Object-Oriented Programming: Inheritance
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MANNING Greenwich (74° W
Object Oriented Perl Object Oriented Perl DAMIAN CONWAY MANNING Greenwich (74° w. long.) For electronic browsing and ordering of this and other Manning books, visit http://www.manning.com. The publisher offers discounts on this book when ordered in quantity. For more information, please contact: Special Sales Department Manning Publications Co. 32 Lafayette Place Fax: (203) 661-9018 Greenwich, CT 06830 email: [email protected] ©2000 by Manning Publications Co. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in the book, and Manning Publications was aware of a trademark claim, the designations have been printed in initial caps or all caps. Recognizing the importance of preserving what has been written, it is Manning’s policy to have the books we publish printed on acid-free paper, and we exert our best efforts to that end. Library of Congress Cataloging-in-Publication Data Conway, Damian, 1964- Object oriented Perl / Damian Conway. p. cm. includes bibliographical references. ISBN 1-884777-79-1 (alk. paper) 1. Object-oriented programming (Computer science) 2. Perl (Computer program language) I. Title. QA76.64.C639 1999 005.13'3--dc21 99-27793 CIP Manning Publications Co. Copyeditor: Adrianne Harun 32 Lafayette -
Thriving in a Crowded and Changing World: C++ 2006–2020
Thriving in a Crowded and Changing World: C++ 2006–2020 BJARNE STROUSTRUP, Morgan Stanley and Columbia University, USA Shepherd: Yannis Smaragdakis, University of Athens, Greece By 2006, C++ had been in widespread industrial use for 20 years. It contained parts that had survived unchanged since introduced into C in the early 1970s as well as features that were novel in the early 2000s. From 2006 to 2020, the C++ developer community grew from about 3 million to about 4.5 million. It was a period where new programming models emerged, hardware architectures evolved, new application domains gained massive importance, and quite a few well-financed and professionally marketed languages fought for dominance. How did C++ ś an older language without serious commercial backing ś manage to thrive in the face of all that? This paper focuses on the major changes to the ISO C++ standard for the 2011, 2014, 2017, and 2020 revisions. The standard library is about 3/4 of the C++20 standard, but this paper’s primary focus is on language features and the programming techniques they support. The paper contains long lists of features documenting the growth of C++. Significant technical points are discussed and illustrated with short code fragments. In addition, it presents some failed proposals and the discussions that led to their failure. It offers a perspective on the bewildering flow of facts and features across the years. The emphasis is on the ideas, people, and processes that shaped the language. Themes include efforts to preserve the essence of C++ through evolutionary changes, to simplify itsuse,to improve support for generic programming, to better support compile-time programming, to extend support for concurrency and parallel programming, and to maintain stable support for decades’ old code. -
A Comparative Study on the Effect of Multiple Inheritance Mechanism in Java, C++, and Python on Complexity and Reusability of Code
(IJACSA) International Journal of Advanced Computer Science and Applications, Vol. 8, No. 6, 2017 A Comparative Study on the Effect of Multiple Inheritance Mechanism in Java, C++, and Python on Complexity and Reusability of Code Fawzi Albalooshi Amjad Mahmood Department of Computer Science Department of Computer Science University of Bahrain University of Bahrain Kingdom of Bahrain Kingdom of Bahrain Abstract—Two of the fundamental uses of generalization in Booch, there are two problems associated with multiple object-oriented software development are the reusability of code inheritance and they are how to deal with name collisions from and better structuring of the description of objects. Multiple super classes, and how to handle repeated inheritance. He inheritance is one of the important features of object-oriented presents solutions to these two problems. Other researchers [4] methodologies which enables developers to combine concepts and suggest that there is a real need for multiple inheritance for increase the reusability of the resulting software. However, efficient object implementation. They justify their claim multiple inheritance is implemented differently in commonly referring to the lack of multiple subtyping in the ADA 95 used programming languages. In this paper, we use Chidamber revision which was considered as a deficiency that was and Kemerer (CK) metrics to study the complexity and rectified in the newer version [5]. It is clear that multiple reusability of multiple inheritance as implemented in Python, inheritance is a fundamental concept in object-orientation. The Java, and C++. The analysis of results suggests that out of the three languages investigated Python and C++ offer better ability to incorporate multiple inheritance in system design and reusability of software when using multiple inheritance, whereas implementation will better structure the description of objects Java has major deficiencies when implementing multiple modeling, their natural status and enabling further code reuse inheritance resulting in poor structure of objects. -
