For the most part I prefer to use technologies like JdbcTemplate that only provide a very thin layer between the relational and the object-oriented world. ORM

For the most part I prefer to use technologies like JdbcTemplate that only provide a very thin layer between the relational and the object-oriented world. ORM systems usually try to paper over the impedance mismatch between these two worlds. This mismatch will always be there. There's no way around it. So, we might as well keep the systems dealing with it as simple as possible and not try to force object-orientation on relations and vice versa. Document-oriented database systems are good alternative in many cases, too because by their very nature they're much more amenable to storing objects.