HashMap<Material, Location> block = new HashMap<>();

    @EventHandler
    public void Blockläufer(PlayerMoveEvent e) {
        Player p = e.getPlayer();
        if (p.hasMetadata("angel")) {
            if (p.getLocation().add(0, -1, 0).getBlock().getType().equals(Material.AIR)) {
                p.getLocation().add(0, -1, 0).getBlock().setType(Material.GLASS);
                block.put(Material.GLASS, p.getLocation().add(0,-1,0));
                Bukkit.getScheduler().scheduleAsyncDelayedTask(Main.getPlugin(), new Runnable() {
                    @Override
                    public void run() {
                        Bukkit.getScheduler().runTask(Main.getPlugin(), new Runnable() {
                            @Override
                            public void run() {
                                block.get(Material.GLASS).getBlock().setType(Material.AIR);
                                Bukkit.broadcastMessage("remove");
                            }
                        });
                    }
                }, 20);
            }
        }
    }