59-647: [REDACTED] Look up oop or OOP in Wiktionary, the free dictionary. OOP , Oop , or oop may refer to: Science and technology [ edit ] Object-oriented positioning , another name for feature-oriented positioning in microscopy Object-oriented programming , a computer programming paradigm Order of operations , in mathematics, rules for which parts of an expression are evaluated first Out of position (crash testing) Others [ edit ] Order of play, schedule of contests in
118-775: A tennis event Out-of-pocket expenses , in health care, are expenses that the insured party must pay directly to the health care provider Out of position, in poker a disadvantageous poker position in the order of play Out of print , a term referring to a book or other work that is no longer being published Oop!, a software idea in Douglas Coupland's novel Microserfs Restraining order , also known as an order of protection or OOP See also [ edit ] Alley Oop (disambiguation) Objectives Oriented Project Planning , in project management OOPP , out-of-process plug-ins in computer software applications Oops (disambiguation) Topics referred to by
177-415: A computer programming paradigm Order of operations , in mathematics, rules for which parts of an expression are evaluated first Out of position (crash testing) Others [ edit ] Order of play, schedule of contests in a tennis event Out-of-pocket expenses , in health care, are expenses that the insured party must pay directly to the health care provider Out of position, in poker
236-535: A disadvantageous poker position in the order of play Out of print , a term referring to a book or other work that is no longer being published Oop!, a software idea in Douglas Coupland's novel Microserfs Restraining order , also known as an order of protection or OOP See also [ edit ] Alley Oop (disambiguation) Objectives Oriented Project Planning , in project management OOPP , out-of-process plug-ins in computer software applications Oops (disambiguation) Topics referred to by
295-786: A distinctive approach to object orientation, classes, and such. Inheritance is not obvious in Wirth's design since his nomenclature looks in the opposite direction: It is called type extension and the viewpoint is from the parent down to the inheritor. Object-oriented features have been added to many previously existing languages, including Ada , BASIC , Fortran , Pascal , and COBOL . Adding these features to languages that were not initially designed for them often led to problems with compatibility and maintainability of code. More recently, some languages have emerged that are primarily object-oriented, but that are also compatible with procedural methodology. Two such languages are Python and Ruby . Probably
354-430: A form of polymorphism – is when calling code can be independent of which class in the supported hierarchy it is operating on – the parent class or one of its descendants. Meanwhile, the same operation name among objects in an inheritance hierarchy may behave differently. For example, objects of the type Circle and Square are derived from a common class called Shape. The Draw function for each type of Shape implements what
413-482: A fruit if the object fruit exists, and both apple and orange have fruit as their prototype. The idea of the fruit class does not exist explicitly, but can be modeled as the equivalence class of the objects sharing the same prototype, or as the set of objects satisfying a certain interface ( duck typing ). Unlike class-based programming, it is typically possible in prototype-based languages to define attributes and methods not shared with other objects; for example,
472-402: A given type or class of object. Objects are created by calling a special type of method in the class known as a constructor . Classes may inherit from other classes, so they are arranged in a hierarchy that represents "is-a-type-of" relationships. For example, class Employee might inherit from class Person. All the data and methods available to the parent class also appear in the child class with
531-485: A mixin is simply a class that does not represent an is-a-type-of relationship. Mixins are typically used to add the same methods to multiple classes. For example, class UnicodeConversionMixin might provide a method unicode_to_ascii() when included in class FileReader and class WebPageScraper, which do not share a common parent. Abstract classes cannot be instantiated into objects; they exist only for inheritance into other "concrete" classes that can be instantiated. In Java,
590-580: A network, only able to communicate with messages (so messaging came at the very beginning – it took a while to see how to do messaging in a programming language efficiently enough to be useful). Alan Kay, Influenced by the work at MIT and the Simula language, in November 1966 Alan Kay began working on ideas that would eventually be incorporated into the Smalltalk programming language. Kay used
649-457: A separate location addressed via a pointer). Date and Darwen have proposed a theoretical foundation that uses OOP as a kind of customizable type system to support RDBMS , but it forbids object pointers. The OOP paradigm has been criticized for overemphasizing the use of objects for software design and modeling at the expense of other important aspects (computation/algorithms). For example, Rob Pike has said that OOP languages frequently shift
