The core package contains the java implementation of the HEALPix Index. Look in thetest package for example usage.
An ant build file is provided in the src package for building the clases and javadocs.
If you intend to use the htmIndex, please drop an email to William O'Mullane so that you can be notified of any updates, bugfixes, etc in the future.
Also, if you have any bugs to report or wishes on functionality etc., please write to wil.