Solved NullPointerException

Hi bukkit users!

I have this piece of code:

Code:

    JavaPlugin plugin;
        public ChestEvents(MoneyChest plugin) {
        this.plugin = plugin;
        }

and this in my onEnable():

Code:

        Listener ChestEventsListener = new ChestEvents(this);
        Bukkit.getServer().getPluginManager().registerEvents(ChestEventsListener, this);

This is the problem, every time I use "plugin." the console throws a NPE:

Code:

[11:41:34 ERROR]: Error occurred while enabling MoneyChest v0.1 (Is it up to dat
e?)
java.lang.NullPointerException
        at me.amatokus8669.plugin.moneychest.ChestEvents.<init>(ChestEvents.java
:42) ~[?:?]
        at me.amatokus8669.plugin.moneychest.MoneyChest.onEnable(MoneyChest.java
:50) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316) ~[c
raftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader
.java:324) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManage
r.java:404) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.craftbukkit.v1_7_R3.CraftServer.loadPlugin(CraftServer.jav
a:446) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.craftbukkit.v1_7_R3.CraftServer.enablePlugins(CraftServer.
java:380) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.craftbukkit.v1_7_R3.CraftServer.reload(CraftServer.java:79
9) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.Bukkit.reload(Bukkit.java:288) [craftbukkit.jar:git-Bukkit
-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:
23) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:18
0) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.craftbukkit.v1_7_R3.CraftServer.dispatchCommand(CraftServe
r.java:701) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at org.bukkit.craftbukkit.v1_7_R3.CraftServer.dispatchServerCommand(Craf
tServer.java:688) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at net.minecraft.server.v1_7_R3.DedicatedServer.aB(DedicatedServer.java:
296) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at net.minecraft.server.v1_7_R3.DedicatedServer.v(DedicatedServer.java:2
61) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at net.minecraft.server.v1_7_R3.MinecraftServer.u(MinecraftServer.java:5
58) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java
:469) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]
        at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:6
28) [craftbukkit.jar:git-Bukkit-1.7.9-R0.1-9-gaceeb44-b3091jnks]

Thanks

 

Err we can see a very limited piece of code, a litle more please...

 

My main class onEnable():

Code:

    public void onEnable(){
        chests = new ArrayList<String>();
        LF = new LocationFiles(this);
         getLogger().info("=============================================");
         getLogger().info("If this is your first time using this plugin:");
         getLogger().info("Please configure the plugin.");
         getLogger().info("=============================================");
        Listener ChestEventsListener = new ChestEvents(this);
        Bukkit.getServer().getPluginManager().registerEvents(ChestEventsListener, this);
        Bukkit.getServer().getPluginManager().registerEvents(this, this);
        this.saveDefaultConfig();       
        
        if (!setupEconomy()) {
            log.severe(String.format("[%s] - Economy Disabled due to no Vault dependency found!",getDescription().getName()));
            return;
        }else{
            ecoworks = true;
        }
       
       
        try {
            cfile.load(file);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (InvalidConfigurationException e) {
            e.printStackTrace();
        }
       
        if(cfile.getList("money_chests") != null){
        for(int l=0; l==cfile.getList("money_chests").size(); l++){
            String location = cfile.getList("money_chests").get(l).toString();
            Location loc = LF.LoadLocationFile(location);
            if(loc != null){
            Bukkit.getServer().getScheduler().scheduleSyncRepeatingTask(this, new Runnable(){
                @Override
                public void run() {
                loc.getWorld().playEffect(loc, Effect.ENDER_SIGNAL, 10);
                }
            },20, 40);
        }
        }
        }else{
            cfile.addDefault("money_chests", chests);
        }
    }

My secondary class:

Code:

package me.amatokus8669.plugin.moneychest;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.block.Block;
import org.bukkit.configuration.file.FileConfiguration;
import org.bukkit.configuration.file.YamlConfiguration;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.block.BlockBreakEvent;
import org.bukkit.event.inventory.InventoryCloseEvent;
import org.bukkit.event.inventory.InventoryType;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.event.world.WorldLoadEvent;
import org.bukkit.inventory.DoubleChestInventory;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.bukkit.plugin.Plugin;
import org.bukkit.plugin.java.JavaPlugin;



public class ChestEvents implements Listener {
   
   
    LocationFiles LF;
    JavaPlugin plugin;
        public ChestEvents(MoneyChest plugin) {
        this.plugin = plugin;
        LF = new LocationFiles(plugin);
        }
       

   
    public File file = new File(plugin.getDataFolder()+File.separator+"Chests"+File.separator+"chests.yml");
    public FileConfiguration cfile = YamlConfiguration.loadConfiguration(file);
   
    String currency = plugin.getConfig().getString("currency");
    HashMap<String, Integer> solditemsmap = new HashMap<String, Integer>();
    ArrayList<String> solditems = new ArrayList<String>();
    Double totalprice = 0.0;
    private String material;
    private Integer quantity;
    private Double itemprice;
    String announcement = ChatColor.BOLD+""+ChatColor.GOLD+"["+ChatColor.YELLOW+"Money Chest"+ChatColor.GOLD+"]"+ChatColor.RESET+": ";
    @SuppressWarnings("deprecation")
   
