Runnable

package ua.coolboy.skullfinder;

import org.bukkit.Bukkit;
import org.bukkit.Color;
import org.bukkit.FireworkEffect;
import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.Particle;
import org.bukkit.Sound;
import org.bukkit.World;
import org.bukkit.block.Skull;
import org.bukkit.entity.ArmorStand;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.meta.SkullMeta;
import org.bukkit.scheduler.BukkitRunnable;

public class StandFlyRunnable extends BukkitRunnable {

    ArmorStand stand;
    Skull skull;
    World world;

    public StandFlyRunnable(ArmorStand stand, Skull skull) {
        this.stand = stand;
        this.skull = skull;
        this.world = stand.getWorld();
    }

    @Override
    public void run() {
        stand.setGravity(false);
        stand.setMarker(false);
        stand.setInvulnerable(true);
        stand.setVisible(false);
        stand.setCustomNameVisible(false);
        stand.setCustomName("Flying Skull");
        double start = stand.getHeadPose().getY();
        int skip = 0;
        synchronized (this) {
            for (int i = 0; i < 1000; i++) {
                Location location = stand.getLocation();
                location.add(0, 0.006, 0);
                stand.teleport(location);
                double rad = Math.pow((float)i / 400, 2) * Math.PI;
                stand.setHeadPose(stand.getHeadPose().setY(start + rad));
                skip++;
                if(skip % 4 == 0) {
                    world.spawnParticle(Particle.REDSTONE, stand.getEyeLocation().subtract(0, 0.5, 0), 0, Float.MIN_VALUE, 1, 0.5, 1);
                }
                if (skip == 15) {
                    world.playSound(stand.getLocation(), Sound.BLOCK_NOTE_HARP, 0.5F, 0);
                }
                if (skip >= 40) {
                    world.playSound(stand.getLocation(), Sound.BLOCK_NOTE_HARP, 0.5F, 1);
                    skip = 0;
                }
                try {
                    this.wait(5);
                } catch (InterruptedException ex) {
                    Bukkit.getLogger().warning("Oops! Something went wrong during stand fly!");
                    stand.remove();
                    this.cancel();
                    break;
                }
            }
            stand.remove();
            new BukkitRunnable() {
                @Override
                public void run() {
                    FireworkUtil.custom(stand.getEyeLocation(), 1, true, Color.BLUE, Color.RED, Color.SILVER, FireworkEffect.Type.BURST, true);
                }
            }.runTask(SkullFinder.getInstance());
        }
        this.cancel();
    }
}