I had trouble compiling with the latest Bukkit 1.7.2 and Java 1.7_45

The issue was here projectile.getClass(), that wouldn't return the Material value it needed. I presume it has changed scope possible.

The fixed was easy I just changed the this projectile.getLocation().getBlock().getType() and it all worked fine.

Thought I'd let you know if it is causing you any issues.