UML class diagram: Difference between revisions
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* Represented on both ends by the following syntax | * Represented on both ends by the following syntax | ||
<table border="1"> | <table border="1"> | ||
<tr><th>Multiplicities</th><th>Explanation</th></tr> | <tr><th>Multiplicities</th><th>Explanation<br/> | ||
The notation <i><b>n . . m</b></i> indicates <i><b>n</b></i> to<i> <b>m</b></i> instances. | |||
</th></tr> | |||
<tr> | <tr> | ||
<td><b>0..1</b></td> | <td><b>0..1</b></td> | ||
<td>zero or one instance | <td>zero or one instance.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<td><b>0..*</b><i> or </i><b>*</b></td> | <td><b>0..*</b><i> or </i><b>*</b></td> | ||
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<td>at least one instance</td> | <td>at least one instance</td> | ||
</tr> | </tr> | ||
</table> | |||
; More | ; More | ||
* There is more ... | * There is more (sorry)... | ||
=== Properties of classes === | === Properties of classes === | ||
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=== IMS Learning Design === | === IMS Learning Design === | ||
== References == | |||
* IMS Learning Design Information Model, Version 1.0 Final Specification, [http://www.imsglobal.org/learningdesign/ldv1p0/imsld_infov1p0.html HTML], retrieved 15:24, 5 June 2007 (MEST). | |||
* Randy Miller, [http://bdn.borland.com/article/0,1410,31863,00.html Practical UML: A Hands-On Introduction for Developers], Borland Developer network. (Short and excellent general UML tutorial). | |||
* Donald Bell, [http://www-128.ibm.com/developerworks/rational/library/769.html UML basics: An introduction to the Unified Modeling Language], IBM Developper Works / Rational Rose. (IBM has a lot of UML and use case tutorials, needs some searching skills) | |||
Revision as of 15:24, 5 June 2007
Definition
UML Class diagrams are one kind of official diagram types of the Unified modeling language (UML)
Architecture
Class diagrams are made with quite a complex "language".
Classes
- Classes are represented with boxes
- Represented by a rectangle with one, two or three "fields": classname, properties and methods
- Relationships in class diagrams
- Association
- A relationship between instances of the two classes
- Represented by: a solid line with an arrow, directed from the source class to the target class
- Aggregation
- A part-of relationship
- Represented by:
- Example: a learning object is part of an environment
- Generalization
- A is-a relationship
- Represented by: A solid line with a triangular arrow from specialized class to class
- Example: Learner is a role
- Composition
- Like aggregation but you can add more constraints.
- An instance of a class can be potentially a component of several classes, but can only be owned by one.
- Multiplicity
- of an association end is the number of possible instances of the class associated with a single instance of the other end.
- Represented on both ends by the following syntax
| Multiplicities | Explanation The notation n . . m indicates n to m instances. |
|---|---|
| 0..1 | zero or one instance. |
| 0..* or * | no limit on the number of instances (including none). |
| 1 | exactly one instance |
| 1..* | at least one instance |
- More
- There is more (sorry)...
Properties of classes
Examples
IMS Learning Design
References
- IMS Learning Design Information Model, Version 1.0 Final Specification, HTML, retrieved 15:24, 5 June 2007 (MEST).
- Randy Miller, Practical UML: A Hands-On Introduction for Developers, Borland Developer network. (Short and excellent general UML tutorial).
- Donald Bell, UML basics: An introduction to the Unified Modeling Language, IBM Developper Works / Rational Rose. (IBM has a lot of UML and use case tutorials, needs some searching skills)