is a UML diagram
composed only of packages and the dependencies between them.
A package is a UML construct that enables you to organize model elements,
such as use cases or classes, into groups. Packages are depicted as file
folders and can be applied on any UML
diagram. Create a package diagram to:
There are guidelines for:
Case Package Diagrams
Figure 1. A class package diagram.
- Create UML Component Diagrams to Physically Organize Your Design.
- Place Subpackages Below Parent Packages.
- Vertically Layer Class Package Diagrams.
- Create Class Package Diagrams to Logically Organize Your Design.
1depicts a UML Class diagram organized into packages. In addition to the package guidelines presented below, apply the
following heuristics to organize UML Class diagrams into package diagrams:
the classes of a framework in the same package.
in the same inheritance hierarchy typically belong in the same package.
related to one another via aggregation or composition often belong in the
that collaborate with each other a lot, information that is reflected by
your UML Sequence diagrams and UML Collaboration diagrams, often belong in
the same package.
Use cases are often a primary requirement artifact in object-oriented
development methodologies, this is particularly true of instantiations of the
Unified Process, and for
larger projects package diagrams are often created to organize these usage
Figure 2. A UML Use Case diagram
comprised mostly of packages.
- Create Use Case Package Diagrams to Organize Your Requirements
- Include Actors on Use Case Package Diagrams
- Horizontally Arrange Use Case Package Diagrams
The advice presented in this section is applicable to the
application of packages on any UML diagram, not just package diagrams.
- Give Packages Simple, Descriptive Names
- Apply Packages to Simplify Diagrams
- Packages Should be Cohesive
- Indicate Architectural Layers With Stereotypes on Packages
- Avoid Cyclic Dependencies Between Packages
- Package Dependencies Should Reflect Internal Relationships