Aspect-oriented Programming
In computing, aspect-oriented programming (AOP) is a programming paradigm that aims to increase modularity by allowing the separation of cross-cutting concerns. It does so by adding behavior to existing code (an advice) ''without'' modifying the code, instead separately specifying which code is modified via a " pointcut" specification, such as "log all function calls when the function's name begins with 'set. This allows behaviors that are not central to the business logic (such as logging) to be added to a program without cluttering the code of core functions. AOP includes programming methods and tools that support the modularization of concerns at the level of the source code, while aspect-oriented software development refers to a whole engineering discipline. Aspect-oriented programming entails breaking down program logic into cohesive areas of functionality (so-called ''concerns''). Nearly all programming paradigms support some level of grouping and encapsulation of conce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Computing
Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and software. Computing has scientific, engineering, mathematical, technological, and social aspects. Major computing disciplines include computer engineering, computer science, cybersecurity, data science, information systems, information technology, and software engineering. The term ''computing'' is also synonymous with counting and calculation, calculating. In earlier times, it was used in reference to the action performed by Mechanical computer, mechanical computing machines, and before that, to Computer (occupation), human computers. History The history of computing is longer than the history of computing hardware and includes the history of methods intended for pen and paper (or for chalk and slate) with or without the aid of tables. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metaobject
In computer science, a metaobject is an object that manipulates, creates, describes, or implements objects (including itself). The object that the metaobject pertains to is called the base object. Some information that a metaobject might define includes the base object's type, interface, class, methods, attributes, parse tree, etc. Metaobjects are examples of the computer science concept of reflection, where a system has access (usually at run time) to its own internal structure. Reflection enables a system to essentially rewrite itself on the fly, to alter its own implementation as it executes. Metaobject protocol A metaobject protocol (MOP) provides the vocabulary ( protocol) to access and manipulate the structure and behaviour of systems of objects. Typical functions of a metaobject protocol include: *Create or delete a new class *Create a new property or method *Cause a class to inherit from a different class ("change the class structure") *Generate or change the code defi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Extension Method
In object-oriented computer programming, an extension method is a method added to an object after the original object was compiled. The modified object is often a class, a prototype, or a type. Extension methods are features of some object-oriented programming languages. There is no syntactic difference between calling an extension method and calling a method declared in the type definition. Not all languages implement extension methods in an equally safe manner, however. For instance, languages such as C#, Java (viManifold d > 3).Select(d => Math.Sin(d / 2)).Sum()); // Output: // 1 Centralize common behavior However, extension methods allow features to be implemented once in ways that enable reuse without the need for inheritance or the overhead of virtual method invocations, or to require implementors of an interface to implement either trivial or woefully complex functionality. A particularly useful scenario is if the feature operates on an interface for which there i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Boolean Expression
In computer science, a Boolean expression (also known as logical expression) is an expression used in programming languages that produces a Boolean value when evaluated. A Boolean value is either true or false. A Boolean expression may be composed of a combination of the Boolean constants True/False or Yes/No, Boolean-typed variables, Boolean-valued operators, and Boolean-valued functions. Boolean expressions correspond to propositional formulas in logic and are associated to Boolean circuits. Boolean operators Most programming languages have the Boolean operators OR, AND and NOT; in C and some languages inspired by it, these are represented by ", , " (double pipe character), "&&" (double ampersand) and "!" ( exclamation point) respectively, while the corresponding bitwise operations are represented by ", ", "&" and "~" (tilde).E.g. for Java see . In the mathematical literature the symbols used are often "+" ( plus), "·" ( dot) and overbar, or "∨" ( vel), "∧" ( et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Unified Modeling Language
The Unified Modeling Language (UML) is a general-purpose visual modeling language that is intended to provide a standard way to visualize the design of a system. UML provides a standard notation for many types of diagrams which can be roughly divided into three main groups: behavior diagrams, interaction diagrams, and structure diagrams. The creation of UML was originally motivated by the desire to standardize the disparate notational systems and approaches to software design. It was developed at Rational Software in 1994–1995, with further development led by them through 1996. In 1997, UML was adopted as a standard by the Object Management Group (OMG) and has been managed by this organization ever since. In 2005, UML was also published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) as the ISO/IEC 19501 standard. Since then the standard has been periodically revised to cover the latest revision of UML. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advice In Aspect-oriented Programming
