Take a look at
NetBeans[
^] - it's a very nice IDE for java.
Over at
Apache.org[
^] you'll find a serious amount of quality open source java projects. I suggest you look at
Commons cli[
^] - it's a rather small library, that does something useful. Starting out with something as complex as
Apache Camel[
^] will probably just be a source of frustration.
Best regards
Espen Harlinn