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Connascence (computer Programming)
Connascence () is a software quality metric invented by Meilir Page-Jones to allow reasoning about the complexity caused by dependency relationships in object-oriented design much like coupling did for structured design. In software engineering, two components are connascent if a change in one would require the other to be modified in order to maintain the overall correctness of the system. In addition to allowing categorization of dependency relationships, connascence also provides a system for comparing different types of dependency. Such comparisons between potential designs can often hint at ways to improve the quality of the software. Strength A form of connascence is considered to be stronger if it is more likely to require compensating changes in connascent elements. The stronger the form of connascence, the more difficult and costly it is to change the elements in the relationship. Degree The acceptability of connascence is related to the degree of its occurrence. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Metric
In software engineering and development, a software metric is a standard of measure of a degree to which a software system or process possesses some property. Even if a metric is not a measurement (metrics are functions, while measurements are the numbers obtained by the application of metrics), often the two terms are used as synonyms. Since quantitative measurements are essential in all sciences, there is a continuous effort by computer science practitioners and theoreticians to bring similar approaches to software development. The goal is obtaining objective, reproducible and quantifiable measurements, which may have numerous valuable applications in schedule and budget planning, cost estimation, quality assurance, testing, software debugging, software performance optimization, and optimal personnel task assignments. Common software measurements Common software measurements include: * ABC Software Metric * Balanced scorecard * Bugs per line of code * Code coverage * Cohe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Object-oriented Design
Object-oriented design (OOD) is the process of planning a system of interacting objects for the purpose of solving a software problem. It is one approach to software design. Overview An object contains encapsulated data and procedures grouped together to represent an entity. The 'object interface' defines how the object can be interacted with. An object-oriented program is described by the interaction of these objects. Object-oriented design is the discipline of defining the objects and their interactions to solve a problem that was identified and documented during object-oriented analysis. What follows is a description of the class-based subset of object-oriented design, which does not include object prototype-based approaches where objects are not typically obtained by instantiating classes but by cloning other (prototype) objects. Object-oriented design is a method of design encompassing the process of object-oriented decomposition and a notation for depicting both logical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coupling (computer Programming)
In software engineering, coupling is the degree of interdependence between software modules; a measure of how closely connected two routines or modules are; the strength of the relationships between modules. Coupling is usually contrasted with cohesion. Low coupling often correlates with high cohesion, and vice versa. Low coupling is often thought to be a sign of a well-structured computer system and a good design, and when combined with high cohesion, supports the general goals of high readability and maintainability. History The software quality metrics of coupling and cohesion were invented by Larry Constantine in the late 1960s as part of a structured design, based on characteristics of “good” programming practices that reduced maintenance and modification costs. Structured design, including cohesion and coupling, were published in the article ''Stevens, Myers & Constantine'' (1974) and the book ''Yourdon & Constantine'' (1979), and the latter subsequently became stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structured Design
In software engineering, structured analysis (SA) and structured design (SD) are methods for analyzing business requirements and developing specifications for converting practices into computer programs, hardware configurations, and related manual procedures. Structured analysis and design techniques are fundamental tools of systems analysis. They developed from classical systems analysis of the 1960s and 1970s. Objectives of structured analysis Structured analysis became popular in the 1980s and is still in use today. Structured analysis consists of interpreting the system concept (or real world situations) into data and control terminology represented by data flow diagrams. The flow of data and control from bubble to the data store to bubble can be difficult to track and the number of bubbles can increase. One approach is to first define events from the outside world that require the system to react, then assign a bubble to that event. Bubbles that need to interact are then c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Engineering
