4.a Modify Hudson Job.
Once you have an Ant target working, calling this from your CI server is trivial. Within Hudson, select your Job, click on configure and add this new target to be called when running the build.
4.b Publish the reports.
4. c: Sample Reports.
Force a build, and take a detailed look at the reports generated by Doxygen as shown below:
I have given you a brief overview of Doxygen in this article, how to configure the same, and use it effectively to generate technical documentation on a continuous basis; either on commit builds or nightly builds. The Doxygen web site has lots of information on how to use it with other programming languages and also has tutorials in languages other than English as well.
As always, if you are having trouble getting Doxygen to work, leave a comment or check out the Doxygen web site.