The HSSF eventmodel package is a new API for reading XLS files more efficiently. It does require more knowledge on the part of the user, but reduces memory consumption by more than tenfold. It is based on the AWT event model in combination with SAX. If you need read-only access to a given XLS file, this is the best way to do it.

Star Office 5.1 writes some records using the older BIFF standard. This causes some problems with POI which supports only BIFF8.