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Identity (object-oriented Programming)
In object-oriented programming, analysis and design, object identity is the fundamental property of every object that it is distinct from other objects. Objects have identity are distinct even when they are otherwise indistinguishable, i.e. equal. In this way, object identity is closely related to the philosophical meaning. Identity and references A reference can be used to refer to an object with a specific identity. A reference contains the information that is necessary for the identity property to be realized in the programming language, and allows access to the object with the identity. A type of a target of a reference is a role. Typically, references are isomorphic to memory addresses. However, multiple such references can refer to the same object, if some form of address mapping is present ( virtual addresses / page tables / memory segments). Object identity is less useful as a semantic concept in environments or situations in which the structure of objects is not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object-oriented Programming
Object-oriented programming (OOP) is a programming paradigm based on the concept of '' objects''. Objects can contain data (called fields, attributes or properties) and have actions they can perform (called procedures or methods and implemented in code). In OOP, computer programs are designed by making them out of objects that interact with one another. Many of the most widely used programming languages (such as C++, Java, and Python) support object-oriented programming to a greater or lesser degree, typically as part of multiple paradigms in combination with others such as imperative programming and declarative 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. History The idea of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism In Object-oriented Programming
In programming language theory and type theory, polymorphism is the use of one symbol to represent multiple different types.: "Polymorphic types are types whose operations are applicable to values of more than one type." In object-oriented programming, polymorphism is the provision of one interface to entities of different data types. The concept is borrowed from a principle in biology where an organism or species can have many different forms or stages. The most commonly recognized major forms of polymorphism are: * '' Ad hoc polymorphism'': defines a common interface for an arbitrary set of individually specified types. * ''Parametric polymorphism'': not specifying concrete types and instead use abstract symbols that can substitute for any type. * ''Subtyping'' (also called ''subtype polymorphism'' or ''inclusion polymorphism''): when a name denotes instances of many different classes related by some common superclass. History Interest in polymorphic type systems developed s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Association (object-oriented Programming)
In object-oriented programming, association defines a relationship between classes of objects that allows one object instance to cause another to perform an action on its behalf. This relationship is structural, because it specifies that objects of one kind are connected to objects of another and does not represent behaviour. In generic terms, the causation is usually called "sending a message", "invoking a method" or "calling a member function" to the controlled object. Concrete implementation usually requires the requesting object to invoke a ''method'' or ''member function'' using a reference or pointer to the memory location of the controlled object. The objects that are related via the association are considered to act in a role A role (also rôle or social role) is a set of connected behaviors, rights, obligations, beliefs, and norms as conceptualized by people in a social situation. It is an expected or free or continuously changing behavior and may have a given i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Role (object-oriented Programming)
A role (also rôle or social role) is a set of connected behaviors, rights, obligations, beliefs, and norms as conceptualized by people in a social situation. It is an expected or free or continuously changing behavior and may have a given individual social status or social position. It is vital to both functionalist and interactionist understandings of society. Social role theory posits the following about social behavior: # The division of labour in society takes the form of the interaction among heterogeneous specialized positions, we call roles. # Social roles included appropriate and permitted forms of behavior and actions that recur in a group, guided by social norms, which are commonly known and hence determine the expectations for appropriate behavior in these roles, which further explains the position of a person in the society. # Roles are occupied by individuals, who are called actors. #When individuals approve of a social role (i.e., they consider the role legit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Class (computer Science)
In object-oriented programming, a class defines the shared aspects of objects created from the class. The capabilities of a class differ between programming languages, but generally the shared aspects consist of state ( variables) and behavior ( methods) that are each either associated with a particular object or with all objects of that class. Object state can differ between each instance of the class whereas the class state is shared by all of them. The object methods include access to the object state (via an implicit or explicit parameter that references the object) whereas class methods do not. If the language supports inheritance, a class can be defined based on another class with all of its state and behavior plus additional state and behavior that further specializes the class. The specialized class is a ''sub-class'', and the class it is based on is its ''superclass''. Attributes Object lifecycle As an instance of a class, an object is constructed from a class via '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instance (computer Science)
In computer science, an instance is an occurrence of a software element that is based on a type definition. When created, an occurrence is said to have been ''instantiated'', and both the creation process and the result of creation are called ''instantiation''. Examples ; Class instance: An object-oriented programming (OOP) object created from a class. Each instance of a class shares a data layout but has its own memory allocation. ; Computer instance: An occurrence of a virtual machine which typically includes storage, a virtual CPU. ; Polygonal model: In computer graphics, it can be instantiated in order to be drawn several times in different locations in a scene which can improve the performance of rendering since a portion of the work needed to display each instance is reused. ; Program instance: In a POSIX-oriented operating system, it refers to an executing process A process is a series or set of activities that interact to produce a result; it may occur once-only o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Application Programming Interface
