Instance Variable
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Instance Variable
In class-based, object-oriented programming, an instance variable is a variable defined in a class (i.e. a member variable), for which each instantiated object of the class has a separate copy, or instance. An instance variable has similarities with a class variable, but is non-static. An instance variable is a variable which is declared in a class but outside of constructors, methods, or blocks. Instance variables are created when an object is instantiated, and are accessible to all the constructors, methods, or blocks in the class. Access modifiers can be given to the instance variable. An instance variable is not a class variable although there are similarities. It is a type of class attribute (or class property, field, or data member). The same dichotomy between ''instance'' and ''class'' members applies to methods ("member functions") as well; a class may have both instance methods and class method A method in object-oriented programming (OOP) is a procedure assoc ...
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Class-based
Class-based programming, or more commonly class-orientation, is a style of object-oriented programming (OOP) in which inheritance (object-oriented programming), inheritance occurs via defining ''class (computer programming), classes'' of object (computer science), objects, instead of inheritance occurring via the objects alone (compare prototype-based programming). The most popular and developed model of OOP is a class-based model, instead of an object-based model. In this model, objects are entities that combine ''state (computer science), state'' (i.e., data), ''behavior'' (i.e., procedures, or ''method (computer science), methods'') and ''identity (object-oriented programming), identity'' (unique existence among all other objects). The structure and behavior of an object are defined by a class (object-oriented programming), class, which is a definition, or blueprint, of all objects of a specific type. An object must be explicitly created based on a class and an object thus cre ...
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Block (programming)
In computer programming, a block or code block or block of code is a lexical structure of source code which is grouped together. Blocks consist of one or more Declaration (computer programming), declarations and Statement (computer science), statements. A programming language that permits the creation of blocks, including blocks Nesting (computing), nested within other blocks, is called a block-structured programming language. Blocks are fundamental to structured programming, where control structures are formed from blocks. Blocks have two functions: to group statements so that they can be treated as one statement, and to define scope (computer science), scopes for name binding, names to distinguish them from the same name used elsewhere. In a block-structured programming language, the objects named in outer blocks are visible inside inner blocks, unless they are Name masking, masked by an Object (computer science), object declared with the same name. History Ideas of block st ...
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Increment Operator
Increment or incremental may refer to: * Incrementalism, a theory (also used in politics as a synonym for gradualism) * Increment and decrement operators, the operators ++ and -- in computer programming * Incremental computing * Incremental backup, which contain only that portion that has changed since the preceding backup copy. *Increment, chess term for additional time a chess player receives on each move *Incremental game Incremental games, also known as clicker games, clicking games (on PCs) or tap games (in mobile games), are video games whose gameplay consists of the player performing simple actions such as clicking on the screen repeatedly. This "grinding" ear ...s * Increment in rounding See also * * * 1+1 (other) {{Disambiguation da:Inkrementel fr:Incrémentation nl:Increment ja:インクリメント pl:Inkrementacja ru:Инкремент sr:Инкремент sv:++ ...
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Object Lifetime
In object-oriented programming (OOP), the object lifetime (or life cycle) of an object is the time between an object's creation and its destruction. Rules for object lifetime vary significantly between languages, in some cases between implementations of a given language, and lifetime of a particular object may vary from one run of the program to another. In some cases, object lifetime coincides with variable lifetime of a variable with that object as value (both for static variables and automatic variables), but in general, object lifetime is not tied to the lifetime of any one variable. In many cases – and by default in many object-oriented languages, particularly those that use garbage collection (GC) – objects are allocated on the heap, and object lifetime is not determined by the lifetime of a given variable: the value of a variable holding an object actually corresponds to a ''reference'' to the object, not the object itself, and destruction of the variable just destr ...
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Class Method
A method in object-oriented programming (OOP) is a procedure associated with a message and an object. An object consists of ''state data'' and ''behavior''; these compose an ''interface'', which specifies how the object may be utilized by any of its various consumers. A method is a behavior of an object parametrized by a consumer. Data is represented as properties of the object, and behaviors are represented as methods. For example, a Window object could have methods such as open and close, while its state (whether it is open or closed at any given point in time) would be a property. In class-based programming, methods are defined within a class, and objects are instances of a given class. One of the most important capabilities that a method provides is ''method overriding'' - the same name (e.g., area) can be used for multiple different kinds of classes. This allows the sending objects to invoke behaviors and to delegate the implementation of those behaviors to the receiving ...
