net.minecraftforge.eventbus.api.Event

net.minecraftforge.event.entity.EntityEvent

net.minecraftforge.event.entity.living.MobSpawnEvent

net.minecraftforge.event.entity.living.MobSpawnEvent.FinalizeSpawn

Enclosing class:: MobSpawnEvent

public static class MobSpawnEvent.FinalizeSpawn extends MobSpawnEvent

This event is fired before

Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag)

is called.
This allows mods to control mob initialization.
In vanilla code, this event is injected by a transformer and not via patch, so calls cannot be traced via call hierarchy (it is not source-visible).

Canceling this event will result in Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) not being called, and the returned value always being null, instead of propagating the SpawnGroupData.
The entity will still be spawned. If you want to prevent the spawn, use setSpawnCancelled(boolean), which will cause Forge to prevent the spawn.

This event is fired on MinecraftForge.EVENT_BUS, and is only fired on the logical server.

See Also:

ForgeEventFactory.onFinalizeSpawn(net.minecraft.world.entity.Mob, net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag)

Nested Class Summary

Nested classes/interfaces inherited from class net.minecraftforge.event.entity.living.MobSpawnEvent
MobSpawnEvent.AllowDespawn, MobSpawnEvent.FinalizeSpawn, MobSpawnEvent.PositionCheck, MobSpawnEvent.SpawnPlacementCheck

Nested classes/interfaces inherited from class net.minecraftforge.event.entity.EntityEvent
EntityEvent.EnteringSection, EntityEvent.EntityConstructing, EntityEvent.EyeHeight, EntityEvent.Size

Nested classes/interfaces inherited from class net.minecraftforge.eventbus.api.Event
net.minecraftforge.eventbus.api.Event.HasResult, net.minecraftforge.eventbus.api.Event.Result
Field Summary

Fields

Modifier and Type

Field

Description

private DifficultyInstance

difficulty

private @Nullable SpawnGroupData

spawnData

private final @Nullable BaseSpawner

spawner

private @Nullable CompoundTag

spawnTag

private final MobSpawnType

spawnType
Constructor Summary

Constructors

Constructor

Description

FinalizeSpawn(Mob entity, ServerLevelAccessor level, double x, double y, double z, DifficultyInstance difficulty, MobSpawnType spawnType, @Nullable SpawnGroupData spawnData, @Nullable CompoundTag spawnTag, @Nullable BaseSpawner spawner)
Method Summary

Modifier and Type

Method

Description

DifficultyInstance

getDifficulty()

Retrieves the DifficultyInstance for the chunk where the mob is about to be spawned.

@Nullable SpawnGroupData

getSpawnData()

Retrieves the SpawnGroupData for this entity.

@Nullable BaseSpawner

getSpawner()

Retrieves the underlying BaseSpawner instance if this mob was created by a Mob Spawner of some form.

@Nullable CompoundTag

getSpawnTag()

This is the NBT data the entity was loaded from, if applicable.

MobSpawnType

getSpawnType()

Retrieves the type of mob spawn that happened (the event that caused the spawn).

boolean

isSpawnCancelled()

Returns the current spawn cancellation status, which can be changed via setSpawnCancelled(boolean).

void

setDifficulty(DifficultyInstance inst)

Sets the difficulty instance for this event, which will be propagated to Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) unless cancelled.

void

setSpawnCancelled(boolean cancel)

This method can be used to cancel the spawn of this mob.

void

setSpawnData(@Nullable SpawnGroupData data)

Sets the spawn data for this entity.

void

setSpawnTag(@Nullable CompoundTag tag)

Sets the spawn data for this event, which will be propagated to Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) unless cancelled.

Methods inherited from class net.minecraftforge.event.entity.living.MobSpawnEvent
getEntity, getLevel, getX, getY, getZ

Methods inherited from class net.minecraftforge.eventbus.api.Event
getListenerList, getPhase, getResult, hasResult, isCancelable, isCanceled, setCanceled, setPhase, setResult

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- spawnType
  
  private final MobSpawnType spawnType
- spawner
  
  @Nullable private final @Nullable BaseSpawner spawner
- difficulty
  
  private DifficultyInstance difficulty
- spawnData
  
  @Nullable private @Nullable SpawnGroupData spawnData
- spawnTag
  
  @Nullable private @Nullable CompoundTag spawnTag
Constructor Details
- FinalizeSpawn
  
  @Internal public FinalizeSpawn(Mob entity, ServerLevelAccessor level, double x, double y, double z, DifficultyInstance difficulty, MobSpawnType spawnType, @Nullable @Nullable SpawnGroupData spawnData, @Nullable @Nullable CompoundTag spawnTag, @Nullable @Nullable BaseSpawner spawner)
Method Details
- getDifficulty
  
  public DifficultyInstance getDifficulty()
  
  Retrieves the DifficultyInstance for the chunk where the mob is about to be spawned.
  
