Unified Modeling Language UML<\/p>\n
The\u00a0Unified Modeling Language<\/b>\u00a0(UML<\/b>) is a general-purpose, developmental,\u00a0modeling language<\/a> in\u00a0software engineering<\/a>\u00a0that is intended to provide a standard way to visualize the design of a system.<\/sup><\/p>\n The creation of UML was originally motivated by the desire to standardize disparate notational systems and approaches to software design. It was developed at Rational Software<\/a>\u00a0in 1994\u20131995, with further development led by them through 1996.<\/sup><\/p>\n In 1997, UML was adopted as a standard by the\u00a0Object Management Group<\/a>\u00a0(OMG), and has been managed by this organization ever since. In 2005, UML was also published by the\u00a0International Organization for Standardization<\/a> (ISO) as an approved ISO standard.\u00a0<\/sup>Since then the standard has been periodically revised to cover the latest revision of UML.<\/sup>\u00a0In software engineering, most practitioners do not use UML, but instead produce informal hand drawn diagrams; these diagrams, however, often include elements from UML.<\/sup><\/p>\n <\/p>\n UML has been evolving since the second half of the 1990s and has its roots in the\u00a0object-oriented programming<\/a>\u00a0methods developed in the late 1980s and early 1990s. The timeline (see image) shows the highlights of the history of object-oriented modeling methods and notation.<\/p>\n It is originally based on the notations of the\u00a0Booch method<\/a>, the\u00a0object-modeling technique<\/a>\u00a0(OMT) and\u00a0object-oriented software engineering<\/a>\u00a0(OOSE), which it has integrated into a single language.<\/sup><\/p>\n Rational Software Corporation<\/a>\u00a0hired\u00a0James Rumbaugh<\/a>\u00a0from\u00a0General Electric<\/a> in 1994 and after that the company became the source for two of the most popular object-oriented modeling approaches of the day:\u00a0<\/sup>Rumbaugh’s\u00a0object-modeling technique<\/a>\u00a0(OMT) and\u00a0Grady Booch<\/a>‘s method. They were soon assisted in their efforts by\u00a0Ivar Jacobson<\/a>, the creator of the\u00a0object-oriented software engineering<\/a>\u00a0(OOSE) method, who joined them at Rational in 1995.<\/p>\n Under the technical leadership of those three (Rumbaugh, Jacobson and Booch), a consortium called the\u00a0UML Partners<\/a>\u00a0was organized in 1996 to complete the\u00a0Unified Modeling Language (UML)<\/i>\u00a0specification, and propose it to the Object Management Group (OMG) for standardization. The partnership also contained additional interested parties (for example\u00a0HP<\/a>,\u00a0DEC<\/a>,\u00a0IBM<\/a>\u00a0and\u00a0Microsoft<\/a>). The UML Partners’ UML 1.0 draft was proposed to the OMG in January 1997 by the consortium. During the same month the UML Partners formed a group, designed to define the exact meaning of language constructs, chaired by\u00a0Cris Kobryn<\/a> and administered by Ed Eykholt, to finalize the specification and integrate it with other standardization efforts. The result of this work, UML 1.1, was submitted to the OMG in August 1997 and adopted by the OMG in November 1997.<\/sup><\/p>\n After the first release a task force was formed to improve the language, which released several minor revisions, 1.3, 1.4, and 1.5.<\/p>\n The standards it produced (as well as the original standard) have been noted as being ambiguous and inconsistent.<\/sup><\/p>\n As with database Chen, Bachman, and ISO\u00a0ER diagrams<\/a>, class models are specified to use “look-across”\u00a0cardinalities<\/a>, even though several authors (Merise<\/a>,<\/sup> Elmasri & Navathe\u00a0amongst others<\/sup>) prefer same-side or “look-here” for roles and both minimum and maximum cardinalities. Recent researchers (Feinerer,<\/sup> Dullea et al.<\/sup>) have shown that the “look-across” technique used by UML and ER diagrams is less effective and less coherent when applied to\u00a0n<\/i>-ary relationships of order strictly greater than 2.<\/p>\n Feinerer says: “Problems arise if we operate under the look-across semantics as used for UML associations. Hartmann\u00a0investigates this situation and shows how and why different transformations fail.”, and: “As we will see on the next few pages, the look-across interpretation introduces several difficulties which prevent the extension of simple mechanisms from binary to\u00a0n<\/i>-ary associations.”<\/p>\n UML 2.0 major revision replaced version 1.5 in 2005, which was developed with an enlarged consortium to improve the language further to reflect new experience on usage of its features.<\/p>\n Although UML 2.1 was never released as a formal specification, versions 2.1.1 and 2.1.2 appeared in 2007, followed by UML 2.2 in February 2009. UML 2.3 was formally released in May 2010. UML 2.4.1 was formally released in August 2011.\u00a0UML 2.5 was released in October 2012 as an “In progress” version and was officially released in June 2015. Formal version 2.5.1 was adopted in December 2017.<\/p>\n There are four parts to the UML 2.x specification:<\/p>\n Until UML 2.4.1, the latest versions of these standards were:<\/p>\n Since version 2.5, the UML Specification has been simplified (without Superstructure and Infrastructure), and the latest versions of these standards are now:[21]<\/a><\/sup><\/p>\n It continues to be updated and improved by the revision task force, which resolves any issues with the language.<\/p>\n","protected":false},"excerpt":{"rendered":"Before UML 1.0<\/span><\/h3>\n
UML 1.x<\/span><\/h3>\n
Cardinality notation<\/span><\/h4>\n
UML 2<\/span><\/h3>\n
\n
\n
\n