RATIONAL MACHINES was founded by Paul Levy and Mike Devlin in 1981 to
provide tools to expand the use of modern software engineering
practices, particularly explicit modular architecture and iterative
development . It changed its name in 1994 to RATIONAL SOFTWARE, and
was sold for US$2.1 billion (equivalent to current US$2.73 billion )
* 1 Rational Environment * 2 Organization * 3 Second-generation products * 4 UML and RUP * 5 Acquisitions * 6 See also * 7 References * 8 External links * 9 Alternative products
First released in 1985, the Rational Environment was an integrated
development environment for the
Ada programming language
The Rational Environment was organized around a persistent intermediate representation (DIANA ), providing users with syntactic and semantic completion, incremental compilation, and integrated configuration management and version control. To overcome a conflict between strong typing and iterative development that produced recompilation times proportional to system size rather than size-of-change, the Rational Environment supported the definition of subsystems with explicit architectural imports and exports; this mechanism later proved useful in protecting application architectures from inadvertent degradation. The Environment's Command Window mechanism made it easy to directly invoke Ada functions and procedures, which encouraged developer-driven unit testing.
The Rational Environment ran on custom hardware, the Rational R1000 , which implemented a high-level architecture optimized for execution of Ada programs in general and the Rational Environment in particular. The horizontally-microprogrammed R1000 provided two independent 64-bit data paths, permitting simultaneous computation and type checking. Memory was organized as a single-level store; a 64-bit virtual address presented to the memory system either immediately returned data, or triggered a page fault handled by the processor's microcode.
The company's name was later changed from "Rational Machines" to
Rational provided code generators and the cross-debuggers for
then-popular instruction set architectures such as the
Rational's field Practices underlying the later Rational Unified Process (RUP) - iterative development, component-based architecture, modelling, continuous developer-driven testing, requirements management, and automated testing—are all traceable to this experience base.
In 1990, Rational launched three parallel development efforts:
re-implementation of the Rational Environment (for Ada) to run on Unix
-based workstations from Sun and
Rose 1.0 was introduced at OOPSLA in 1992, but performed poorly in multiple dimensions and was withdrawn from the market.
The development of Rose 2.0 combined a Windows-based Booch notation
editor called Object System Designer (acquired from
UML AND RUP
In 1994, Rational merged with
Verdix , a public company that produced
a wide array of Ada compilers targeted to many architecture/OS
combinations. The resulting entity was named "Rational Software", and
promptly integrated the Rational Ada and
Philippe Kruchten , a Rational techrep, was tasked with the assembly
of an explicit process framework for modern software engineering. This
effort combined the
* a tailorable process that guided development * tools that automated the application of that process * services that accelerated adoption of both the process and the tools.
The momentum generated by Rose and the UML enabled Rational to establish a partnership with Windows platform developers. Rational's aim was to secure Microsoft's public support for visual modeling.
Rational peaked at US$850M in revenues (current equivalent US$1.11
billion ) and 4000 employees. After the dot-com crash , its revenues
declined to $650M, but it was dominant, profitable, and cash-rich
(~$600M) when its founders chose to sell the company to
Rational Application Developer
Rational Asset Manager
Rational Automation Framework
Rational Business Developer
Rational Quality Manager
* ^ A B C Federal Reserve Bank of Minneapolis Community Development
Project. "Consumer Price Index (estimate) 1800–". Federal Reserve
Bank of Minneapolis. Retrieved January 2, 2017.
* ^ "Merger with Verdix". RATL. 2002-06-01. Retrieved 2014-01-05
– via web.archive.org.
* ^ "