I was searching for ways to generate xml feeds ( ATOM / RSS ) using Java. It appeared to be trivial task but its not. There are so many different libraries in Java which are capable of reading and writing XML in Java that it became a daunting task to evaulate them. After a bit of experimentation I have settled down with JDOM. JDOM is so simple to use.
On top of that, ROME tools make it even easier to read/write feeds using Java. There is a very nice tutorial availabe to use ROME tools. Not just that, ROME tools have a bunch of modules so that you can add more information to your feeds.