http://jd.bukkit.org/rb/doxygen/d4/dae/interfaceorg_1_1bukkit_1_1entity_1_1Damageable.html LivingEntity e=bla; e.getHealth();
You have your project setup wrong. More information on this here: http://forums.bukkit.org/threads/oops-i-didnt-break-your-plugins-ambiguous-gethealth.156975/