Break Event 
To use this event use the following import:
groovy
import net.minecraftforge.event.world.BlockEvent.BreakEventSub-Classes 
This event extends the following events and can use all their methods and fields: 
BlockEvent
Methods 
groovy
net.minecraft.entity.player.EntityPlayer getPlayer()groovy
int getExpToDrop()groovy
void setExpToDrop(int arg0)