|
Understanding the thirteen diagrams
of UML 2.x is an important part of understanding OO
development. Although there is
far more to modeling than just the UML the reality
is the UML defines the standard modeling artifacts when
it comes to object technology.
There are three classifications of UML diagrams:
- Behavior diagrams. A type of diagram that
depicts behavioral features of a system or business
process. This includes activity, state machine, and
use case diagrams as well as the four interaction
diagrams.
- Interaction diagrams. A subset of behavior
diagrams which emphasize object interactions. This
includes communication, interaction overview,
sequence, and timing diagrams.
- Structure diagrams. A type of diagram that
depicts the elements of a specification that are
irrespective of time. This includes class, composite
structure, component, deployment, object, and package
diagrams.
Table 1
summarizes the thirteen, up from nine in UML 1.x,
diagram types of UML 2.x. In the diagram column
the links will take you to description pages for the
artifact. The learning priority column indicates
how important it is for a business application developer
to learn the artifact (IMHO).
Table 1. The diagrams of
UML 2.
|
Diagram |
Description |
Learning Priority |
|
Activity Diagram |
Depicts high-level business
processes, including data flow, or to model the
logic of complex logic within a system. See
UML Activity diagram guidelines. |
High |
|
Class Diagram |
Shows a collection of static
model elements such as classes and types, their
contents, and their relationships. See
UML Class diagram guidelines. |
High |
|
Communication Diagram |
Shows instances of classes,
their interrelationships, and the message flow
between them. Communication diagrams typically focus
on the structural organization of objects that send
and receive messages. Formerly called a
Collaboration Diagram. See
UML Collaboration diagram guidelines. |
Low |
|
Component Diagram |
Depicts the components that
compose an application, system, or enterprise. The
components, their interrelationships, interactions,
and their public interfaces are depicted. See
UML Component diagram guidelines. |
Medium |
|
Composite Structure Diagram |
Depicts the internal structure
of a classifier (such as a class, component, or use
case), including the interaction points of the
classifier to other parts of the system.
|
Low |
|
Deployment Diagram |
Shows the execution
architecture of systems. This includes nodes,
either hardware or software execution environments,
as well as the middleware connecting them. See
UML Deployment diagram guidelines. |
Medium |
|
Interaction Overview Diagram |
A variant of an activity
diagram which overviews the control flow within a
system or business process. Each
node/activity within the diagram can represent
another interaction diagram. |
Low |
|
Object Diagram |
Depicts objects and their
relationships at a point in time, typically a
special case of either a class diagram or a
communication diagram. |
Low |
|
Package Diagram |
Shows how model elements are
organized into packages as well as the dependencies
between packages. See
Package
diagram guidelines. |
Low |
|
Sequence Diagram |
Models the sequential logic, in
effect the time ordering of messages between
classifiers. See
UML Sequence diagram guidelines. |
High |
|
State Machine Diagram |
Describes the states an object
or interaction may be in, as well as the transitions
between states. Formerly referred to as a state
diagram, state chart diagram, or a state-transition
diagram. See
UML State chart diagram guidelines. |
Medium |
|
Timing Diagram |
Depicts the change in state or
condition of a classifier instance or role over
time. Typically used to show the change in
state of an object over time in response to external
events. |
Low |
|
Use Case Diagram |
Shows use cases, actors, and
their interrelationships. See
UML Use case diagram guidelines. |
Medium |
This material has been excerpted from
The Object Primer 3rd Edition: Agile Modeling Driven
Development with UML 2.
|
|