제가 인벤토리 관련 코드를 작성했는데

제가 선택한 아이템일 경우 특정 동작을 취하고,

그 외 아이템일 경우 반환하는 식으로 코드를 짰습니다.

package shopgui.comsangbabo;

import net.md_5.bungee.api.chat.BaseComponent;
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Material;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.inventory.InventoryClickEvent;
import org.bukkit.inventory.ItemStack;

import java.util.Objects;

public class IronClick implements Listener {
    @EventHandler
    public void onClick(InventoryClickEvent event) {
        Player player = (Player) event.getWhoClicked();
        int min = 1;
        int max = 7;
        int randomAbl = (int) (Math.random() * (max - min)) + 1;

        if (Objects.requireNonNull(event.getCurrentItem()).getItemMeta().getDisplayName() == null) {
            return;
        } else if (Objects.requireNonNull(event.getCurrentItem()).getItemMeta().getDisplayName().equals(" ")) {
            event.setCancelled(true);
            return;
        } else if (Objects.requireNonNull(event.getCurrentItem()).getItemMeta().getDisplayName().equals(ChatColor.GRAY + "ㅎㅇ")) {
            event.setCancelled(true);
            return;
        } else if (Objects.requireNonNull(event.getCurrentItem()).getType() == null) {
            return;
        } else if (event.getCurrentItem() == null) {
            return;
        } else if (player.getInventory() == null) {
            return;
        }

        if (Objects.requireNonNull(event.getCurrentItem()).getItemMeta().getDisplayName().equals(ChatColor.GREEN + "" + ChatColor.BOLD + "추첨")) {
            if (player.getInventory().containsAtLeast(new ItemStack(Material.EMERALD_BLOCK), 1)) {
                if (randomAbl== 1) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.GOLD + "" + "L랭크 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "납치");

                    event.setCancelled(true);
                }

                else if (randomAbl == 2) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.LIGHT_PURPLE + "" + "S랭크 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "내성");

                    event.setCancelled(true);
                }

                else if (randomAbl == 3) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.GREEN + "" + "A랭크 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "도살자");

                    event.setCancelled(true);
                }

                else if (randomAbl == 4) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.BLUE + "" + "B랭크 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "동기화");

                    event.setCancelled(true);
                }

                else if (randomAbl == 5) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.GRAY + "" + "C랭크 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "구미호");

                    event.setCancelled(true);
                }

                else if (randomAbl == 6) {
                    player.getInventory().removeItem(new ItemStack(Material.EMERALD_BLOCK, 1));
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    player.sendMessage(ChatColor.DARK_RED + "" + "특수 능력이 뽑혔습니당 ㅎ" + ChatColor.WHITE + "!");
                    player.sendMessage(ChatColor.AQUA + "-----------");
                    Bukkit.getServer().dispatchCommand(Bukkit.getConsoleSender(), "aw util abi" + " " + player.getName() + " " + "공기");

                    event.setCancelled(true);
                }

                else {
                    player.sendMessage("111");
                    event.setCancelled(true);
                }
            } else {
                player.sendMessage(ChatColor.RED + "" + ChatColor.BOLD + "* 에메랄드 블록을 소지하고있지 않습니다!");
                event.setCancelled(true);
            }
        }
    }
}

위와 같은 코드를 작성한 결과,

서바이벌 모드 상태에서 인벤토리 내의 빈공간(Air)나 밖을 클릭할 시

Could not pass event InventoryClickEvent 라는 콘솔에러가 출력됩니다.

혹시 문제점을 알려주실분이 있나요?