Object-modeling language

An object-modeling language is a standardized set of symbols used to model a software system using an object-oriented framework. The symbols can be either informal or formal ranging from predefined graphical templates to formal object models defined by grammars and specifications. A modeling language is usually associated with a methodology for object-oriented development. The modeling language defines the elements of the model. E.g., that a model has classes, methods, object properties, etc. The methodology defines the steps developers and users need to take to develop and maintain a software system. Steps such as Define requirements, Develop code, and Test system. It is common to equate the modeling language and the modeling methodology. For example, the Booch method may refer to Grady Booch's standard for diagramming, his methodology, or both. Or the Rumbaugh Object Modeling Technique is both a set of diagrams and a process model for developing object-oriented systems. In the early years of the object-oriented community there were several competing modeling and methodology standards. Booch and Rumbaugh were two of the most popular. Ivar Jacobson's Objectory, Shlaer-Mellor, and Yourdon-Coad were also popular. However, the object-oriented community values re-use and standardization. As shown in the graphic there were efforts starting in the mid 1990s to reconcile the leading models and focus on one unified specification. The graphic shows the evolution of one of the most important object modeling language standards: the Unified Modeling Language (UML). The UML began as an attempt by some of the major thought leaders in the community to define a standard language at the OOPSLA '95 Conference. Originally, Grady Booch and James Rumbaugh merged their models into a unified model. This was followed by Booch's company Rational Software purchasing Ivar Jacobson's Objectory company and merging their model into the UML. At the time Rational and Objectory were two of the dominant players in the small world of independent vendors of Object-Oriented tools and methods.