This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
He mentioned that he is already using PHP on port 80, so I assume that he already runs Apache HTTP Server on that for PHP purposes and that he want to add JSP/Servlet access to that. In this case, use the mod_jk.