    @EventHandler
    public void onChestOpenEvent(PlayerInteractEvent event){
        if(event.getAction().equals(Action.RIGHT_CLICK_BLOCK)){
        Player player = plugin.getServer().getPlayer(event.getPlayer().getName().toString());
        player.sendMessage("event works");
        Block block = event.getPlayer().getTargetBlock(null, 100);
        if(event.getPlayer().hasPermission("moneychest.use")){
            player.sendMessage("has permission");
            if(block.getType().equals(Material.CHEST)){
                event.setCancelled(true);
                player.sendMessage("is chest");
                if(LF.isDoubleChest(block) == true){
                    player.sendMessage("is double chest");
                    Location loc = LF.getDoubleChestLocation(block);
                    if(cfile.getList("money_chests").contains(loc)){
                        player.sendMessage("is in chest list");
                        Inventory inventory = Bukkit.createInventory(event.getPlayer(), 54, "Money chest");
                    player.openInventory(inventory);
                    }
                }else{
                    player.sendMessage("is single chest");
                    Location loc = block.getLocation();
                    if(cfile.getList("money_chests").contains(loc)){
                        player.sendMessage("is in chest list");
                        Inventory inventory = Bukkit.createInventory(event.getPlayer(), 27, "Money chest");
                    player.openInventory(inventory);
                    }
                }
            }
        }else{
            event.setCancelled(true);
            player.sendMessage(announcement + "You are not allowed to open this chest.");
            }
        }
    }
   
    @EventHandler
    public void onChestCloseEvent(InventoryCloseEvent event){
        Player player = plugin.getServer().getPlayer(event.getPlayer().getName());
        Block block = event.getPlayer().getTargetBlock(null, 100);
        player.sendMessage("0");
        if(event.getInventory() instanceof DoubleChestInventory || event.getInventory().getType().equals(InventoryType.CHEST)){
            String chestlocation = null;
            player.sendMessage("1");
            if(LF.isDoubleChest(block)){
                player.sendMessage("2");
            chestlocation = LF.getDoubleChestLocation(block).toString();
            }else{
                player.sendMessage("3");
            chestlocation = block.getLocation().toString();
            }
            player.sendMessage("4");
            player.sendMessage(chestlocation);
            if(cfile.getList("money_chests").contains(chestlocation)){
                player.sendMessage("5");
                if(event.getInventory().getContents().length!=0){
                    player.sendMessage("6");
                    for(int s=0; s<event.getInventory().getSize(); s++){
                        player.sendMessage("7");
                        if(event.getInventory().getItem(s)!=null){
                            player.sendMessage("8");
                            ItemStack item = event.getInventory().getItem(s);
                            material = item.getType().toString();
                            quantity = item.getAmount();
                            itemprice = plugin.getConfig().getDouble(material);
                            if(solditems.contains(material)){
                                player.sendMessage("9");
                                solditemsmap.replace(material, solditemsmap.get(material)+quantity);
                            }else{
                                player.sendMessage("10");
                                solditemsmap.put(material, quantity);
                                solditems.add(material);
                            }
                            totalprice = totalprice + itemprice;
                        }
                    }

                    if(quantity!=null && material!=null && itemprice!=null){
                        player.sendMessage("11");
                        Integer itemsamount = solditemsmap.size();
                        for(int i=0; i<itemsamount; i++){
                            player.sendMessage("12");
                            String mat = solditems.get(i);
                            Integer qua = solditemsmap.get(mat);
                            Double pri = plugin.getConfig().getDouble(mat);
                            player.sendMessage(announcement+ChatColor.GOLD+ChatColor.BOLD+pri*qua+ChatColor.GREEN+": "+ChatColor.RESET+ChatColor.GREEN+"(x"+ChatColor.GOLD+qua+" "+mat+ChatColor.GREEN+")");
                        }
                        MoneyChest.econ.depositPlayer(event.getPlayer().getName(), totalprice);
                        player.sendMessage(announcement+ChatColor.GOLD+ChatColor.BOLD+totalprice+ChatColor.DARK_GREEN+": (Total)");
                        totalprice = 0.0;
                        event.getInventory().clear();
                        solditemsmap.clear();
                        solditems.clear();
                        material = null;
                        quantity = null;
                        itemprice = null;
                    }
                }
            }
        }
        }
    @EventHandler
    public void onChestBreakEvent(BlockBreakEvent event){
        Block block = event.getBlock();
        String loc = null;
        if(LF.isDoubleChest(block)){
            loc = LF.getDoubleChestLocation(block).toString();
        }else{
            loc = block.getLocation().toString();
        }
        if(cfile.getList("money_chests").contains(loc)){
            if(event.getPlayer().hasPermission("moneychest.break")){
            MoneyChest.chests.remove(loc);
            cfile.set("money_chests", MoneyChest.chests);
            event.getPlayer().sendMessage(announcement+"Money chest removed.");
        }else{
            event.setCancelled(true);
        }
    }
    }
}

@mine-care

 

@amatokus

Code:

at me.amatokus8669.plugin.moneychest.ChestEvents.<init>(ChestEvents.java
:42) ~[?:?]
        at me.amatokus8669.plugin.moneychest.MoneyChest.onEnable(MoneyChest.java
:50) ~[?:?]

May you show us Line 50 of MoneyChest?

 

Code:

public File file = new File(plugin.getDataFolder()+File.separator+"Chests"+File.separator+"chests.yml");

Fields are initialized before constructor is run, and you are trying to use field "plugin" here, before you initialize it in constructor.

This piece of error is a hint

Code:

at me.amatokus8669.plugin.moneychest.ChestEvents.<init>(ChestEvents.java :42)

 

@SuperSniper

Code:

        Listener ChestEventsListener = new ChestEvents(this);

@raGan. What do you mean?

 

I think that they are initialised in the constructor but on the top part, static are the ones to be initialised upon class loading.
But still if the instance is initialised after the field then it wil throw an npe
@amatokus

 

@amatokus
He means that you are calling the plugin variable before the plugin variable has been set.

You must define the file within onEnable

 

Thanks, solved.