Getting player health and max health

I am using this method to format my health and max health:

 s = "" + this.formatExp(mc.thePlayer.func_110139_bj(), mc.thePlayer.func_110138_aP()) + " / " + mc.thePlayer.func_110138_aP();

(formatExp is a custom method that just colours stuff)

But this is intended for a Bukkit server, and I am just wondering; is it possible to get the proper health and max health? Because bj() returns 0.0 and aP() always returns 20. Even though on the server I had 100 HP and 100 max hp....