Solved NullPointerException in my plugin.

Hello,

I'm trying to code a plugin where player data is accessed through a players.yml file. Before I run any data-pulling methods, I check if the configuration section corresponding to the player exists, so the code that pulls player data does not run if there is no section for the player.

I am coming across a NullPointerException on lines that should only run when the player data section exists. My YML file is blank.

Please see my error below

Code:

Caused by: java.lang.NullPointerException
at com.wyld.thimbleduels.ConfigManager.getPlayers(ConfigManager.java:27) ~[?:?]
at com.wyld.thimbleduels.GUIs.DuelsMenu.setItemMetas(DuelsMenu.java:68) ~[?:?]
at com.wyld.thimbleduels.GUIs.DuelsMenu.<init>(DuelsMenu.java:39) ~[?:?]
at com.wyld.thimbleduels.Commands.Thimble.onCommand(Thimble.java:19) ~[?:?]

Next, here is the method from which the error is coming:

Code:

    public void setItemMetas() {
        if(invite) {
            targetheadMeta = (SkullMeta) targethead.getItemMeta();
        }
        headMeta = (SkullMeta) head.getItemMeta();
        thimbleToggleMeta = thimbleToggle.getItemMeta();
        exitMeta = exit.getItemMeta();
        moneyMeta = money.getItemMeta();
        fillerMeta = filler.getItemMeta();
        headMeta.setOwningPlayer((OfflinePlayer) player);
        headMeta.setDisplayName(ChatColor.translateAlternateColorCodes('&', "&b&l" + player.getName()));
        if(cfgm.getPlayers().isConfigurationSection("Players." + player.getName())){
            played = cfgm.getPlayers().getInt("Players." + player.getName() + ".Played");
            wins = cfgm.getPlayers().getInt("Players." + player.getName() + ".Wins");
            losses = cfgm.getPlayers().getInt("Players." + player.getName() + ".Losses");
        }else {
            played = 0;
            wins = 0;
            losses = 0;
        }
        List<String> headLore = new ArrayList<String>();
        headLore.add(ChatColor.BLUE + "STATISTICS");
        headLore.add(ChatColor.BLUE + "Duels Played: " + ChatColor.DARK_GRAY + played);
        headLore.add(ChatColor.BLUE + "Duels Won: " + ChatColor.DARK_GRAY + wins);
        headLore.add(ChatColor.BLUE + "Duels Lost: " + ChatColor.DARK_GRAY + losses);
        // int winPercent = (wins/played)*100;
        //headLore.add(ChatColor.BLUE + "Win Percentage: " + ChatColor.DARK_GRAY + winPercent + "%");
        headMeta.setLore(headLore);
        head.setItemMeta(headMeta);
    
            
    }

Thanks in advance
wyld

 

It's line 68 that matters, it is

Code:

played = cfgm.getPlayers().getInt("Players." + player.getName() + ".Played");

 

It is because as a troubleshooting step, I got rid of the whole section surrounding line 68, and it worked fine (without that code of course)


This is ConfigManager.class, line 27 is marked in **********

Code:

package com.wyld.thimbleduels;

import org.bukkit.ChatColor;
import org.bukkit.configuration.file.FileConfiguration;
import com.wyld.thimbleduels.Configs.MapsCfg;
import com.wyld.thimbleduels.Configs.PlayersCfg;

public class ConfigManager {
    private ThimbleDuels plugin = ThimbleDuels.getPlugin(ThimbleDuels.class);
    private PlayersCfg players;
    private MapsCfg maps;
    public void loadConfigurationFiles() {
        if(!plugin.getDataFolder().exists()) {
            plugin.getDataFolder().mkdir();
            plugin.cmd.sendMessage(ChatColor.BLUE+ "Created the plugin data folder.");
        }
        players = new PlayersCfg();
        players.loadPlayers();
        maps = new MapsCfg();
      
    }
    public void saveConfigurationFiles() {
        players.savePlayers();
        //maps.saveMaps();
    }
    public FileConfiguration getPlayers() {
        return players.getPlayers(); **************
    }
    //public FileConfiguration getMaps() {
        //return maps.getMaps();
    //}
}

