We generally try to stick to the official Java Code Conventions. In addition to that, we apply points number 3, 4 and 5 of the conventions outlined by the Apache Turbine project.
The formatting of the JaxoDraw source code can be checked with the Maven checkstyle-plugin. On the command line:
mvn checkstyle:checkstyle
or to generate a report as part of the site:
mvn -Preporting clean site
(this will run a bunch of other reports as well).