Software engineering is a systematic engineering approach to software development. A software engineer is a person who applies the principles of software engineering to design, develop, maintain, test, and evaluate computer software. The term '' programmer'' is sometimes used as a synonym, but may also lack connotations of engineering education or skills. Engineering techniques are used to inform the software development process which involves the definition, implementation, assessment, measurement, management, change, and improvement of the software life cycle process itself. It heavily uses software configuration management which is about systematically controlling changes to the configuration, and maintaining the integrity and traceability of the configuration and code throughout the system life cycle. Modern processes use software versioning. History Beginning in the 1960s, software engineering was seen as its own type of engineering. Additionally, the development of soft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Components
Component-based software engineering (CBSE), also called component-based development (CBD), is a branch of software engineering that emphasizes the separation of concerns with respect to the wide-ranging functionality available throughout a given software system. It is a reuse-based approach to defining, implementing and composing loosely coupled independent components into systems. This practice aims to bring about an equally wide-ranging degree of benefits in both the short-term and the long-term for the software itself and for organizations that sponsor such software. Software engineering practitioners regard components as part of the starting platform for service-orientation. Components play this role, for example, in web services, and more recently, in service-oriented architectures (SOA), whereby a component is converted by the web service into a ''service'' and subsequently inherits further characteristics beyond that of an ordinary component. Components can produce or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locality Of Reference
In computer science, locality of reference, also known as the principle of locality, is the tendency of a processor to access the same set of memory locations repetitively over a short period of time. There are two basic types of reference locality temporal and spatial locality. Temporal locality refers to the reuse of specific data and/or resources within a relatively small time duration. Spatial locality (also termed ''data locality''"NIST Big Data Interoperability Framework: Volume 1"urn:doi:10.6028/NIST.SP.1500-1r2) refers to the use of data elements within relatively close storage locations. Sequential locality, a special case of spatial locality, occurs when data elements are arranged and accessed linearly, such as traversing the elements in a one-dimensional Array data structure, array. Locality is a type of predictability, predictable behavior that occurs in computer systems. Systems that exhibit strong ''locality of reference'' are great candidates for performance optimiza ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parameter (computer Programming)
In computer programming, a parameter or a formal argument is a special kind of variable used in a subroutine to refer to one of the pieces of data provided as input to the subroutine. These pieces of data are the values of the arguments (often called ''actual arguments'' or ''actual parameters'') with which the subroutine is going to be called/invoked. An ordered list of parameters is usually included in the definition of a subroutine, so that, each time the subroutine is called, its arguments for that call are evaluated, and the resulting values can be assigned to the corresponding parameters. Unlike ''argument'' in usual mathematical usage, the ''argument'' in computer science is the actual input expression passed/supplied to a function, procedure, or routine in the invocation/call statement, whereas the ''parameter'' is the variable inside the implementation of the subroutine. For example, if one defines the add subroutine as def add(x, y): return x + y, then x, y are paramet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Message Authentication Code
In cryptography, a message authentication code (MAC), sometimes known as a ''tag'', is a short piece of information used for authenticating a message. In other words, to confirm that the message came from the stated sender (its authenticity) and has not been changed. The MAC value protects a message's data integrity, as well as its authenticity, by allowing verifiers (who also possess the secret key) to detect any changes to the message content. Terminology The term message integrity code (MIC) is frequently substituted for the term ''MAC'', especially in communications to distinguish it from the use of the latter as ''media access control address'' (''MAC address''). However, some authors use MIC to refer to a message digest, which aims only to uniquely but opaquely identify a single message. RFC 4949 recommends avoiding the term ''message integrity code'' (MIC), and instead using ''checksum'', ''error detection code'', '' hash'', ''keyed hash'', ''message authentication code'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Named Parameters
In computer programming, named parameters, named argument or keyword arguments refer to a computer language's support for function calls that clearly state the name of each parameter within the function call. Overview A function call using named parameters differs from a regular function call in that the values are passed by associating each one with a parameter name, instead of providing an ordered list of values. For example, consider this Java or C# method call using no named parameters: window.addNewControl("Title", 20, 50, 100, 50, true); Using named parameters in Python, the call can be written as: window.addNewControl(title="Title", xPosition=20, yPosition=50, width=100, height=50, drawingNow=True) Using named parameters in PHP, the call can be written as: $window->addNewControl(title: "Title", xPosition: 20, yPosit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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