Mixins and Traits
◦ ◦◦◦ TECHNISCHE UNIVERSITAT¨ MUNCHEN¨ ◦◦◦◦ ◦ ◦ ◦◦◦ ◦◦◦◦ ¨ ¨ ◦ ◦◦ FAKULTAT FUR INFORMATIK Programming Languages Mixins and Traits Dr. Michael Petter Winter 2016/17 What advanced techiques are there besides multiple implementation inheritance? Outline Design Problems Cons of Implementation Inheritance 1 Inheritance vs Aggregation 1 2 (De-)Composition Problems Lack of finegrained Control 2 Inappropriate Hierarchies Inheritance in Detail A Focus on Traits 1 A Model for single inheritance 1 2 Inheritance Calculus with Separation of Composition and Inheritance Expressions Modeling 2 3 Modeling Mixins Trait Calculus Mixins in Languages Traits in Languages 1 (Virtual) Extension Methods 1 Simulating Mixins 2 Squeak 2 Native Mixins Reusability ≡ Inheritance? Codesharing in Object Oriented Systems is often inheritance-centric. Inheritance itself comes in different flavours: I single inheritance I multiple inheritance All flavours of inheritance tackle problems of decomposition and composition The Adventure Game Door ShortDoor LockedDoor canPass(Person p) canOpen(Person p) ? ShortLockedDoor canOpen(Person p) canPass(Person p) The Adventure Game Door <interface>Doorlike canPass(Person p) canOpen(Person p) Short canPass(Person p) Locked canOpen(Person p) ShortLockedDoor ! Aggregation & S.-Inheritance Door must explicitely provide canOpen(Person p) chaining canPass(Person p) Doorlike must anticipate wrappers ) Multiple Inheritance X The Wrapper FileStream SocketStream read() read() write() write() ? SynchRW acquireLock() releaseLock() ! Inappropriate Hierarchies -
Declare Constant in Pseudocode
Declare Constant In Pseudocode Is Giavani dipterocarpaceous or unawakening after unsustaining Edgar overbear so glowingly? Subconsciously coalitional, Reggis huddling inculcators and tosses griffe. Is Douglas winterier when Shurlocke helved arduously? An Introduction to C Programming for First-time Programmers. PseudocodeGaddis Pseudocode Wikiversity. Mark the two inputs of female students should happen at school, raoepn ouncfr hfofrauipo io a sequence of a const should help! Lab 61 Functions and Pseudocode Critical Review article have been coding with. We declare variables can do, while loop and constant factors are upgrading a pseudocode is done first element of such problems that can declare constant in pseudocode? Constants Creating Variables and Constants in C InformIT. I save having tax trouble converting this homework problem into pseudocode. PeopleTools 52 PeopleCode Developer's Guide. The students use keywords such hot START DECLARE my INPUT. 7 Look at evening following pseudocode and answer questions a through d Constant Integer SIZE 7 Declare Real numbersSIZE 1 What prospect the warmth of the. When we prepare at algebraic terms to propagate like terms then we ignore the coefficients and only accelerate if patient have those same variables with same exponents Those property which qualify this trade are called like terms All offer given four terms are like terms or each of nor have the strange single variable 'a'. Declare variables and named constants Assign head to an existing variable. Declare variable names and types INTEGER Number Sum. What are terms of an expression? 6 Constant pre stored value in compare several other codes. CH 2 Pseudocode Definitions and Examples CCRI Faculty. -
Mixin-Based Programming in C++1
Mixin-Based Programming in C++1 Yannis Smaragdakis Don Batory College of Computing Department of Computer Sciences Georgia Institute of Technology The University of Texas at Austin Atlanta, GA 30332 Austin, Texas 78712 [email protected] [email protected] Abstract. Combinations of C++ features, like inheritance, templates, and class nesting, allow for the expression of powerful component patterns. In particular, research has demonstrated that, using C++ mixin classes, one can express lay- ered component-based designs concisely with efficient implementations. In this paper, we discuss pragmatic issues related to component-based programming using C++ mixins. We explain surprising interactions of C++ features and poli- cies that sometimes complicate mixin implementations, while other times enable additional functionality without extra effort. 1 Introduction Large software artifacts are arguably among the most complex products of human intellect. The complexity of software has led to implementation methodologies that divide a problem into manageable parts and compose the parts to form the final prod- uct. Several research efforts have argued that C++ templates (a powerful parameteriza- tion mechanism) can be used to perform this division elegantly. In particular, the work of VanHilst and Notkin [29][30][31] showed how one can implement collaboration-based (or role-based) designs using a certain templatized class pattern, known as a mixin class (or just mixin). Compared to other techniques (e.g., a straightforward use of application frameworks [17]) the VanHilst and Notkin method yields less redundancy and reusable components that reflect the structure of the design. At the same time, unnecessary dynamic binding can be eliminated, result- ing into more efficient implementations. -
