We are starting a new project and I've suggested using Hibernate for persistence. My team lead is interested in Hibernate and has read many good things about it but he is uneasy about using a technology that he doesn't fully understand (which is understandable of course). Of specific concern is how Hibernate manages database connections. I know that Hibernate acts as a client to the connection pool and abstracts away a lot of this from the developer, however I haven't been able to find a good resource to find out all the gory details of what is going on. At what point is a connection made, at what point is it closed, etc? We both feel that Hibernate is very promising and could be a good fit for the application, however we need to demystify some of the 'magic'. Any help or links to this information would be appreciated.