Violet and VPL Database Manual

Don Batory
Department of Computer Science
The University of Texas at Austin
Austin, TX, USA

Violet is a free Java tool for  drawing UML class diagrams. Familiarize yourself with Violet by installing MDELite and invoking it:
> java MDL.Violet
and drawing the diagram below:



Draw your own diagrams.  When you feel comfortable, proceed to the next section.

Violet Database Schema

Violet encodes a class diagram as an ugly XML file.  The MDL.ClassVioletParser tool translates Violet-XML documents into a database that conforms to the following schema:
:::libpl/vpl.schema.pl:::
Some notes:Let SC.class.violet be the Violet-produced XML file for StudentCourse. The following MDELite command translates this file into a VPL database SC.vpl.pl:
> java MDL.VioletClassParser SC.class.violet SC.vpl.pl
The database that is produced is:
:::outViolet.txt:::

VPL Constraints

There indeed are VPL constraints.  I have not posted them, as they are good examples for homework assignments.  They are similar to those for YPL (VPL's Yuml counterpart).