I would try using Entity.getType() and then check if it is EntityType.SHEEP and just work off of that. Here are some useful links to help you out: Entity (org.bukkit.entity) EntityType (org.bukkit.entity) Sheep (org.bukkit.entity) You should always look at the Java-Doc for Bukkit, it usually helps you with these kinds of questions.
If you look at those links DealerNextDoor posted, you'll see the Sheep extends Colorable, and the method you want is getColor() So, you'll have to cast your entity, once you've checked that it's a Sheep Code: DyeColor color = ((Colorable) entity).getColor();