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#1732772533460708-421: A special name such as this or self used to refer to the current object. In languages that support open recursion , object methods can call other methods on the same object (including themselves) using this name. This variable is late-bound ; it allows a method defined in one class to invoke another method that is defined later, in some subclass thereof. Simula (1967) is generally accepted as being
767-437: A strangely skewed perspective. Rich Hickey , creator of Clojure , described object systems as overly simplistic models of the real world. He emphasized the inability of OOP to model time properly, which is getting increasingly problematic as software systems become more concurrent. Alexander Stepanov compares object orientation unfavourably to generic programming : I find OOP technically unsound. It attempts to decompose
826-448: Is delegated to its parent object or class, and so on, going up the chain of inheritance. Data abstraction is a design pattern in which data are visible only to semantically related functions, to prevent misuse. The success of data abstraction leads to frequent incorporation of data hiding as a design principle in object-oriented and pure functional programming. Similarly, encapsulation prevents external code from being concerned with
885-493: Is a technique that encourages decoupling . In object oriented programming, objects provide a layer which can be used to separate internal from external code and implement abstraction and encapsulation. External code can only use an object by calling a specific instance method with a certain set of input parameters, reading an instance variable, or writing to an instance variable. A program may create many instances of objects as it runs, which operate independently. This technique, it
944-403: Is also a form of information hiding. Some languages (Java, for example) let classes enforce access restrictions explicitly, for example, denoting internal data with the private keyword and designating methods intended for use by code outside the class with the public keyword. Methods may also be designed public, private, or intermediate levels such as protected (which allows access from
1003-405: Is called (i.e. at least one other parameter object is involved in the method choice), one speaks of multiple dispatch . A method call is also known as message passing . It is conceptualized as a message (the name of the method and its input parameters) being passed to the object for dispatch. Dispatch interacts with inheritance; if a method is not present in a given object or class, the dispatch
1062-516: Is claimed, allows easy re-use of the same procedures and data definitions for different sets of data, in addition to potentially mirroring real-world relationships intuitively. Rather than utilizing database tables and programming subroutines, the developer utilizes objects the user may be more familiar with: objects from their application domain. These claims that the OOP paradigm enhances reusability and modularity have been criticized. The initial design
1121-486: Is different from Wikidata All article disambiguation pages All disambiguation pages oop (Redirected from Oop ) [REDACTED] Look up oop or OOP in Wiktionary, the free dictionary. OOP , Oop , or oop may refer to: Science and technology [ edit ] Object-oriented positioning , another name for feature-oriented positioning in microscopy Object-oriented programming ,
1180-533: Is different from Wikidata All article disambiguation pages All disambiguation pages Object-oriented programming Object-oriented programming ( OOP ) is a programming paradigm based on the concept of objects , which can contain data and code : data in the form of fields (often known as attributes or properties ), and code in the form of procedures (often known as methods ). In OOP, computer programs are designed by making them out of objects that interact with one another. Many of
1239-520: Is difficult because of lack of an agreed-upon and rigorous definition of OOP. Modular programming support provides the ability to group procedures into files and modules for organizational purposes. Modules are namespaced so identifiers in one module will not conflict with a procedure or variable sharing the same name in another file or module. An object is a data structure or abstract data type containing fields (state variables containing data) and methods ( subroutines or procedures defining
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#17327725334601298-429: Is encouraged to use the most restrictive visibility possible, in order of local (or method) variables, private variables (in object oriented programming), and global (or public) variables, and only be expanded when and as much as necessary. This prevents changes to visibility from invalidating existing code. If a class does not allow calling code to access internal object data and permits access through methods only, this
1357-564: Is known as object composition . For example, an object in the Employee class might contain (either directly or through a pointer) an object in the Address class, in addition to its own instance variables like "first_name" and "position". Object composition is used to represent "has-a" relationships: every employee has an address, so every Employee object has access to a place to store an Address object (either directly embedded within itself or at
