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.
1 depicts 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
The Elements of UML 2.0 Style describes a collection
of standards, conventions, and
for creating effective
UML diagrams. They are based on sound, proven
software engineering principles that lead to diagrams
that are easier to understand and work with. These
conventions exist as a collection of simple, concise
guidelines that if applied consistently, represent an
important first step in increasing your productivity as
a modeler. This book is oriented towards
intermediate to advanced UML modelers, although there
are numerous examples throughout the book it would not
be a good way to learn the UML (instead, consider
The Object Primer). The book is a brief 188
pages long and is conveniently pocket-sized so it's easy
to carry around.
The Object Primer 3rd Edition: Agile Model Driven
Development with UML 2 is an
important reference book for agile modelers,
describing how to develop 35
types of agile
models including all 13
UML 2 diagrams.
Furthermore, this book describes the techniques
Full Lifecycle Object Oriented Testing
(FLOOT) methodology to give you the fundamental
testing skills which you require to succeed at
agile software development. The book also
shows how to move from your agile models to
source code (Java examples are provided) as well
as how to succeed at implementation techniques
(TDD). The Object Primer also includes a
chapter overviewing the critical database
development techniques (database refactoring,
legacy analysis, and
database access coding) from my award-winning
Agile Database Techniques
Agile Modeling: Effective Practices for Extreme
Programming and the Unified Process is the seminal
book describing how agile software developers approach
documentation. It describes principles and
practices which you can tailor into your existing
software process, such as
Rational Unified Process (RUP), or the
Agile Unified Process (AUP), to streamline your
modeling and documentation efforts. Modeling and
documentation are important aspects of any software
project, including agile projects, and this book
describes in detail how to
architect, and then
design your system in an agile manner.
We actively work with clients around the world to
improve their information technology (IT) practices,
typically in the role of mentor/coach, team lead, or trainer. A full
description of what we do, and how to contact us, can be
found at Scott W.
Ambler + Associates.