How is the documentation of the API done?
A reference like documentation consists within the IDL files. The syntax of the documentation is based on JavaDoc with a few extensions to mark identifiers. We are currently developing a new generator for this syntax which will generate HTML documents directly from the IDLs. Our Developers Guide describes the concepts of all components within OpenOffice.org which have an API. It is the best resource to start learning about the API. Additionally we have a tutorial for StarBASIC programmers. It explains the basic concepts, shows some UML diagrams of the component structure and has plenty of documented examples of the API usage.