Is there a javadoc like tool for Objective-C?

I would like to generate documentation for my source files…
AutoDOC.
Assuming HeaderDoc, to automate documentation generation from PB, you can add a new Script shell build phase, invoking a small script like:

hdoc -o MyDocumentationFolder myHeaderFilesList
gdoc MyDocumentationFolder
Apple ships HeaderDoc with the Developer Tools (see /Developer/Documentation/DeveloperTools/HeaderDoc/).
There is also