i have a problem with fireworks

hello guys, i have a problem with fireworks, when a player join to the server with the permission, the firework does not appears.
this is my current code:

Code:

package main;

import java.util.Random;
import org.bukkit.Color;
import org.bukkit.FireworkEffect;
import org.bukkit.entity.EntityType;
import org.bukkit.entity.Firework;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.inventory.meta.FireworkMeta;

public class JoinFirework
  implements Listener
  {
      Integer i;

  public JoinFirework(Main plugin)
  {
  }

  private Color getColor(int i)
  {
    Color c = null;
    if (i == 1) {
      c = Color.AQUA;
    }
    if (i == 2) {
      c = Color.BLACK;
    }
    if (i == 3) {
      c = Color.BLUE;
    }
    if (i == 4) {
      c = Color.FUCHSIA;
    }
    if (i == 5) {
      c = Color.GRAY;
    }
    if (i == 6) {
      c = Color.GREEN;
    }
    if (i == 7) {
      c = Color.LIME;
    }
    if (i == 8) {
      c = Color.MAROON;
    }
    if (i == 9) {
      c = Color.NAVY;
    }
    if (i == 10) {
      c = Color.OLIVE;
    }
    if (i == 11) {
      c = Color.ORANGE;
    }
    if (i == 12) {
      c = Color.PURPLE;
    }
    if (i == 13) {
      c = Color.RED;
    }
    if (i == 14) {
      c = Color.SILVER;
    }
    if (i == 15) {
      c = Color.TEAL;
    }
    if (i == 16) {
      c = Color.WHITE;
    }
    if (i == 17) {
      c = Color.YELLOW;
    }
    return c;
  }
 
  @EventHandler
  public void onPlayerJoin(PlayerJoinEvent e)
  {
    if (this.i.intValue() == 0)
    {
      Player p = e.getPlayer();
      if (p.hasPermission("vipjoin.firework"))
      {
        Firework fw = (Firework)p.getWorld().spawnEntity(p.getLocation(), EntityType.FIREWORK);
        FireworkMeta fwm = fw.getFireworkMeta();
       
        Random r = new Random();
        int rt = r.nextInt(4) + 1;
       
        FireworkEffect.Type type = FireworkEffect.Type.BALL;
        if (rt == 1) {
          type = FireworkEffect.Type.BALL;
        }
        if (rt == 2) {
          type = FireworkEffect.Type.BALL_LARGE;
        }
        if (rt == 3) {
          type = FireworkEffect.Type.BURST;
        }
        if (rt == 4) {
          type = FireworkEffect.Type.CREEPER;
        }
        if (rt == 5) {
          type = FireworkEffect.Type.STAR;
        }
        int r1i = r.nextInt(17) + 1;
        int r2i = r.nextInt(17) + 1;
        Color c1 = getColor(r1i);
        Color c2 = getColor(r2i);
       
        FireworkEffect effect = FireworkEffect.builder().flicker(r.nextBoolean()).withColor(c1).withFade(c2).with(type).trail(r.nextBoolean()).build();
       
        fwm.addEffect(effect);
        fwm.setPower(1);
        fw.setFireworkMeta(fwm);
      }
    }
  }
}

 

@reboxer You're never spawning the firework. Just use spawnEntity for this. All of those if statements could be compressed using a switch statement. Why do you have an Integer object, and why not just use int?

 

Will 'i' ever have more than 1 value at the same time? No. so use a switch as @CodePlaysMinecraft said, or an if-else if-else block.
Have you gone through the basics of Java? If not, i advise you to do so because Bukkit development without Java knowledge = trouble & disaster.