@EventHandler
	    public void PlayerOpen(final InventoryOpenEvent event) {
	            event.getPlayer().addPotionEffect(new PotionEffect(PotionEffectType.BLINDNESS, 100000, 200));
	        }

	    @EventHandler
	    public void PlayerClose(final InventoryCloseEvent event) {
	        final Player player = (Player)event.getPlayer();
	        for (final PotionEffect potionEffect : player.getActivePotionEffects()) {
	            player.removePotionEffect(potionEffect.getType());
	        }
	    }
}