3 - Guidelines for Common UML Modeling Elements

Summary

An important benefit of the UML is that it is consistent, and part of that consistency is the application of common modeling elements across different diagrams. This chapter describes guidelines for

1. ■ Notes

2. ■ Stereotypes

3. ■ Frames

4. ■ Interfaces

Guidelines for UML Notes

A UML note is a modeling construct for adding textual information—such as a comment, constraint definition, or method body—to UML diagrams. As you can see in Figure 6, notes are depicted as rectangles with the top right corners folded over.

Describe Diagrams with Notes

Ever look at a diagram and not know what it represents? A simple solution is to include a UML note on each diagram that provides a simple and concise description. This is often referred to as a “legend.” In Figure 6 you can see that the name of the system, the purpose of the diagram, and its owner are indicated. It is common also to indicate when the diagram was last updated and the contact information for the owner.

Set a Convention for Placement of Diagram Legends

Placing diagram legends in the same place on all your diagrams increases their usability by making them easy to find. Common spots are one of the corners or the bottom center of a diagram.

Left-Justify Text in Notes

It is common practice to left-justify text in UML notes, as you can see in Figure 6.

Prefer Notes over OCL or ASL to Indicate Constraints

Source code, describing a constraint or processing logic, can be modeled on any UML diagram using a note.