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// 
// EVENT
//

public class EventClick implements Listener {

    @EventHandler
    public void onInventoryClick(InventoryClickEvent e) {
        if(e.getView().getTitle().equalsIgnoreCase(ChatColor.AQUA + "Custom GUI")) {

            Player player = (Player) e.getWhoClicked();

            switch(e.getCurrentItem().getType()) {
                case TNT:
                    player.closeInventory();
                    player.setHealth(0.0);
                    player.sendMessage("Zabiłeś się! Brawo.");
                    break;
                case BREAD:
                    player.closeInventory();
                    player.setFoodLevel(20);
                    player.sendMessage("Jummy");
                    break;
                case GOLDEN_SWORD:
                    player.closeInventory();
                    player.getInventory().addItem(new ItemStack(Material.GOLDEN_SWORD));
                    player.sendMessage("Miecz");
                    break;
            }

            e.setCancelled(true);
        }
    }

}

//
// TWORZENIE GUI
//

@Override
public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {

    if(sender instanceof Player) {

        Player player = (Player) sender;
        Inventory gui = Bukkit.createInventory(player, 9, ChatColor.AQUA + "Custom GUI");

        ItemStack suicide = new ItemStack(Material.TNT);
        ItemStack feed = new ItemStack(Material.BREAD);
        ItemStack sword = new ItemStack(Material.GOLDEN_SWORD);
        ItemStack[] menuItems = {suicide, feed, sword};

        ItemMeta suicideMeta = suicide.getItemMeta();
        suicideMeta.setDisplayName(ChatColor.RED + "Suicide");
        ArrayList<String> suicideLore = new ArrayList<>();
        suicideLore.add(ChatColor.GOLD + "Kill yourself");
        suicideMeta.setLore(suicideLore);
        suicide.setItemMeta(suicideMeta);

        ItemMeta feedMeta = feed.getItemMeta();
        feedMeta.setDisplayName(ChatColor.GREEN + "Feed");
        ArrayList<String> feedLore = new ArrayList<>();
        feedLore.add(ChatColor.GOLD + "Feed yourself");
        feedMeta.setLore(feedLore);
        feed.setItemMeta(feedMeta);

        ItemMeta swordMeta = sword.getItemMeta();
        swordMeta.setDisplayName(ChatColor.BLUE + "Sword");
        ArrayList<String> swordLore = new ArrayList<>();
        swordLore.add(ChatColor.GOLD + "Give a sword");
        swordMeta.setLore(swordLore);
        sword.setItemMeta(swordMeta);
        
        gui.setContents(menuItems);

        player.openInventory(gui);
        System.out.println();
    }

    return true;
}