Lecture

Collections: Hashcode and Equals Methods

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In course

CS-108: Practice of object-oriented programming

Les étudiants perfectionnent leurs connaissances en Java et les mettent en pratique en réalisant un projet de taille conséquente. Ils apprennent à utiliser et à mettre en œuvre les principaux types de collections (listes, ensembles, tables associatives), e ...

Description

This lecture covers the implementation of hashcode and equals methods in Java, emphasizing the importance of compatibility between them. It explains how hash values and object equality are related, highlighting the need for caution in their usage. The instructor demonstrates these concepts through code examples and discusses the implications of not following the compatibility rule.

Instructor

Michel Schinz

Teaching & PhD Courses Advanced compiler construction CS-420 Students learn several implementation techniques for modern functional and object-oriented programming languages. They put some of them into practice by developing key parts of a compiler and run time system for a simple functional programming language. Practice of object-oriented programming CS-108 Students improve their knowledge of Java and put it into practice by implementing a sizeable project. They learn how t

Official source

Ontological neighbourhood

Theoretical computer science

Programming language theory: High-level programming languages

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Java (software platform)

Java is a set of computer software and specifications developed by James Gosling at Sun Microsystems that provides a system for developing application software and deploying it in a cross-platform computing environment. Java is used in a wide variety of computing platforms from embedded devices and mobile phones to enterprise servers and supercomputers. Java applets, which are less common than standalone Java applications, were commonly run in secure, sandboxed environments to provide many features of native applications through being embedded in HTML pages.

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The Java language has undergone several changes since JDK 1.0 as well as numerous additions of classes and packages to the standard library. Since J2SE 1.4, the evolution of the Java language has been governed by the Java Community Process (JCP), which uses Java Specification Requests (JSRs) to propose and specify additions and changes to the Java platform. The language is specified by the Java Language Specification (JLS); changes to the JLS are managed under JSR 901.

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