writes "From a documentation point of view, Hibernate is one of the most notable exception in the world of LGPL'ed projects. Its website offers a plethora of information, from solid documentation (the reference has no less than 141 pages) and various FAQs to sample projects and third-party resources. The forum is quite active and you may get answers to tricky questions. Or a little bit of rough treatment in case you haven't RTFM - but that is understandable, given the number of questions that the authors have to answer every day. Under these circumstances, one might wonder what Gavin King (Hibernate founder) and Christian Bauer (documentation/website maintainer and Hibernate core developer) can add in order to be able to write a 400-pages book about Hibernate. I mean - sure - only by joining the reference documentation, different FAQs and guides, one can easily 'extract' a hefty 'manuscript' with more than 200 pages."
Read on for Spinei's review of Hibernate in Action