Hide a Player From Monster?

I know how to hide a player from players, but how do you do the same with monsters? This is what I have for players

Code:

for(Player players : Bukkit.getOnlinePlayers()){
                players.hidePlayer(event.getPlayer());
            }

I was trying something like this for monsters but I can't do .hidePlayer

Code:

for(Entity ent : event.getPlayer().getWorld().getEntities()){

 

You could try adding a potion effect to the entity

Code:

PotionEffect effect = new PotionEffect(PotionEffectType.INVISIBILITY, /*A Duration*/, /*An Amplifier*/);
effect.apply(entity);
 

 

Use the target event.

Get the target event, Then cancel it.

 

Ok thanks

I used this

Code:

public void noSee(EntityTargetLivingEntityEvent event){
        Player target = (Player) event.getTarget();
        if(target instanceof Player){
            if(plugin.invisible.contains(target.getName().toLowerCase())){
                event.setCancelled(true);
            }
        }

And it works except for with spiders lol... Do you know what's wrong?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

I'd do that like this.
You are also using the wrong event?

Only slimes don't fire this event :\

Code:

  public void noSee(EntityTargetEvent event) {
    if (event.getTarget() instanceof Player) {
      Player target = (Player) event.getTarget();
      if (plugin.invisible.contains(target.getName().toLowerCase())) {
        event.setCancelled(true);
      }
    }
  ]