1416-408: Is necessary to draw itself while calling code can remain indifferent to the particular type of Shape being drawn. This is another type of abstraction that simplifies code external to the class hierarchy and enables strong separation of concerns . A common feature of objects is that methods are attached to them and can access and modify the object's data fields. In this brand of OOP, there is usually
1475-450: Is quoted as saying: The problem with object-oriented languages is they've got all this implicit environment that they carry around with them. You wanted a banana but what you got was a gorilla holding the banana and the entire jungle. Leo Brodie has suggested a connection between the standalone nature of objects and a tendency to duplicate code in violation of the don't repeat yourself principle of software development. Subtyping –
1534-635: The final keyword can be used to prevent a class from being subclassed. In contrast, in prototype-based programming , objects are the primary entities. Generally, the concept of a "class" does not even exist. Rather, the prototype or parent of an object is just another object to which the object is linked. In Self, an object may have multiple or no parents, but in the most popular prototype-based language, Javascript, every object has one prototype link (and only one). New objects can be created based on already existing objects chosen as their prototype. You may call two different objects apple and orange
1593-427: The C programming language . The " open/closed principle " advocates that classes and functions "should be open for extension, but closed for modification". Luca Cardelli has claimed that OOP languages have "extremely poor modularity properties with respect to class extension and modification", and tend to be extremely complex. The latter point is reiterated by Joe Armstrong , the principal inventor of Erlang , who
1652-583: The Cocoa frameworks on Mac OS X , written in Objective-C , an object-oriented, dynamic messaging extension to C based on Smalltalk. OOP toolkits also enhanced the popularity of event-driven programming (although this concept is not limited to OOP). At ETH Zürich , Niklaus Wirth and his colleagues investigated the concept of type checking across module boundaries. Modula-2 (1978) included this concept, and their succeeding design, Oberon (1987), included
1711-541: The Linn Smart Rekursiv . In the mid-1980s Objective-C was developed by Brad Cox , who had used Smalltalk at ITT Inc. . Bjarne Stroustrup , who had used Simula for his PhD thesis, created the object-oriented C++ . In 1985, Bertrand Meyer also produced the first design of the Eiffel language . Focused on software quality, Eiffel is a purely object-oriented programming language and a notation supporting
1770-460: The 1970s, the first version of the Smalltalk programming language was developed at Xerox PARC by Alan Kay , Dan Ingalls and Adele Goldberg . Smalltalk-72 included a programming environment and was dynamically typed , and at first was interpreted , not compiled . Smalltalk became noted for its application of object orientation at the language-level and its graphical development environment. Smalltalk went through various versions and interest in
1829-522: The August issue of Byte Magazine , introducing Smalltalk and object-oriented programming to a wide audience. LOOPS, the object system for Interlisp -D, was influenced by Smalltalk and Flavors, and a paper about it was published in 1982. In 1986, the Association for Computing Machinery organized the first Conference on Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), which
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1888-553: The attribute sugar_content may be defined in apple but not orange . Some languages like Go do not support inheritance at all. Go states that it is object-oriented, and Bjarne Stroustrup, author of C++, has stated that it is possible to do OOP without inheritance. The doctrine of composition over inheritance advocates implementing has-a relationships using composition instead of inheritance. For example, instead of inheriting from class Person, class Employee could give each Employee object an internal Person object, which it then has
1947-487: The class concept covered by "master" or "definition"), albeit specialized to graphical interaction. Also, in 1968, an MIT ALGOL version, AED-0, established a direct link between data structures ("plexes", in that dialect) and procedures, prefiguring what were later termed "messages", "methods", and "member functions". Topics such as data abstraction and modular programming were common points of discussion at this time. Independently of later MIT work such as AED, Simula
2006-432: The class or the instance; this leads to the following terms: Depending on the definition of the language, subclasses may or may not be able to override the methods defined by superclasses. Multiple inheritance is allowed in some languages, though this can make resolving overrides complicated. Some languages have special support for other concepts like traits and mixins , though, in any language with multiple inheritance,
2065-415: The dominant programming paradigm when programming languages supporting the techniques became widely available. These included Visual FoxPro 3.0, C++ , and Delphi . Its dominance was further enhanced by the rising popularity of graphical user interfaces , which rely heavily upon object-oriented programming techniques. An example of a closely related dynamic GUI library and OOP language can be found in