An application programming interface (API) is a connection between computers or between computer programs. It is a type of software Interface (computing), interface, offering a service to other pieces of software. A document or standard that describes how to build such a connection or interface is called an ''API specification''. A computer system that meets this standard is said to ''implement'' or ''expose'' an API. The term API may refer either to the specification or to the implementation. In contrast to a user interface, which connects a computer to a person, an application programming interface connects computers or pieces of software to each other. It is not intended to be used directly by a person (the end user) other than a computer programmer who is incorporating it into software. An API is often made up of different parts which act as tools or services that are available to the programmer. A program or a programmer that uses one of these parts is said to ''call'' that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Application Domain
An application domain is a mechanism (similar to a process in an operating system) used within the Common Language Infrastructure (CLI) to isolate executed software applications from one another so that they do not affect each other. Each application domain has its own virtual address space which scopes the resources for the application domain using that address space In computing, an address space defines a range of discrete addresses, each of which may correspond to a network host, peripheral device, disk sector, a memory cell or other logical or physical entity. For software programs to save and retrieve .... Creating multiple application domains in the same process is not possible in .NET Core and .NET 5+. Properties A CLI application domain is contained within an operating system process. A process may contain many application domains. Application domains have isolation properties similar to that of operating system processes: * Multiple threads can exist within a sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Client (computing)
is a computer that gets information from another computer called server in the context of client–server model of computer networks. The server is often (but not always) on another computer system, in which case the client accesses the service by way of a network. A client is a program that, as part of its operation, relies on sending a request to another program or a computer hardware or software that accesses a service made available by a server (which may or may not be located on another computer). For example, web browsers are clients that connect to web servers and retrieve web pages for display. Email clients retrieve email from mail servers. Online chat uses a variety of clients, which vary on the chat protocol being used. Multiplayer video games or online video games may run as a client on each computer. The term "client" may also be applied to computers or devices that run the client software or users that use the client software. A client is part of a cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ontology (information Science)
In information science, an ontology encompasses a representation, formal naming, and definitions of the categories, properties, and relations between the concepts, data, or entities that pertain to one, many, or all domains of discourse. More simply, an ontology is a way of showing the properties of a subject area and how they are related, by defining a set of terms and relational expressions that represent the entities in that subject area. The field which studies ontologies so conceived is sometimes referred to as ''applied ontology''. Every academic discipline or field, in creating its terminology, thereby lays the groundwork for an ontology. Each uses ontological assumptions to frame explicit theories, research and applications. Improved ontologies may improve problem solving within that domain, interoperability of data systems, and discoverability of data. Translating research papers within every field is a problem made easier when experts from different countries mainta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Box (systems)
In science, computing, and engineering, a black box is a system which can be viewed in terms of its inputs and outputs (or Transfer function, transfer characteristics), without any knowledge of its internal workings. Its implementation is "opaque" (black). The term can be used to refer to many inner workings, such as those of a transistor, an engine, an algorithm, the human brain, or an institution or government. To analyze an open system (systems theory), open system with a typical "black box approach", only the behavior of the stimulus/response will be accounted for, to infer the (unknown) ''box''. The usual representation of this "black box system" is a data flow diagram centered in the box. The opposite of a black box is a system where the inner components or logic are available for inspection, which is most commonly referred to as a white box (software engineering), white box (sometimes also known as a "clear box" or a "glass box"). History The modern meaning of the term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object-oriented Analysis And Design
Object-oriented analysis and design (OOAD) is a technical approach for analyzing and designing an application, system, or business by applying object-oriented programming, as well as using visual modeling throughout the software development process to guide stakeholder communication and product quality. OOAD in modern software engineering is typically conducted in an iterative and incremental way. The outputs of OOAD activities are analysis models (for OOA) and design models (for OOD) respectively. The intention is for these to be continuously refined and evolved, driven by key factors like risks and business value. History In the early days of object-oriented technology before the mid-1990s, there were many different competing methodologies for software development and object-oriented modeling, often tied to specific Computer Aided Software Engineering (CASE) tool vendors. No standard notations, consistent terms and process guides were the major concerns at the time, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