  Returns:
  
  The local difficulty instance
- setDifficulty
  
  public void setDifficulty(DifficultyInstance inst)
  
  Sets the difficulty instance for this event, which will be propagated to Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) unless cancelled. The difficulty instance controls how likely certain random effects are to occur, or if certain mob abilities are enabled.
  
  Parameters:
  
  inst - The new difficulty instance.
- getSpawnType
  
  public MobSpawnType getSpawnType()
  
  Retrieves the type of mob spawn that happened (the event that caused the spawn). The enum names are self-explanatory.
  Returns:
  
  The mob spawn type.
  
  See Also:
  
  MobSpawnType
- getSpawnData
  
  @Nullable public @Nullable SpawnGroupData getSpawnData()
  
  Retrieves the SpawnGroupData for this entity. When spawning mobs in a loop, this group data is used for the entire group and impacts future spawns. This is how entities like horses ensure that the whole group spawns as a single variant. How this is used varies on a per-entity basis.
  
  Returns:
  
  The spawn group data.
- setSpawnData
  
  public void setSpawnData(@Nullable @Nullable SpawnGroupData data)
  
  Sets the spawn data for this entity. If this event is cancelled, this value is not used, since Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) will not be called.
  Parameters:
  
  data - The new spawn data
  
  See Also:
  
  getSpawnData()
- getSpawnTag
  
  @Nullable public @Nullable CompoundTag getSpawnTag()
  
  This is the NBT data the entity was loaded from, if applicable. It is unknown if the entity has already been loaded from this data, or if it will be loaded later. Callers should not modify this data. If you need to change the data, you can create a copy, modify it, and set it via setSpawnTag(net.minecraft.nbt.CompoundTag)
  
  Returns:
  
  The spawn data this entity was or will be loaded from, if any.
- setSpawnTag
  
  public void setSpawnTag(@Nullable @Nullable CompoundTag tag)
  
  Sets the spawn data for this event, which will be propagated to Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) unless cancelled. The only vanilla mob known to use this tag for anything in finalize is tropical fish for setting the variant when spawned via bucket.
  
  Parameters:
  
  tag - The new spawn tag
- getSpawner
  
  @Nullable public @Nullable BaseSpawner getSpawner()
  
  Retrieves the underlying BaseSpawner instance if this mob was created by a Mob Spawner of some form. This is always null unless getSpawnType() is MobSpawnType.SPAWNER, and may still be null even then.
  
  Returns:
  
  The BaseSpawner responsible for triggering the spawn, or null if none is available.
- setSpawnCancelled
  
  public void setSpawnCancelled(boolean cancel)
  
  This method can be used to cancel the spawn of this mob.
  This method must be used if you want to block the spawn, as canceling the event only blocks the call to Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag).
  Note that if the spawn is cancelled, but the event is not, then Mob.finalizeSpawn(net.minecraft.world.level.ServerLevelAccessor, net.minecraft.world.DifficultyInstance, net.minecraft.world.entity.MobSpawnType, net.minecraft.world.entity.SpawnGroupData, net.minecraft.nbt.CompoundTag) will still be called, but the entity will not be spawned. Usually that has no side effects, but callers should be aware.
  
  Parameters:
  
  cancel - If the spawn should be cancelled (or not).
- isSpawnCancelled
  
  public boolean isSpawnCancelled()
  
  Returns the current spawn cancellation status, which can be changed via setSpawnCancelled(boolean).
  
  Returns:
  
  If this mob's spawn is cancelled or not.

Class MobSpawnEvent.FinalizeSpawn

Nested Class Summary

Nested classes/interfaces inherited from class net.minecraftforge.event.entity.living.MobSpawnEvent

Nested classes/interfaces inherited from class net.minecraftforge.event.entity.EntityEvent

Nested classes/interfaces inherited from class net.minecraftforge.eventbus.api.Event

Field Summary

Constructor Summary

Method Summary

Methods inherited from class net.minecraftforge.event.entity.living.MobSpawnEvent

Methods inherited from class net.minecraftforge.eventbus.api.Event

Methods inherited from class java.lang.Object

Field Details

spawnType

spawner

difficulty

spawnData

spawnTag

Constructor Details

FinalizeSpawn

Method Details

getDifficulty

setDifficulty

getSpawnType

getSpawnData

setSpawnData

getSpawnTag

setSpawnTag

getSpawner

setSpawnCancelled

isSpawnCancelled