Solved Cannot set scoreboard for invalid CraftPlayer?

Hello Bukkit, I randomly get this error when I try to set a scoreboard to a player. When the server starts, I could join for the first time, and everything will work. But if I were to leave and join back, an error happens. Am I doing something wrong here?

Code:java

 @EventHandler
public void onPlayerJoin(PlayerJoinEvent event){
Player player = event.getPlayer();
Scoreboards.getInstance().update(player);
}
 
 
public void update(Player player){
ScoreboardManager manager = Bukkit.getScoreboardManager();
Scoreboard board = manager.getNewScoreboard();
Objective o = board.registerNewObjective(player.getName(), "dummy");
o.setDisplaySlot(DisplaySlot.SIDEBAR);
o.setDisplayName(ChatColor.GOLD + "Stats ");
Score s = o.getScore(Bukkit.getOfflinePlayer("Player"));
s.setScore(1);
player.setScoreboard(board);
}

Error:

PHP:

[15:07:03 INFO]: thepaperboy99[/127.0.0.1:57638] logged in with entity id 608 at
([world] 84.02248098741508, 70.0, 260.69999998807907)
[15:07:03 ERROR]: Could not pass event PlayerJoinEvent to KitPvP v0.1
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:427) ~[craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.jav
a:62) ~[craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.j
ava:481) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.j
ava:466) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PlayerList.c(PlayerList.java:225) [craft
bukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.PlayerList.a(PlayerList.java:116) [craft
bukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.LoginListener.c(LoginListener.java:78) [
craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.LoginListener.a(LoginListener.java:42) [
craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:149
) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134) [craf
tbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:6
55) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:2
50) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:5
45) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java
:457) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:6
17) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
Caused by: java.lang.IllegalStateException: Cannot set scoreboard for invalid Cr
aftPlayer
        at org.bukkit.craftbukkit.v1_7_R1.entity.CraftPlayer.setScoreboard(Craft
Player.java:1063) ~[craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        at me.thepaperboy99.kitpvp.Scoreboards.update(Scoreboards.java:33) ~[?:?
]
        at me.thepaperboy99.kitpvp.KitPVPListener.onPlayerJoin(KitPVPListener.ja
va:18) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.6.0
_05]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.6.0
_05]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1
.6.0_05]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.6.0_05]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.ja
va:425) ~[craftbukkit.jar:git-Bukkit-1.7.2-R0.2-b2974jnks]
        ... 14 more

Line 33 is player.setScoreboard(board);

All help is appreciated, Thanks!

 

If you look at the source for CraftPlayer you'll this see under setScoreboard:

Code:java

 if (playerConnection.isDisconnected()) {
throw new IllegalStateException("Cannot set scoreboard for invalid CraftPlayer");
}
 

I vaguely remember this problem from some of my other plugins. I'm not entirely sure, but I think PlayerJoinEvent is fired before the Player is set to connected (I might be completely wrong). First, try setting your priority to Monitor, which probably won't work. If that doesn't work, try scheduling the code for one tick after the PlayerJoinEvent.

 

Thanks, I figured a scheduler would work half an hour after I posed lol. But thanks anyways.