Player Set Spawn Event 
To use this event use the following import:
groovy
import net.minecraftforge.event.entity.player.PlayerSetSpawnEventSub-Classes 
This event extends the following events and can use all their methods and fields: 
PlayerEvent, LivingEvent, EntityEvent
Methods 
groovy
boolean isForced()groovy
net.minecraft.util.math.BlockPos getNewSpawn()