The ln -s will get you going. You can also put java in the PATH variable. Here is how:

After you have succesfully installed Java, you need to make it accesible by modiying the PATH variable to include the java directory in the path. There a several way to do this. I prefer to make it a system wide change so I modify /etc/profile to have a line like this

PATH=<javadirectory>:$PATH

where <javadirectory> is where java got installed. The directory will be different according to the version you installed. To find out do this command:

find /usr/ -name "*j2*"

The java directory will j2re- in the name.

<javadirectory> must be fully qualified so it should look something like:

/usr/java/j2re-bla,bla,bla...

Note: If you installed from the self extracting instead of the rpm, you migh have installed java in some other directory like /usr/local/.