Folks,<P>Being a Perl hacker, I'm having a bit of a hard time figuring out how to do some things in Java...<P>In Perl, I constantly use hashes of hashes to store lots of data in memory, in key-value ...

The Jakarta Persistence API (JPA) is a Java specification that bridges the gap between relational databases and object-oriented programming. This two-part tutorial introduces JPA and explains how Java ...