Ok, in your home directory, there is a file called .bash_profile . If there isn't, you'd better make sure your account is set up correctly... So, you can either add this line at the end:

export PATH=${PATH}:/usr/local
or do this:
(by the way, this is personally how I would do it, since I like having a short $PATH...)

ln -s /usr/local/java /usr/bin/
(as root)

All of this is assuming "/usr/local/java" is the binary file, as opposed to a directory containing the java files... A good way to check that is to type /usr/local/java, and if it executes, follow the above directions... If it gives you an error, you need to find the binaries, and add their directory to your path, or link them to a place already in your path.