问题
What symbol should I use ?
回答1:
Below is an extract from the Unified Modeling Language specification. The complete specification is available at http://www.omg.org/spec/UML/2.3.
9.5.1 Comment
A comment is a textual annotation that can be attached to a set of elements.
Description
A comment gives the ability to attach various remarks to elements. A comment carries no semantic force, but may contain information that is useful to a modeler. A comment may be owned by any element.
Notation
A Comment is shown as a rectangle with the upper right corner bent (this is also known as a “note symbol”). The rectangle contains the body of the Comment. The connection to each annotated element is shown by a separate dashed line.
Presentation Options
The dashed line connecting the note to the annotated element(s) may be suppressed if it is clear from the context, or not important in this diagram.
来源：https://stackoverflow.com/questions/4003075/can-i-write-comments-in-uml-class-diagram