rights All rights reserved. No part of this book may be reproduced or transmitted in any form by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. For information on getting permission for reprints and excerpts, contact [email protected]. Notice of Liability The information in this book is distributed on an “As Is” basis, without warranty. While every precaution has been taken in the preparation of the book, neither the author nor Peachpit Press shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the instructions contained in this book or by the computer software and hardware products described in it. Trademarks Visual QuickPro Guide is a registered trademark of Peachpit Press, a division of Pearson Education. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. -
Conformity Behavior of Dissimilar Methods for Object Oriented
K. LOUZAOUUI Conformity behavior of dissimilar methods for object oriented constraint programming 212 Conformity Behavior of Dissimilar Methods for Object Oriented Constraint Programming Khadija Louzaoui Khalid Benlhachmi Department of Mathematics Department of Computer Sciences Faculty of Sciences, Ibn Tofail University Faculty of Sciences, Ibn Tofail University Kenitra, Morocco Kenitra, Morocco Abstract—This paper presents an approach for testing the number of test cases is infinite, therefore, testing is very conformity of overridden and overriding methods using expensive. So, how to select the most proper set of test cases? inheritance principle. The first objective of this work is the In practice, various techniques are used for that, some of them reduction of the test sequences by using only one generation of are based on the specification of the program under test using test data. The second result is the conformity testing of methods precondition, postcondition and invariant constraints. In this even if they are not similar: Our approach shows how the similarity partitioning can be used for testing not the similarity way the specifications by constraints in an object oriented behavior between methods but the conformity behavior of paradigm can be specified by formal languages as OCL [3] and subclasses for an object oriented model. JML [4], and are used for generating test data from formal specifications [5]. This software verification by constraints can In this work we use a mathematical modeling such as domain help for creating a mathematical modeling and building the partitioning and states graph for testing the conformity of parts of different classes of errors (equivalence partitioning). -
JAVA - OVERRIDING Copyright © Tutorialspoint.Com
JAVA - OVERRIDING http://www.tutorialspoint.com/java/java_overriding.htm Copyright © tutorialspoint.com In the previous chapter, we talked about super classes and sub classes. If a class inherits a method from its super class, then there is a chance to override the method provided that it is not marked final. The benefit of overriding is: ability to define a behavior that's specific to the subclass type which means a subclass can implement a parent class method based on its requirement. In object-oriented terms, overriding means to override the functionality of an existing method. Example: Let us look at an example. class Animal{ public void move(){ System.out.println("Animals can move"); } } class Dog extends Animal{ public void move(){ System.out.println("Dogs can walk and run"); } } public class TestDog{ public static void main(String args[]){ Animal a = new Animal(); // Animal reference and object Animal b = new Dog(); // Animal reference but Dog object a.move();// runs the method in Animal class b.move();//Runs the method in Dog class } } This would produce the following result: Animals can move Dogs can walk and run In the above example, you can see that the even though b is a type of Animal it runs the move method in the Dog class. The reason for this is: In compile time, the check is made on the reference type. However, in the runtime, JVM figures out the object type and would run the method that belongs to that particular object. Therefore, in the above example, the program will compile properly since Animal class has the method move. -
Chapter 15. Javascript 4: Objects and Arrays
Chapter 15. JavaScript 4: Objects and Arrays Table of Contents Objectives .............................................................................................................................................. 2 15.1 Introduction .............................................................................................................................. 2 15.2 Arrays ....................................................................................................................................... 2 15.2.1 Introduction to arrays ..................................................................................................... 2 15.2.2 Indexing of array elements ............................................................................................ 3 15.2.3 Creating arrays and assigning values to their elements ................................................. 3 15.2.4 Creating and initialising arrays in a single statement ..................................................... 4 15.2.5 Displaying the contents of arrays ................................................................................. 4 15.2.6 Array length ................................................................................................................... 4 15.2.7 Types of values in array elements .................................................................................. 6 15.2.8 Strings are NOT arrays .................................................................................................. 7 15.2.9 Variables — primitive -
Method Overriding
Method Overriding OOC 4th Sem, ‘B’ Div 2016-17 Prof. Mouna M. Naravani ➢ In a class hierarchy, when a method in a subclass has the same name and type signature as a method in its superclass, then the method in the subclass is said to override the method in the superclass. ➢ When an overridden method is called from within a subclass, it will always refer to the version of that method defined by the subclass. ➢ The version of the method defined by the superclass will be hidden. class A { class B extends A { int i, j; int k; A(int a, int b) { B(int a, int b, int c) { i = a; super(a, b); j = b; k = c; } } // display i and j // display k -- this overrides show() in A void show() { void show() { System.out.println("i and j: " + i + " " + j); System.out.println("k: " + k); } } } } class Override { Output: public static void main(String args[]) k : 3 { B subOb = new B(1, 2, 3); subOb.show(); // this calls show() in B } } ➢ When show( ) is invoked on an object of type B, the version of show( ) defined within B is used. ➢ That is, the version of show( ) inside B overrides the version declared in A. ➢ If you wish to access the superclass version of an overridden method, you can do so by using super. class B extends A { int k; B(int a, int b, int c) { super(a, b); Output: k = c; i and j : 1 2 } k : 3 void show() { super.show(); // this calls A's show() System.out.println("k: " + k); } } ➢ Method overriding occurs only when the names and the type signatures of the two methods are identical.