2124-424: The emphasis on abstraction is vital. Object-oriented languages extend the notion of type to incorporate data abstraction, highlighting the significance of restricting access to internal data through methods. Eric S. Raymond has written that object-oriented programming languages tend to encourage thickly layered programs that destroy transparency. Raymond compares this unfavourably to the approach taken with Unix and
2183-589: The entire software lifecycle. Meyer described the Eiffel software development method, based on a small number of key ideas from software engineering and computer science, in Object-Oriented Software Construction . Essential to the quality focus of Eiffel is Meyer's reliability mechanism, design by contract , which is an integral part of both the method and language. In the early and mid-1990s object-oriented programming developed as
2242-525: The first language with the primary features of an object-oriented language. It was created for making simulation programs , in which what came to be called objects were the most important information representation. Smalltalk (1972 to 1980) is another early example and the one with which much of the theory of OOP was developed. Concerning the degree of object orientation, the following distinctions can be made: Many widely used languages, such as C++, Java, and Python, provide object-oriented features. Although in
2301-422: The focus from data structures and algorithms to types . Steve Yegge noted that, as opposed to functional programming : Object Oriented Programming puts the nouns first and foremost. Why would you go to such lengths to put one part of speech on a pedestal? Why should one kind of concept take precedence over another? It's not as if OOP has suddenly made verbs less important in the way we actually think. It's
2360-465: The form of either classes or prototypes . These forms of inheritance are significantly different, but analogous terminology is used to define the concepts of object and instance . In class-based programming , the most popular style, each object is required to be an instance of a particular class . The class defines the data format or type (including member variables and their types) and available procedures (class methods or member functions) for
2419-467: The internal workings of an object. This facilitates code refactoring , for example allowing the author of the class to change how objects of that class represent their data internally without changing any external code (as long as "public" method calls work the same way). It also encourages programmers to put all the code that is concerned with a certain set of data in the same class, which organizes it for easy comprehension by other programmers. Encapsulation
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2478-418: The language grew. While Smalltalk was influenced by the ideas introduced in Simula 67 it was designed to be a fully dynamic system in which classes could be created and modified dynamically. During the late 1970s and 1980s, object-oriented programming rose to prominence. The Flavors object-oriented Lisp was developed starting 1979, introducing multiple inheritance and mixins . In 1981, Goldberg edited
2537-466: The modern sense of object-oriented programming made its first appearance at the artificial intelligence group at MIT in the late 1950s and early 1960s. "Object" referred to LISP atoms with identified properties (attributes). Another early MIT example was Sketchpad created by Ivan Sutherland in 1960–1961; in the glossary of the 1963 technical report based on his dissertation about Sketchpad, Sutherland defined notions of "object" and "instance" (with
2596-448: The most commercially important recent object-oriented languages are Java , developed by Sun Microsystems , as well as C# and Visual Basic.NET (VB.NET), both designed for Microsoft's .NET platform. Each of these two frameworks shows, in its way, the benefit of using OOP by creating an abstraction from implementation. VB.NET and C# support cross-language inheritance, allowing classes defined in one language to subclass classes defined in
2655-675: The most widely used programming languages (such as C++ , Java , and Python ) are multi-paradigm and support object-oriented programming to a greater or lesser degree, typically in combination with imperative programming , procedural programming and functional programming . Significant object-oriented languages include Ada , ActionScript , C++ , Common Lisp , C# , Dart , Eiffel , Fortran 2003 , Haxe , Java , JavaScript , Kotlin , Logo , MATLAB , Objective-C , Object Pascal , Perl , PHP , Python , R , Raku , Ruby , Scala , SIMSCRIPT , Simula , Smalltalk , Swift , Vala and Visual Basic.NET . Terminology invoking "objects" in
2714-437: The object's behavior in code). Fields may also be known as members, attributes, or properties. Objects are typically stored as contiguous regions of memory . Objects are accessed somewhat like variables with complex internal structures, and in many languages are effectively pointers , serving as actual references to a single instance of said object in memory within a heap or stack. Objects sometimes correspond to things found in
