Trapdoor 1.16

        if(b.getType() == Material.OAK_TRAPDOOR)
        {
            // Save
            final Material m = b.getType();
            final Location loc = b.getLocation();
            final BlockState bs = b.getState();

            TrapDoor door = (TrapDoor) bs.getBlockData();
            boolean open = door.isOpen();

            if(!open) // if it's closed before interact
                processingDoors.add(b);
            else if(processingDoors.contains(b))
                processingDoors.remove(b);

            new BukkitRunnable()
            {
                public void run()
                {      // to avoid a BlockBreakEvent check
                    if(processingDoors.contains(b) && b.getWorld().getBlockAt(loc).getType() == m) // called
                    {
                        door.setOpen(!open);
                        bs.setBlockData(door);
                        bs.update(true);
                    }
                }

            }.runTaskLater(this, 3 * 20L);
        }