This is class DuelsMenu.class
Line 68 is marked in **********

Code:

package com.wyld.thimbleduels.GUIs;

import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Material;
import org.bukkit.OfflinePlayer;
import org.bukkit.entity.Player;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.meta.ItemMeta;
import org.bukkit.inventory.meta.SkullMeta;

import com.wyld.thimbleduels.ConfigManager;
import com.wyld.thimbleduels.VaultManager;
import com.wyld.thimbleduels.Configs.PlayersCfg;

public class DuelsMenu {
    private VaultManager vm = new VaultManager();
    private Inventory i;
    private ConfigManager cfgm = new ConfigManager();
    private Player player, target;
    private ItemStack head, targethead, thimbleToggle, exit, money, filler;
    private SkullMeta headMeta, targetheadMeta;
    private ItemMeta thimbleToggleMeta, exitMeta, moneyMeta, fillerMeta;
    private boolean invite;
    private int played, wins, losses;
    public DuelsMenu(Player player, Player target, boolean invite) {
        this.invite = invite;
        if(this.invite) {
        this.target = target;
        }
        this.player = player;
        i = Bukkit.createInventory(null, 18, ChatColor.BLUE + "ThimbleDuels");
        initializeItems();
        setItemMetas();
        addItems();
        player.openInventory(i);
    }
  
    public void initializeItems() {
        if(invite) {
            targethead = new ItemStack(Material.PLAYER_HEAD, 1);
        }
        head = new ItemStack(Material.PLAYER_HEAD, 1);
        thimbleToggle = new ItemStack(Material.RED_STAINED_GLASS_PANE, 1);
        exit = new ItemStack(Material.BARRIER, 1);
        money = new ItemStack(Material.GOLD_NUGGET, 1);
        filler = new ItemStack(Material.BLUE_STAINED_GLASS_PANE, 1);
    }

  
    public void setItemMetas() {
        if(invite) {
            targetheadMeta = (SkullMeta) targethead.getItemMeta();
        }
        headMeta = (SkullMeta) head.getItemMeta();
        thimbleToggleMeta = thimbleToggle.getItemMeta();
        exitMeta = exit.getItemMeta();
        moneyMeta = money.getItemMeta();
        fillerMeta = filler.getItemMeta();
        headMeta.setOwningPlayer((OfflinePlayer) player);
        headMeta.setDisplayName(ChatColor.translateAlternateColorCodes('&', "&b&l" + player.getName()));
        if(cfgm.getPlayers().isConfigurationSection("Players." + player.getName())){
            played = cfgm.getPlayers().getInt("Players." + player.getName() + ".Played"); ******************
            wins = cfgm.getPlayers().getInt("Players." + player.getName() + ".Wins");
            losses = cfgm.getPlayers().getInt("Players." + player.getName() + ".Losses");
        }else {
            played = 0;
            wins = 0;
            losses = 0;
        }
        List<String> headLore = new ArrayList<String>();
        headLore.add(ChatColor.BLUE + "STATISTICS");
        headLore.add(ChatColor.BLUE + "Duels Played: " + ChatColor.DARK_GRAY + played);
        headLore.add(ChatColor.BLUE + "Duels Won: " + ChatColor.DARK_GRAY + wins);
        headLore.add(ChatColor.BLUE + "Duels Lost: " + ChatColor.DARK_GRAY + losses);
        // int winPercent = (wins/played)*100;
        //headLore.add(ChatColor.BLUE + "Win Percentage: " + ChatColor.DARK_GRAY + winPercent + "%");
        headMeta.setLore(headLore);
        head.setItemMeta(headMeta);
      
              
    }
  
  
    public void addItems() {
        i.setItem(4, head);
    }
}

 

@wyld @wyld @wyld @wyld

Code:

package com.wyld.thimbleduels;

import org.bukkit.ChatColor;
import org.bukkit.command.ConsoleCommandSender;
import org.bukkit.plugin.java.JavaPlugin;

import com.wyld.thimbleduels.Commands.Thimble;

public class ThimbleDuels extends JavaPlugin{
    public ConsoleCommandSender cmd = this.getServer().getConsoleSender();
    ConfigManager cfgm;
    VaultManager vm;
    private boolean error = false;
    @Override
    public void onEnable() {
        loadConfigurationFiles();
        loadVault();
        register();
        if(!error) {
        cmd.sendMessage(ChatColor.GREEN + "ThimbleDuels has been successfully enabled.");
        }else {
            cmd.sendMessage(ChatColor.DARK_RED + "The plugin is disabling due to an error.");
            this.setEnabled(false);
        }
       
    }
   
    @Override
    public void onDisable() {
       
    }
   
    public void register() {
        getCommand("thimble").setExecutor(new Thimble());
    }
    public void loadConfigurationFiles() {
        cfgm = new ConfigManager();
        cfgm.loadConfigurationFiles();
        cfgm.saveConfigurationFiles();
    }
    public void loadVault() {
        vm = new VaultManager();
        if(vm.isVaultUsable()) {
            error = false;
        }else {
            cmd.sendMessage(ChatColor.DARK_RED + "It seems Vault is not installed, so ThimbleDuels cannot proceed with start-up.");
            error = true;
        }
       
    }
}

 

I figured it out, thanks!