Unified Modelling Language
The Unified Modelling Language (UML®) was developed to enable the
modelling of a variety of crucial aspects of systems. The UML enables a
system designer to move between models that elucidate a variety of aspects of
the system under construction. The models are created either directly in a tool
or by reverse engineering of previously written code. In the latter case, the
tool creates a model that corresponds with the code: the better quality tools
enable not only reverse engineering, but "round trip"
development.
We use Rhapsody®, which is developed by IBM Rational/Telelogic as our UML
platform. It offers a comprehensive implementation of the UML, which is particularly suited to the
development of real time and embedded applications.
-
Use Case diagrams define the structure of the specification of the system.
The
Use Cases themselves will typically be linked with documentation
managed by a requirements management tool, which defines them.
-
Scenarios are models of a particular sequence of events that take place inside
a system as part of a Use Case. They enable the designer to experiment with
aspects of the system to verify that it will implement a part of the
specification correctly.
-
Class diagrams may be created to define the logical structure of the code in a
system. They help the designer to partition the system into components of
suitable sizes and to identify where previously written code may be imported
to assist the system's construction.
-
State diagrams enable the designer to consider how objects (and possibly Use
Cases) function in the system in a formal manner.
-
Activity diagrams model the flow of control through a system whilst it is being
developed.
-
Component diagrams define the physical structure of a software system. The
modelled components effectively control how the software is partitioned into
modular components.
Overall, these models form both a basis for experimentation with a system under
construction and the means by which the system implementation may be linked
with its specification.
Please see our Products pages for further information
on how links may be established between Use Cases and UML artefacts.
A Use Case specification is defined by identifying the things with which your
system interacts (called "Actors"). Your system performs a number of services
on behalf of these Actors, which are its "Use Cases". A single Use Case is the
definition of a logical flow of functionality in your system.