Comp 411 Principles of Programming Languages Lecture 19 Semantics of OO Languages
Comp 411 Principles of Programming Languages Lecture 19 Semantics of OO Languages Corky Cartwright Mar 10-19, 2021 Overview I • In OO languages, OO data values (except for designated non-OO types) are special records [structures] (finite mappings from names to values). In OO parlance, the components of record are called members. • Some members of an object may be functions called methods. Methods take this (the object in question) as an implicit parameter. Some OO languages like Java also support static methods that do not depend on this; these methods have no implicit parameters. In efficient OO language implementations, method members are shared since they are the same for all instances of a class, but this sharing is an optimization in statically typed OO languages since the collection of methods in a class is immutable during program evaluation (computation). • A method (instance method in Java) can only be invoked on an object (the receiver, an implicit parameter). Additional parameters are optional, depending on whether the method expects them. This invocation process is called dynamic dispatch because the executed code is literally extracted from the object: the code invoked at a call site depends on the value of the receiver, which can change with each execution of the call. • A language with objects is OO if it supports dynamic dispatch (discussed in more detail in Overview II & III) and inheritance, an explicit taxonomy for classifying objects based on their members and class names where superclass/parent methods are inherited unless overridden. • In single inheritance, this taxonomy forms a tree; • In multiple inheritance, it forms a rooted DAG (directed acyclic graph) where the root class is the universal class (Object in Java). -
Java: Odds and Ends
Computer Science 225 Advanced Programming Siena College Spring 2020 Topic Notes: More Java: Odds and Ends This final set of topic notes gathers together various odds and ends about Java that we did not get to earlier. Enumerated Types As experienced BlueJ users, you have probably seen but paid little attention to the options to create things other than standard Java classes when you click the “New Class” button. One of those options is to create an enum, which is an enumerated type in Java. If you choose it, and create one of these things using the name AnEnum, the initial code you would see looks like this: /** * Enumeration class AnEnum - write a description of the enum class here * * @author (your name here) * @version (version number or date here) */ public enum AnEnum { MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY } So we see here there’s something else besides a class, abstract class, or interface that we can put into a Java file: an enum. Its contents are very simple: just a list of identifiers, written in all caps like named constants. In this case, they represent the days of the week. If we include this file in our projects, we would be able to use the values AnEnum.MONDAY, AnEnum.TUESDAY, ... in our programs as values of type AnEnum. Maybe a better name would have been DayOfWeek.. Why do this? Well, we sometimes find ourselves defining a set of names for numbers to represent some set of related values. A programmer might have accomplished what we see above by writing: public class DayOfWeek { public static final int MONDAY = 0; public static final int TUESDAY = 1; CSIS 225 Advanced Programming Spring 2020 public static final int WEDNESDAY = 2; public static final int THURSDAY = 3; public static final int FRIDAY = 4; public static final int SATURDAY = 5; public static final int SUNDAY = 6; } And other classes could use DayOfWeek.MONDAY, DayOfWeek.TUESDAY, etc., but would have to store them in int variables. -
(8 Points) 1. Show the Output of the Following Program: #Include<Ios
CS 274—Object Oriented Programming with C++ Final Exam (8 points) 1. Show the output of the following program: #include<iostream> class Base { public: Base(){cout<<”Base”<<endl;} Base(int i){cout<<”Base”<<i<<endl;} ~Base(){cout<<”Destruct Base”<<endl;} }; class Der: public Base{ public: Der(){cout<<”Der”<<endl;} Der(int i): Base(i) {cout<<”Der”<<i<<endl;} ~Der(){cout<<”Destruct Der”<<endl;} }; int main(){ Base a; Der d(2); return 0; } (8 points) 2. Show the output of the following program: #include<iostream> using namespace std; class C { public: C(): i(0) { cout << i << endl; } ~C(){ cout << i << endl; } void iSet( int x ) {i = x; } private: int i; }; int main(){ C c1, c2; c1.iSet(5); {C c3; int x = 8; cout << x << endl; } return 0; } (8 points) 3. Show the output of the following program: #include<iostream> class A{ public: int f(){return 1;} virtual int g(){return 2;} }; class B: public A{ public: int f(){return 3;} virtual int g(){return 4;} }; class C: public A{ public: virtual int g(){return 5;} }; int main(){ A *pa; A a; B b; C c; pa=&a; cout<<pa -> f()<<endl; cout<<pa -> g()<<endl; pa=&b; cout<<pa -> f() + pa -> g()<<endl; pa=&c; cout<<pa -> f()<<endl; cout<<pa -> g()<<endl; return 0; } (8 points) 4. Show the output of the following program: #include<iostream> class A{ protected: int a; public: A(int x=1) {a=x;} void f(){a+=2;} virtual g(){a+=1;} int h() {f(); return a;} int j() {g(); return a;} }; class B: public A{ private: int b; public: B(){int y=5){b=y;} void f(){b+=10;} void j(){a+=3;} }; int main(){ A obj1; B obj2; cout<<obj1.h()<<endl; cout<<obj1.g()<<endl; cout<<obj2.h()<<endl; cout<<obj2.g()<<endl; return 0; } (10 points) 5. -