2773-613: The opportunity to hide from external code even if class Person has many public attributes or methods. Delegation is another language feature that can be used as an alternative to inheritance. Rob Pike has criticized the OO mindset for preferring a multilevel type hierarchy with layered abstractions to a three-line lookup table . He has called object-oriented programming "the Roman numerals of computing". Bob Martin states that because they are software, related classes do not necessarily share
2832-477: The other language. Object-oriented programming uses objects, but not all of the associated techniques and structures are supported directly in languages that claim to support OOP. The features listed below are common among languages considered to be strongly class- and object-oriented (or multi-paradigm with OOP support), with notable exceptions mentioned. Christopher J. Date stated that critical comparison of OOP to other technologies, relational in particular,
2891-439: The past object-oriented programming was widely accepted, more recently essays criticizing object-oriented programming and recommending the avoidance of these features (generally in favor of functional programming ) have been very popular in the developer community. Paul Graham has suggested that OOP's popularity within large companies is due to "large (and frequently changing) groups of mediocre programmers". According to Graham,
2950-467: The real world. For example, a graphics program may have objects such as "circle", "square", and "menu". An online shopping system might have objects such as "shopping cart", "customer", and "product". Sometimes objects represent more abstract entities, like an object that represents an open file, or an object that provides the service of translating measurements from U.S. customary to metric. Objects can contain other objects in their instance variables; this
3009-401: The relationships of the things they represent. It is the responsibility of the object, not any external code, to select the procedural code to execute in response to a method call, typically by looking up the method at run time in a table associated with the object. This feature is known as dynamic dispatch . If the call variability relies on more than the single type of the object on which it
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#17327725334603068-448: The same class and its subclasses, but not objects of a different class). In other languages (like Python) this is enforced only by convention (for example, private methods may have names that start with an underscore ). In C#, Swift & Kotlin languages, internal keyword permits access only to files present in the same assembly, package, or module as that of the class. In programming languages, particularly object-oriented ones,
3127-403: The same names. For example, class Person might define variables "first_name" and "last_name" with method "make_full_name()". These will also be available in class Employee, which might add the variables "position" and "salary". It is guaranteed that all instances of class Employee will have the same variables, such as the name, position, and salary. Procedures and variables can be specific to either
3186-403: The same term [REDACTED] This disambiguation page lists articles associated with the title OOP . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=OOP&oldid=1211051963 " Category : Disambiguation pages Hidden categories: Short description
3245-403: The same term [REDACTED] This disambiguation page lists articles associated with the title OOP . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=OOP&oldid=1211051963 " Category : Disambiguation pages Hidden categories: Short description
3304-495: The term "object-oriented programming" in conversation as early as 1967. Although sometimes called "the father of object-oriented programming", Alan Kay has differentiated his notion of OO from the more conventional abstract data type notion of object, and has implied that the computer science establishment did not adopt his notion. A 1976 MIT memo co-authored by Barbara Liskov lists Simula 67 , CLU , and Alphard as object-oriented languages, but does not mention Smalltalk. In
3363-480: The world in terms of interfaces that vary on a single type. To deal with the real problems you need multisorted algebras — families of interfaces that span multiple types. I find OOP philosophically unsound. It claims that everything is an object. Even if it is true it is not very interesting — saying that everything is an object is saying nothing at all. OOP languages are diverse, but typically OOP languages allow inheritance for code reuse and extensibility in
3422-543: Was attended by 1,000 people. Among other developments was the Common Lisp Object System , which integrates functional programming and object-oriented programming and allows extension via a Meta-object protocol . In the 1980s, there were a few attempts to design processor architectures that included hardware support for objects in memory but these were not successful. Examples include the Intel iAPX 432 and
3481-506: Was developed during the years 1961–1967. Simula introduced important concepts that are today an essential part of object-oriented programming, such as class and object , inheritance, and dynamic binding . The object-oriented Simula programming language was used mainly by researchers involved with physical modelling , such as models to study and improve the movement of ships and their content through cargo ports. I thought of objects being like biological cells and/or individual computers on
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