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to a device at the application level, the program calls a function to open the device, which may be a real device such as a terminal or a virtual device such as a network port or a file in a file system. The device's physical characteristics are mediated by the operating system which in turn presents an abstract interface that allows the programmer to read and write bytes from/to the device. The operating system then performs the actual transformation needed to read and write the stream of bytes to the device.
85:, away from any specific implementation. These generalizations arise from broad similarities that are best encapsulated by models that express similarities present in various specific implementations. The simplification provided by a good abstraction layer allows for easy reuse by distilling a useful concept or
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Most graphics libraries such as OpenGL provide an abstract graphical device model as an interface. The library is responsible for translating the commands provided by the programmer into the specific device commands needed to draw the graphical elements and objects. The specific device commands for a
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Programmable logic is often considered part of the hardware, while the logical definitions are also sometimes seen as part of a device's software or firmware. Firmware may include only low-level software, but can also include all software, including an operating system and applications. The software
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In the Unix operating system, most types of input and output operations are considered to be streams of bytes read from a device or written to a device. This stream of bytes model is used for file I/O, socket I/O, and terminal I/O in order to provide device independence. In order to read and write
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on it. Every layer can exist without the layers above it, and requires the layers below it to function. Frequently abstraction layers can be composed into a hierarchy of abstraction levels. The OSI model comprises seven abstraction layers. Each layer of the model encapsulates and addresses a
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layers can be further divided into hardware abstraction layers, physical and logical device drivers, repositories such as filesystems, operating system kernels, middleware, applications, and others. A distinction can also be made from low-level programming languages like
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so that situations, where it may be accurately applied, can be quickly recognized. Just composing lower-level elements into a construct doesn't count as an abstraction layer unless it shields users from its underlying complexity.
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Enterprise
Integration Patterns: Designing, Building, and Deploying Messaging Solutions (Addison-Wesley Signature Series (Fowler))
113:." This is often deliberately misquoted with "abstraction" substituted for "indirection." It is also sometimes misattributed to
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different part of the needs of digital communications, thereby reducing the complexity of the associated engineering solutions.
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is a way of hiding the working details of a subsystem. Examples of software models that use layers of abstraction include the
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is, "All problems in computer science can be solved by another level of
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336:. Sebastopol, CA: O'Reilly and Associates. pp. 279–291.
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Beautiful Code: Leading
Programmers Explain How They Think
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that are generally useful for drawing graphical objects.
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A layer is considered to be on top of another if it
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363:from the original on Mar 29, 2022 – via
27:Way of hiding details of a computing subsystem
353:"@drunkcod Yes, that's my corollary :^)"
200:are different from the device commands for a
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330:"Chapter 17. Another Level of Indirection"
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351:Henney, Kevlin (September 3, 2012).
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340:from the original on Mar 6, 2024.
221:Application programming interface
383:Structured Computer Organization
293:. Addison-Wesley Professional.
289:Hohpe, Gregor (March 9, 2012).
249:Layer (object-oriented design)
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387:Englewood Cliffs, New Jersey
328:Spinellis, Diomidis (2007).
227:Application binary interface
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60:separation of concerns
417:Computer architecture
131:computer architecture
125:Computer architecture
68:platform independence
379:Tanenbaum, Andrew S.
313:: CS1 maint: year (
270:Software engineering
239:Hardware abstraction
254:Namespace violation
18:Architectural layer
244:Information hiding
143:programmable logic
58:, which allow the
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389:: Prentice-Hall.
168:compiled language
164:assembly language
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172:interpreter
111:indirection
411:Categories
276:References
209:primitives
309:cite book
83:algorithm
44:OSI model
32:computing
381:(1979).
361:Archived
338:Archived
233:Compiler
215:See also
191:Graphics
148:hardware
138:software
365:Twitter
205:monitor
198:plotter
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315:link
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