Object (computer science)

In software development, an object is an entity semantic that has state, behavior, and identity. <ref name="ooa">Template:Cite book</ref><ref name="Why Natural Scientists Should Care About Object-Oriented Technology">http://www.literateprogramming.com/quantumoo.pdf</ref><ref name='Distributed Object-Based Programming Systems">https://dl.acm.org/doi/pdf/10.1145/103162.103165</ref><ref>https://dl.acm.org/doi/pdf/10.1145/38807.38823</ref> An object can model some part of reality or can be an invention of the design process whose collaborations with other such objects serve as the mechanisms that provide some higher-level behavior. Put another way, an object represents an individual, identifiable item, unit, or entity, either real or abstract, with a well-defined role in the problem domain.<ref name="ooa"></ref>Template:Rp

A programming language can be classified based on its support for objects. A language that provides an encapsulation construct for state, behavior, and identity is classified as object-based. If the language also provides polymorphism and inheritance it is classified as object-oriented.<ref>https://www.eng.uwo.ca/electrical/faculty/capretz_l/docs/publications/ACM-SIGSOFT-v2.pdf</ref>Template:Dubious A language that supports creating an object from a class is classified as class-based. A language that supports object creation via a template object is classified as prototype-based.

The concept of object is used in many different software contexts, including:

• Possibly the most common use is in-memory objects in a computer program written in an object-based language.

• Information systems can be modeled with objects representing their components and interfaces.<ref name="ooa"/>Template:Rp

• In the relational model of database management, aspects such as table and column may act as objects.<ref name=Oppel>Template:Cite book</ref>

• Objects of a distributed computing system tend to be larger grained, longer lasting, and more service-oriented than programming objects.

In purely object-oriented programming languages, such as Java and C#, all classes might be part of an inheritance tree such that the root class is Object, meaning all objects instances of Object or implicitly extend Object.

External links

• What Is an Object? from The Java Tutorials