[xwiki-devs] Help getting started on a table-generating extension

I'm appreciate some pointers on getting started on writing an extension component that retrieves data from an external database and presents it as a table. I have reviewed a lot of the available documentation, but must admit to getting a little lost with the various changes in standards, as a lot of the available code and documentation describes macros, which I believe are now deprecated in favour of components. I am happy creating a new component using the Maven archetype, and writing the necessary code to retrieve data from the external database. What I would like help with are: 1) How can I get the current user, so that I can use this contextual information in my query? 2) How should I return the tabular data? I'm sure these are very naïve questions, but please take pity on me and by all means point me at the relevant documentation if it exists already.