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Instance Method
A method in object-oriented programming (OOP) is a procedure associated with a message and an object. An object consists of ''state data'' and ''behavior''; these compose an ''interface'', which specifies how the object may be utilized by any of its various consumers. A method is a behavior of an object parametrized by a consumer. Data is represented as properties of the object, and behaviors are represented as methods. For example, a Window object could have methods such as open and close, while its state (whether it is open or closed at any given point in time) would be a property. In class-based programming, methods are defined within a class, and objects are instances of a given class. One of the most important capabilities that a method provides is ''method overriding'' - the same name (e.g., area) can be used for multiple different kinds of classes. This allows the sending objects to invoke behaviors and to delegate the implementation of those behaviors to the receiving ...
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Field (computer Science)
In computer science, data that has several parts, known as a '' record,'' can be divided into fields (data fields). Relational databases arrange data as sets of database records, so called rows. Each record consists of several ''fields''; the fields of all records form the columns. Examples of fields: name, gender, hair colour. In object-oriented programming, a ''field'' (also called ''data member'' or '' member variable'') is a particular piece of data encapsulated within a class or object. In the case of a regular field (also called ''instance variable''), for each instance of the object there is an instance variable: for example, an Employee class has a Name field and there is one distinct name per employee. A static field (also called ''class variable'') is one variable, which is shared by all instances. Fields are abstracted by properties, which allow them to be read and written as if they were fields, but these can be translated to getter and setter method calls. Fi ...
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Class (computer Science)
In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state (member variables) and implementations of behavior (member functions or methods). In many languages, the class name is used as the name for the class (the template itself), the name for the default constructor of the class (a subroutine that creates objects), and as the type of objects generated by instantiating the class; these distinct concepts are easily conflated. Although, to the point of conflation, one could argue that is a feature inherent in a language because of its polymorphic nature and why these languages are so powerful, dynamic and adaptable for use compared to languages without polymorphism present. Thus they can model dynamic systems (i.e. the real world, machine learning, AI) more easily. When an object is created by a constructor of the class, the resulting object is called an instance of the class, and the member variable ...
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Access Modifiers
Access modifiers (or access specifiers) are keywords in object-oriented languages that set the accessibility of classes, methods, and other members. Access modifiers are a specific part of programming language syntax used to facilitate the encapsulation of components. In C++, there are only three access modifiers. C# extends the number of them to six, while Java has four access modifiers, but three keywords for this purpose. In Java, having no keyword before defaults to the package-private modifier. When the class is declared as public, it is accessible to other classes defined in the same package as well as those defined in other packages. This is the most commonly used specifier for classes. However, a class itself cannot be declared as private. If no access specifier is stated, the default access restrictions will be applied. The class will be accessible to other classes in the same package but will be inaccessible to classes outside the package. When we say that a class i ...
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Method (computer Programming)
A method in object-oriented programming (OOP) is a procedure associated with a message and an object. An object consists of ''state data'' and ''behavior''; these compose an ''interface'', which specifies how the object may be utilized by any of its various consumers. A method is a behavior of an object parametrized by a consumer. Data is represented as properties of the object, and behaviors are represented as methods. For example, a Window object could have methods such as open and close, while its state (whether it is open or closed at any given point in time) would be a property. In class-based programming, methods are defined within a class, and objects are instances of a given class. One of the most important capabilities that a method provides is ''method overriding'' - the same name (e.g., area) can be used for multiple different kinds of classes. This allows the sending objects to invoke behaviors and to delegate the implementation of those behaviors to the receiving o ...
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Object-oriented Programming
Object-oriented programming (OOP) is a programming paradigm based on the concept of "objects", which can contain data and code. The data is in the form of fields (often known as attributes or ''properties''), and the code is in the form of procedures (often known as ''methods''). A common feature of objects is that procedures (or methods) are attached to them and can access and modify the object's data fields. In this brand of OOP, there is usually a special name such as or used to refer to the current object. In OOP, computer programs are designed by making them out of objects that interact with one another. OOP languages are diverse, but the most popular ones are class-based, meaning that objects are instances of classes, which also determine their types. Many of the most widely used programming languages (such as C++, Java, Python, etc.) are multi-paradigm and they support object-oriented programming to a greater or lesser degree, typically in combination with ...
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Constructor (object-oriented Programming)
In class-based, object-oriented programming, a constructor (abbreviation: ctor) is a special type of subroutine called to create an object. It prepares the new object for use, often accepting arguments that the constructor uses to set required member variables. A constructor resembles an instance method, but it differs from a method in that it has no explicit return type, it is not implicitly inherited and it usually has different rules for scope modifiers. Constructors often have the same name as the declaring class. They have the task of initializing the object's data members and of establishing the invariant of the class, failing if the invariant is invalid. A properly written constructor leaves the resulting object in a ''valid'' state. Immutable objects must be initialized in a constructor. Most languages allow overloading the constructor in that there can be more than one constructor for a class, with differing parameters. Some languages take consideration of some ...
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