Slightly more complex.
Official java will bleed you dry.
Theres the open java thang - icedtea or whatever.
But you are on your own. Last time i looked oracle did not ship the regression test.
If youve made a sigificant investment in java then youve 3 choices
1- Be bled dry by oracle. Youll pay each time larry has a shit.
2 - Invest in your own java development team - produce your own regression tests for jdk and your apps. A massive commitment because if java is anything its a complex mess.
3- port everything away.
Pick one now.