Content deleted Content added
Stevebroshar (talk | contribs) →History: He was talking about waterfall ... even though the name wasn't coined in the 60s |
Stevebroshar (talk | contribs) Order by popularity |
||
Line 38:
Among these, another software development process has been established in [[Open-source software|open source]]. The adoption of these best practices known and established processes within the confines of a company is called [[inner source]].
==
The following are notable methodologies somewhat ordered by popularity.
[[Software prototyping]] is about creating prototypes, i.e. incomplete versions of the software program being developed.▼
The basic principles are:<ref name=CMS08/>▼
* Prototyping is not a standalone, complete development methodology, but rather an approach to try out particular features in the context of a full methodology (such as incremental, spiral, or rapid application development (RAD)).▼
* Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease of change during the development process.▼
* The client is involved throughout the development process, which increases the likelihood of client acceptance of the final implementation.▼
* While some prototypes are developed with the expectation that they will be discarded, it is possible in some cases to evolve from prototype to working system.▼
A basic understanding of the fundamental business problem is necessary to avoid solving the wrong problems, but this is true for all software methodologies.▼
=== Agile development ===
Line 81 ⟶ 70:
</ref>
[[Grady Booch]] first named and proposed CI in [[Booch method|his 1991 method]],<ref>{{cite book |last= Booch |first= Grady |author-link= Grady Booch |year= 1991 |title=Object Oriented Design: With Applications |url= https://books.google.com/books?id=w5VQAAAAMAAJ&q=continuous+integration+inauthor:grady+inauthor:booch |publisher= [[Benjamin Cummings]] |page= 209 |isbn= 9780805300918 |access-date= August 18, 2014 }}</ref> although he did not advocate integrating several times a day. [[Extreme programming]] (XP) adopted the concept of CI and did advocate integrating more than once per day – perhaps as many as tens of times per day.
=== Incremental development ===▼
{{main|Iterative and incremental development}}▼
Various methods are acceptable for combining linear and iterative systems development methodologies, with the primary objective of each being to reduce inherent project risk by breaking a project into smaller segments and providing more ease-of-change during the development process.▼
There are three main variants of incremental development:<ref name=CMS08/>▼
# A series of mini-waterfalls are performed, where all phases of the waterfall are completed for a small part of a system, before proceeding to the next increment, or▼
# Overall requirements are defined before proceeding to evolutionary, mini-waterfall development of individual increments of a system, or▼
# The initial software concept, requirements analysis, and design of architecture and system core are defined via waterfall, followed by incremental implementation, which culminates in installing the final version, a working system.▼
=== Rapid application development ===▼
{{main|Rapid application development}}▼
[[File:RADModel.JPG|thumb|Rapid Application Development (RAD) Model]]▼
[[Rapid application development]] (RAD) is a software development methodology, which favors [[iterative development]] and the rapid construction of [[prototype]]s instead of large amounts of up-front planning. The "planning" of software developed using RAD is interleaved with writing the software itself. The lack of extensive pre-planning generally allows software to be written much faster and makes it easier to change requirements.▼
The rapid development process starts with the development of preliminary [[data model]]s and [[business process model]]s using [[structured technique]]s. In the next stage, requirements are verified using prototyping, eventually to refine the data and process models. These stages are repeated iteratively; further development results in "a combined business requirements and technical design statement to be used for constructing new systems".<ref name=WBD04/>▼
The term was first used to describe a software development process introduced by [[James Martin (author)|James Martin]] in 1991. According to Whitten (2003), it is a merger of various [[Structured Analysis and Design Technique|structured techniques]], especially data-driven [[information technology engineering]], with prototyping techniques to accelerate software systems development.<ref name="WBD04">[[Whitten, Jeffrey L.]]; [[Lonnie D. Bentley]], [[Kevin C. Dittman]]. (2003). ''Systems Analysis and Design Methods''. 6th edition. {{ISBN|0-256-19906-X}}.</ref>▼
The basic principles of rapid application development are:<ref name=CMS08/>▼
* Key objective is for fast development and delivery of a high-quality system at a relatively low investment cost.▼
* Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease of change during the development process.▼
* Aims to produce high-quality systems quickly, primarily via iterative Prototyping (at any stage of development), active user involvement, and computerized development tools. These tools may include [[graphical user interface]] (GUI) builders, [[Computer Aided Software Engineering]] (CASE) tools, [[Database Management System]]s (DBMS), [[fourth-generation programming language]]s, code generators, and object-oriented techniques.▼
* Key emphasis is on fulfilling the business need, while technological or engineering excellence is of lesser importance.▼
* Project control involves prioritizing development and defining delivery deadlines or “timeboxes”. If the project starts to slip, the emphasis is on reducing requirements to fit the timebox, not on increasing the deadline.▼
* Generally includes [[joint application design]] (JAD), where users are intensely involved in [[system design]], via consensus building in either structured workshops, or electronically facilitated interaction.▼
* Active user involvement is imperative.▼
* Iteratively produces production software, as opposed to a throwaway prototype.▼
* Produces documentation necessary to facilitate future development and maintenance.▼
* Standard systems analysis and design methods can be fitted into this framework.▼
=== Waterfall development ===
Line 143 ⟶ 97:
=== Spiral development ===
[[File:Spiral model (Boehm, 1988).svg|thumb|400px|Spiral model (Boehm, 1988)]]
{{main|Spiral model}}
Line 156 ⟶ 108:
* Each trip around the spiral traverses four basic quadrants: (1) determine objectives, alternatives, and constraints of the iteration, and (2) evaluate alternatives; Identify and resolve risks; (3) develop and verify deliverables from the iteration; and (4) plan the next iteration.<ref name="RT-BB86">{{cite book |author1=Richard H. Thayer |author2=Barry W. Boehm |author2-link=Barry Boehm |date=1986 |title=Tutorial: software engineering project management |publisher=Computer Society Press of the IEEE |page=130}}</ref>
* Begin each cycle with an identification of stakeholders and their "win conditions", and end each cycle with review and commitment.<ref>{{cite book |author=Barry W. Boehm |author-link=Barry Boehm |date=2000 |title=Software cost estimation with Cocomo II: Volume 1}}</ref>
▲=== Incremental development ===
▲{{main|Iterative and incremental development}}
▲Various methods are acceptable for combining linear and iterative systems development methodologies, with the primary objective of each being to reduce inherent project risk by breaking a project into smaller segments and providing more ease-of-change during the development process.
