I stopped getting spinning beachballs when I upgraded to an SSD. OS X, especially pre-Mavericks is a real RAM hog. Java GUI apps have a reputation of being even worse RAM hogs. I wouldn't be surprised to find your spinning beach balls are from swapping to disk.
The only Java app I use is BucketExplorer though, which isn't very heavy.
The only Java app I use is BucketExplorer though, which isn't very heavy.