Minecraft Bukkit Coding Rgen One Block At A Time

public class BlockRegen extends JavaPlugin implements Listener {

    public void onEnable() {
            Bukkit.getServer().getPluginManager().registerEvents(this, this);
    }

    @EventHandler
    public void onEntityExplode(EntityExplodeEvent e) {
    	if (!e.blockList().isEmpty()) {
    		final List<BlockState> blocks = new ArrayList<BlockState>();
    		for (Block b : e.blockList()) {
    		if (b.getType() != Material.AIR) {
    		if (!blocks.contains(b.getState())) {
    		blocks.add(b.getState());
    		b.setType(Material.AIR);


    		}
    		}
    		}
    		new BukkitRunnable() {
    		int i = 17;
    		public void run() {
    		if (i>0){
    		i--;
    		}else{
    		regen(blocks, false, 5);
    		this.cancel();
    		}
    		}
    		}.runTaskTimer(this, 3, 3);
    	}
    }

	protected void regen(List<BlockState> blocks, boolean effect, int speed) {
		new BukkitRunnable() {
			int i = -1;
			@SuppressWarnings("deprecation")
			public void run() {
			if (i != blocks.size()-1) {
			i++;
			BlockState bs = blocks.get(i);
			bs.getBlock().setType(bs.getType());
			bs.getBlock().setData(bs.getData().getData());

			bs.getBlock().getWorld().playEffect(bs.getLocation(), Effect.STEP_SOUND, bs.getBlock().getType());
			bs.getBlock().getWorld().playEffect(bs.getLocation(), Effect.STEP_SOUND, bs.getBlock().getData());




			}

			}