Which Java on Fedora? Sun's or GNU's?

[AJ]

Hi,

Which is best?
Which is preferred?
If Sun's JRE is better, then how do I get it installed so that the 
Cassandra rpm/yum installer recognizes it?

I was trying to install the Cassandra 0.7.0-rc3 rpm release and it 
doesn't recognize the installed jre from Sun, so the install fails.  
This was on Oracle's RHEL.  But, I think I'm going to ditch Oracle and 
go with Fedora since Cassandra seems to support it, right?

Thanks,
aj