You could create a symlink, or alternatively you could add /usr/java/bin to your path. PATH is a bash environment variable that determines where to look for commands. In order to add /usr/java/bin to your search path, just run "export PATH=$PATH:/usr/java/bin". Each location in the PATH variable is separated by a colon, so what you're doing here is literally setting the PATH variable to its current contents ($PATH returns the contents of PATH as a string, i.e run "echo $PATH" to see what I mean) with ":/usr/java/bin" amended to it.
That will only set your PATH for the current session. To make the changes permanents, edit .bash_profile in your home directory. It may already have some kind of PATH variable modification in it (i.e mine has "PATH=$PATH:$HOME/bin" with "export PATH" on another line), in which case you just amend the line in question. Anyhow, it should be pretty self-explanatory by now.