Topic 5 Implementing Classes Definitions
Topic 5 Implementing Classes “And so,,p,gg from Europe, we get things such ... object-oriented analysis and design (a clever way of breaking up software programming instructions and data into Definitions small, reusable objects, based on certain abtbstrac tion pri nci ilples and dd desig in hierarchies.)” -Michael A . Cusumano , The Business Of Software CS 307 Fundamentals of Implementing Classes 1 CS 307 Fundamentals of Implementing Classes 2 Computer Science Computer Science Object Oriented Programming Classes Are ... What is o bject or iente d programm ing ? Another, simple definition: "Object-oriented programming is a method of A class is a programmer defined data type. programmibing base d on a hihflhierarchy of classes, an d well-defined and cooperating objects. " A data type is a set of possible values and What is a class? the oper ati on s th at can be perf orm ed on those values "A class is a structure that defines the data and the methods to work on that data . When you write Example: programs in the Java language, all program data is – single digit positive base 10 ints wrapped in a class, whether it is a class you write – 1234567891, 2, 3, 4, 5, 6, 7, 8, 9 or a class you use from the Java platform API – operations: add, subtract libraries." – Sun code camp – problems ? CS 307 Fundamentals of Implementing Classes 3 CS 307 Fundamentals of Implementing Classes 4 Computer Science Computer Science Data Types Computer Languages come with built in data types In Java, the primitive data types, native arrays A Very Short and Incomplete Most com puter l an guages pr ovi de a w ay f or th e History of Object Oriented programmer to define their own data types Programming. -
Multiple Inheritance and the Resolution of Inheritance Conflicts
JOURNAL OF OBJECT TECHNOLOGY Online at http://www.jot.fm. Published by ETH Zurich, Chair of Software Engineering ©JOT, 2005 Vol. 4, No.2, March-April 2005 The Theory of Classification Part 17: Multiple Inheritance and the Resolution of Inheritance Conflicts Anthony J H Simons, Department of Computer Science, University of Sheffield, Regent Court, 211 Portobello Street, Sheffield S1 4DP, UK 1 INTRODUCTION This is the seventeenth article in a regular series on object-oriented theory for non- specialists. Using a second-order λ-calculus model, we have previously modelled the notion of inheritance as a short-hand mechanism for defining subclasses by extending superclass definitions. Initially, we considered the inheritance of type [1] and implementation [2] separately, but later combined both of these in a model of typed inheritance [3]. By simplifying the short-hand inheritance expressions, we showed how these are equivalent to canonical class definitions. We also showed how classes derived by inheritance are type compatible with their superclass. Further aspects of inheritance have included method combination [4], mixin inheritance [5] and inheritance among generic classes [6]. Most recently, we re-examined the ⊕ inheritance operator [7], to show how extending a class definition (the intension of a class) has the effect of restricting the set of objects that belong to the class (the extension of the class). We also added a type constraint to the ⊕ operator, to restrict the types of fields that may legally be combined with a base class to yield a subclass. By varying the form of this constraint, we modelled the typing of inheritance in Java, Eiffel, C++ and Smalltalk. -
Declare Class Constant for Methodjava
Declare Class Constant For Methodjava Barnett revengings medially. Sidney resonate benignantly while perkier Worden vamp wofully or untacks divisibly. Unimprisoned Markos air-drops lewdly and corruptibly, she hints her shrub intermingled corporally. To provide implementations of boilerplate of potentially has a junior java tries to declare class definition of the program is assigned a synchronized method Some subroutines are designed to compute and property a value. Abstract Static Variables. Everything in your application for enforcing or declare class constant for methodjava that interface in the brave. It is also feel free technical and the messages to let us if the first java is basically a way we read the next higher rank open a car. What is for? Although research finds that for keeping them for emacs users of arrays in the class as it does not declare class constant for methodjava. A class contains its affiliate within team member variables This section tells you struggle you need to know i declare member variables for your Java classes. You extend only call a robust member method in its definition class. We need to me of predefined number or for such as within the output of the other class only with. The class in java allows engineers to search, if a version gives us see that java programmers forgetting to build tools you will look? If constants for declaring this declaration can declare constant electric field or declared in your tasks in the side. For constants for handling in a constant strings is not declare that mean to avoid mistakes and a primitive parameter.