Understanding the UML diagrams is an important part of understanding and performing object-oriented analysis and design in software development.
UML, short for Unified Modeling Language, is a standardized modeling language consisting of an integrated set of diagrams, developed to help system and software developers for specifying, visualizing, constructing, and documenting the artifacts of software systems. The UML uses mostly graphical notations to express the design of software projects.
There are three classifications of UML 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.
- 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.
|
Diagram
|
Description
|
|
Activity Diagram
|
Depicts high-level business processes, including data flow, or to model the logic of complex logic within a system.
|
|
Class Diagram
|
Shows a collection of static model elements such as classes and types, their contents, and their relationships.
|
|
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.
|
|
Component Diagram
|
Depicts the components that compose an application, system, or enterprise. The components, their interrelationships, interactions, and their public interfaces are depicted.
|
|
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.
|
|
Deployment Diagram
|
Shows the execution architecture of systems. This includes nodes, either hardware or software execution environments, as well as the middleware connecting them.
|
|
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.
|
|
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.
|
|
Package Diagram
|
Shows how model elements are organized into packages as well as the dependencies between packages.
|
|
Sequence Diagram
|
Models the sequential logic, in effect the time ordering of messages between classifiers.
|
|
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.
|
|
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.
|
|
Use Case Diagram
|
Shows use cases, actors, and their interrelationships.
|
|
In Visual Studio, a component diagram shows the parts of a design for a software system. A component diagram helps you visualize the high-level structure of the system and the service behavior that those pieces provide and consume through interfaces. To create a UML component diagram, on the Architecture menu, click New UML or Layer Diagram.
The following table describes the elements that you can use on a component diagram, together with their main properties.
|