▲There are three main variants of incremental development:<ref name=CMS08/>
▲# A series of mini-waterfalls are performed, where all phases of the waterfall are completed for a small part of a system, before proceeding to the next increment, or
▲# Overall requirements are defined before proceeding to evolutionary, mini-waterfall development of individual increments of a system, or
▲# The initial software concept, requirements analysis, and design of architecture and system core are defined via waterfall, followed by incremental implementation, which culminates in installing the final version, a working system.
=== Prototyping ===
▲[[Software prototyping]] is about creating prototypes, i.e. incomplete versions of the software program being developed.
▲The basic principles are:<ref name=CMS08/>
▲* Prototyping is not a standalone, complete development methodology, but rather an approach to try out particular features in the context of a full methodology (such as incremental, spiral, or rapid application development (RAD)).
▲* Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease of change during the development process.
▲* The client is involved throughout the development process, which increases the likelihood of client acceptance of the final implementation.
▲* While some prototypes are developed with the expectation that they will be discarded, it is possible in some cases to evolve from prototype to working system.
▲A basic understanding of the fundamental business problem is necessary to avoid solving the wrong problems, but this is true for all software methodologies.
▲=== Rapid application development ===
▲{{main|Rapid application development}}
▲[[File:RADModel.JPG|thumb|Rapid Application Development (RAD) Model]]
▲[[Rapid application development]] (RAD) is a software development methodology, which favors [[iterative development]] and the rapid construction of [[prototype]]s instead of large amounts of up-front planning. The "planning" of software developed using RAD is interleaved with writing the software itself. The lack of extensive pre-planning generally allows software to be written much faster and makes it easier to change requirements.
▲The rapid development process starts with the development of preliminary [[data model]]s and [[business process model]]s using [[structured technique]]s. In the next stage, requirements are verified using prototyping, eventually to refine the data and process models. These stages are repeated iteratively; further development results in "a combined business requirements and technical design statement to be used for constructing new systems".<ref name=WBD04/>
▲The term was first used to describe a software development process introduced by [[James Martin (author)|James Martin]] in 1991. According to Whitten (2003), it is a merger of various [[Structured Analysis and Design Technique|structured techniques]], especially data-driven [[information technology engineering]], with prototyping techniques to accelerate software systems development.<ref name="WBD04">[[Whitten, Jeffrey L.]]; [[Lonnie D. Bentley]], [[Kevin C. Dittman]]. (2003). ''Systems Analysis and Design Methods''. 6th edition. {{ISBN|0-256-19906-X}}.</ref>
▲The basic principles of rapid application development are:<ref name=CMS08/>
▲* Key objective is for fast development and delivery of a high-quality system at a relatively low investment cost.
▲* Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease of change during the development process.
▲* Aims to produce high-quality systems quickly, primarily via iterative Prototyping (at any stage of development), active user involvement, and computerized development tools. These tools may include [[graphical user interface]] (GUI) builders, [[Computer Aided Software Engineering]] (CASE) tools, [[Database Management System]]s (DBMS), [[fourth-generation programming language]]s, code generators, and object-oriented techniques.
▲* Key emphasis is on fulfilling the business need, while technological or engineering excellence is of lesser importance.
▲* Project control involves prioritizing development and defining delivery deadlines or “timeboxes”. If the project starts to slip, the emphasis is on reducing requirements to fit the timebox, not on increasing the deadline.
▲* Generally includes [[joint application design]] (JAD), where users are intensely involved in [[system design]], via consensus building in either structured workshops, or electronically facilitated interaction.
▲* Active user involvement is imperative.
▲* Iteratively produces production software, as opposed to a throwaway prototype.
▲* Produces documentation necessary to facilitate future development and maintenance.
▲* Standard systems analysis and design methods can be fitted into this framework.
=== Shape Up ===
| |||