In aspect and functional programming, advice describes a class of functions which modify other functions when the latter are run; it is a certain function, method or procedure that is to be applied at a given join point of a program. Use The practical use of advice functions is generally to modify or otherwise extend the behavior of functions which cannot or should not be readily modified or extended. For instance, the Emacspeak Emacs-addon makes extensive use of advice: it must modify thousands of existing Emacs modules and functions such that it can produce audio output for the blind corresponding to the visual presentation, but it would be infeasible to copy all of them and redefine them to produce audio output in addition to their normal outputs; so, the Emacspeak programmers define advice functions which run before and after. For a simple Emacs example: suppose after a user corrected a mis-spelled word using the Emacs ispell module, they wanted to re-spellcheck the entire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Database Transaction
A database transaction symbolizes a unit of work, performed within a database management system (or similar system) against a database, that is treated in a coherent and reliable way independent of other transactions. A transaction generally represents any change in a database. Transactions in a database environment have two main purposes: # To provide reliable units of work that allow correct recovery from failures and keep a database consistent even in cases of system failure. For example: when execution prematurely and unexpectedly stops (completely or partially) in which case many operations upon a database remain uncompleted, with unclear status. # To provide isolation between programs accessing a database concurrently. If this isolation is not provided, the programs' outcomes are possibly erroneous. In a database management system, a transaction is a single unit of logic or work, sometimes made up of multiple operations. Any logical calculation done in a consistent mode in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Java (programming Language)
Java is a High-level programming language, high-level, General-purpose programming language, general-purpose, Memory safety, memory-safe, object-oriented programming, object-oriented programming language. It is intended to let programmers ''write once, run anywhere'' (Write once, run anywhere, WORA), meaning that compiler, compiled Java code can run on all platforms that support Java without the need to recompile. Java applications are typically compiled to Java bytecode, bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. The syntax (programming languages), syntax of Java is similar to C (programming language), C and C++, but has fewer low-level programming language, low-level facilities than either of them. The Java runtime provides dynamic capabilities (such as Reflective programming, reflection and runtime code modification) that are typically not available in traditional compiled languages. Java gained popularity sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterprise JavaBeans
Jakarta Enterprise Beans (EJB; formerly Enterprise JavaBeans) is one of several Java APIs for modular construction of enterprise software. EJB is a server-side software component that encapsulates business logic of an application. An EJB web container provides a runtime environment for web related software components, including computer security, Java servlet lifecycle management, transaction processing, and other web services. The EJB specification is a subset of the Jakarta EE specification. Specification The EJB specification was originally developed in 1997 by IBM and later adopted by Sun Microsystems (EJB 1.0 and 1.1) in 1999 and enhanced under the Java Community Process aJSR 19(EJB 2.0)JSR 153(EJB 2.1)JSR 220(EJB 3.0)JSR 318(EJB 3.1) anJSR 345(EJB 3.2). The EJB specification provides a standard way to implement the server-side (also called " back-end") 'business' software typically found in enterprise applications (as opposed to 'front-end' user interface software ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Microsoft Transaction Server
Microsoft Transaction Server (MTS) was software that provided services to Component Object Model (COM) software components, to make it easier to create large distributed applications. The major services provided by MTS were automated transaction management, instance management (or ''just-in-time activation'') and role-based security. MTS is considered to be the first major software to implement aspect-oriented programming. MTS was first offered in the Windows NT 4.0 Option Pack. In Windows 2000, MTS was enhanced and better integrated with the operating system and COM, and was renamed COM+. COM+ added object pooling, loosely-coupled events and user-defined simple transactions (compensating resource managers) to the features of MTS. COM+ is still provided with Windows Server 2003 and Windows Server 2008, and the Microsoft .NET Framework provides a wrapper for COM+ in the EnterpriseServices namespace. The Windows Communication Foundation (WCF) provides a way of calling COM+ ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Concern Manipulation Environment
In computing, subject-oriented programming is an object-oriented software paradigm in which the state (fields) and behavior (methods) of objects are not seen as intrinsic to the objects themselves, but are provided by various subjective perceptions ("subjects") of the objects. The term and concepts were first published in September 1993 in a conference paper which was later recognized as being one of the three most influential papers to be presented at the conference between 1986 and 1996. As illustrated in that paper, an analogy is made with the contrast between the philosophical views of Plato and Kant with respect to the characteristics of "real" objects, but applied to software ones. For example, while we may all perceive a tree as having a measurable height, weight, leaf-mass, etc., from the point of view of a bird, a tree may also have measures of relative value for food or nesting purposes, or from the point of view of a tax-assessor, it may have a certain taxable value in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |