Essentials Hook isVanished() NullPointerException

Totally stuck here, I'm trying to run a check to see if a player is vanished using Essentials, but it's throwing a NullPointerException.

Main:

Code:

    private Essentials ess;

    public void onEnable() {
        ess = (Essentials) Bukkit.getServer().getPluginManager().getPlugin("Essentials");
      
        this.getServer().getPluginManager().registerEvents(new NotificationListener(this), this);
    }

Listener:

Code:

    @EventHandler
    public void onPlayerChangedWorld(PlayerChangedWorldEvent event) {
        for (Player notification : Bukkit.getOnlinePlayers()) {
            Player player = event.getPlayer();
            String playerName = player.getName();
            String world = player.getWorld().getName();
            if (!Main.toggleNotifications.contains(notification.getName())) {
                if (!Main.deafen.contains(notification.getName())) {
                    if (!ess.getUser(player).isVanished()) {
                        if (world.toLowerCase().startsWith("guest")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.WHITE + world);
                        } else if (world.toLowerCase().contains("member")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.GRAY + world);
                        } else if (world.toLowerCase().contains("recruit")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.GOLD + world);
                        } else if (world.toLowerCase().contains("builder")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.GREEN + world);
                        } else if (world.toLowerCase().contains("crafter")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.DARK_PURPLE + world);
                        } else if (world.toLowerCase().contains("operator")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.AQUA + world);
                        } else if (world.toLowerCase().contains("admin")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.BLUE + world);
                        } else if (world.toLowerCase().contains("owner")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.RED + world);
                        } else if (world.toLowerCase().contains("lobby")) {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + ChatColor.BLUE + world);
                        } else {
                            notification.sendMessage(ChatColor.YELLOW + playerName + " changed map to " + world);
                        }
                    }
                }
            }
        }
    }

Error:

Code:

[19:33:09] [Server thread/ERROR]: Could not pass event PlayerChangedWorldEvent to Opticore vComedic Kangaroo
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:297) ~[craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:501) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:486) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PlayerList.moveToWorld(PlayerList.java:561) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PlayerList.changeDimension(PlayerList.java:622) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.EntityPlayer.c(EntityPlayer.java:511) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.Entity.K(Entity.java:263) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.EntityLiving.K(EntityLiving.java:154) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.Entity.s_(Entity.java:230) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.EntityLiving.s_(EntityLiving.java:1396) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.EntityHuman.s_(EntityHuman.java:173) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.EntityPlayer.l(EntityPlayer.java:267) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PlayerConnection.a(PlayerConnection.java:353) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PacketPlayInFlying.a(SourceFile:126) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PacketPlayInPosition.a(SourceFile:57) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.PacketHandleTask.run(SourceFile:13) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_25]
    at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_25]
    at net.minecraft.server.v1_8_R1.MinecraftServer.z(MinecraftServer.java:643) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.DedicatedServer.z(DedicatedServer.java:284) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.MinecraftServer.y(MinecraftServer.java:598) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:506) [craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_25]
Caused by: java.lang.NullPointerException
    at net.dkcraft.opticore.listeners.NotificationListener.onPlayerChangedWorld(NotificationListener.java:69) ~[?:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_25]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_25]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_25]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:295) ~[craftbukkit-1.8-R0.1-SNAPSHOT.jar:git-Bukkit-7bc218d]
    ... 23 more

 

@xDeeKay

What is line 69 from your event?

 

@xize Sorry, should have clarified that, it's line 9 in the listener.

 

@xDeeKay

maybe try to use getUserMap() to see if the player first exists? and then try to use getUser(Player p) ?

I never used Essentials api but I did a quick view over this: https://github.com/essentials/Essen.../com/earth2me/essentials/Essentials.java#L701

 

Well this is the error, as you stated. A NullPointerException is when you reference a variable that is empty. The only variable on that line is player, so the player variable is null.

 

Make sure you have Essentials in the "depend" section of plugin.yml

 

@nverdier Close but not quite. A NullPointerException occurs when you dereference a null pointer, or a null reference if you will. I.e a reference pointing to null. This may be a variable but is not limited as such. A method call (e.g getUser) can return a null pointer. If you dereference that (.isVisible) you end up with a NullPointerException.

So to reiterate, the player variable may be null, but the error could also be that .getUser() returns null.

 

Dang it! Well thanks! Always thought it was a variable

 

@Rocoty So I need to check if the player exists like how @xize said?

 

@xDeeKay

Simply add a null check before you use the Player, and after you call for the result from Essentials.

 

@xDeeKay In this case, the ess variable may be a null reference, or getUser may return null. But the player variable isn't null due to the fact that the first stack trace element is on that line and you're not dereferencing player there.

Please post the whole listener class, so we can help you verify if ess is null.

EDIT: It would be fairly dumb if the player were null, to be fair. It is a player event after all.

 

Thanks guys, throwing in "if (essentials != null) {" did the trick!

 

@xDeeKay That sounds like it would remove the error, but not fix your problem. Are you sure your plugin is doing what it's supposed to do now?

 

@Rocoty I also does what it's supposed to, have I overlooked something though?

 

@xDeeKay I can't tell, as there is not enough context available for me to do so.

 

@Rocoty Then everything is fine, works the way I want with no errors, good enough for me!

 

The reason you probably needed that check is because your plugin loaded before essentials, which made ess null. As long as you add Essentials as a depend, should be fine.