getWorld form offline player

Hey,

i needed a plugin that would show me the current world for all offline players (who were previously on the server). This will probably only be possible with nbt (because Bukkit of type getOfflinePlayers cannot query a current world). Not individually but for all in world/playerdata (for over 100).

I tried this, but unfortunately it didn't work.

Code:

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.World;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.command.TabCompleter;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;

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

public class Main extends JavaPlugin {

    @Override
    public void onEnable() {
        // Plugin-Aktivierung
    }

    @Override
    public void onDisable() {
        // Plugin-Deaktivierung
    }

    @Override
    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
        if (command.getName().equalsIgnoreCase("offlineplayers")) {
            List<String> offlinePlayerList = new ArrayList<>();

            for (OfflinePlayer offlinePlayer : Bukkit.getOfflinePlayers()) {
                if (isOffline(offlinePlayer)) {
                    offlinePlayerList.add(offlinePlayer.getName());
                }
            }

            if (offlinePlayerList.isEmpty()) {
                sender.sendMessage(ChatColor.RED + "Es sind keine Offline-Spieler verfügbar.");
            } else {
                sender.sendMessage(ChatColor.GREEN + "Liste der Offline-Spieler:");
                for (String playerName : offlinePlayerList) {
                    String worldName = getOfflinePlayerWorld(playerName);
                    sender.sendMessage(ChatColor.YELLOW + playerName + " ist/war in der Welt: " + worldName);
                }
            }

            return true;
        }

        return false;
    }

    private boolean isOffline(OfflinePlayer player) {
        return !player.isOnline();
    }

    private String getOfflinePlayerWorld(String playerName) {
        OfflinePlayer offlinePlayer = Bukkit.getOfflinePlayer(playerName);
        UUID playerId = offlinePlayer.getUniqueId();

        for (World world : Bukkit.getWorlds()) {
            if (world.getPlayers().stream().anyMatch(player -> player.getUniqueId().equals(playerId))) {
                return world.getName();
            }
        }

        return ChatColor.RED + "Unbekannte Welt";
    }
}

 

Unfortunately I have to change the plugin for separate inventories per world and I want to find out beforehand who is still on a certain world (to inform him if necessary, otherwise the inventory will be lost).

 

Mh that's an idea, but there are over 700 files which I would then have to search through.

 

So I would prefer "not" to remove it. But unfortunately there is no one to update it. There are hardly any good alternatives.

Plugin:
https://github.com/EbonJaeger/perworldinventory-kt

 

I have been getting these errors since 1.20.2:

Code:

[15:48:50 INFO]: [ACF] Can't read players locale, you will be unable to automatically detect players language. Only Bukkit 1.7+ is supported for this.
[15:48:50 INFO]: [ACF] java.lang.NoSuchFieldException: locale

[15:48:50 INFO]: [ACF]    at java.base/java.lang.Class.getDeclaredField(Class.java:2642)

[15:48:50 INFO]: [ACF]    at perworldinventory-kt-2.3.2.jar//me.ebonjaeger.perworldinventory.command.acf.BukkitCommandManager.readPlayerLocale(BukkitCommandManager.java:313)

[15:48:50 INFO]: [ACF]    at perworldinventory-kt-2.3.2.jar//me.ebonjaeger.perworldinventory.command.acf.ACFBukkitListener.onPlayerJoin(ACFBukkitListener.java:54)

[15:48:50 INFO]: [ACF]    at com.destroystokyo.paper.event.executor.MethodHandleEventExecutor.execute(MethodHandleEventExecutor.java:40)

[15:48:50 INFO]: [ACF]    at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:81)

[15:48:50 INFO]: [ACF]    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70)

[15:48:50 INFO]: [ACF]    at io.papermc.paper.plugin.manager.PaperEventManager.callEvent(PaperEventManager.java:54)

[15:48:50 INFO]: [ACF]    at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.callEvent(PaperPluginManagerImpl.java:126)

[15:48:50 INFO]: [ACF]    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:615)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.players.PlayerList.a(PlayerList.java:325)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.network.ServerConfigurationPacketListenerImpl.a(ServerConfigurationPacketListenerImpl.java:130)

[15:48:50 INFO]: [ACF]    at net.minecraft.network.protocol.configuration.ServerboundFinishConfigurationPacket.a(ServerboundFinishConfigurationPacket.java:18)

[15:48:50 INFO]: [ACF]    at net.minecraft.network.protocol.configuration.ServerboundFinishConfigurationPacket.a(ServerboundFinishConfigurationPacket.java:9)

[15:48:50 INFO]: [ACF]    at net.minecraft.network.protocol.PlayerConnectionUtils.lambda$ensureRunningOnSameThread$0(PlayerConnectionUtils.java:53)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.TickTask.run(TickTask.java:18)

[15:48:50 INFO]: [ACF]    at net.minecraft.util.thread.IAsyncTaskHandler.d(IAsyncTaskHandler.java:153)

[15:48:50 INFO]: [ACF]    at net.minecraft.util.thread.IAsyncTaskHandlerReentrant.d(IAsyncTaskHandlerReentrant.java:24)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.b(MinecraftServer.java:1324)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.d(MinecraftServer.java:193)

[15:48:50 INFO]: [ACF]    at net.minecraft.util.thread.IAsyncTaskHandler.x(IAsyncTaskHandler.java:126)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.bg(MinecraftServer.java:1301)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.x(MinecraftServer.java:1294)

[15:48:50 INFO]: [ACF]    at net.minecraft.util.thread.IAsyncTaskHandler.bp(IAsyncTaskHandler.java:114)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:1410)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:1156)

[15:48:50 INFO]: [ACF]    at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:315)

[15:48:50 INFO]: [ACF]    at java.base/java.lang.Thread.run(Thread.java:833)

In addition, Paper Timings will be removed very soon:

Code:

[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Commands' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 INFO]: [ACF] Enabled Asynchronous Tab Completion Support!
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory help' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory version' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory reload' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory convert' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group create' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group addworld' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group info' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group list' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group delete' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group removeworld' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory group setrespawn' - this is deprecated behavior, please report it to the authors: EbonJaeger
[15:45:36 WARN]: Plugin 'PerWorldInventory' is creating timing 'Command: perworldinventory migrate' - this is deprecated behavior, please report it to the authors: EbonJaeger

But it still seems to work. Maybe it's just small things.

 

There are only a few commits from the github dependabot in the fork.
I also tried to compile the fork, the result was 21 errors.

 

You could just save player world locations in a big UUID hashmap, and save it to file when the server stops. (auto saving every once in a while would be a good idea as well in case of crashes)

 

Do you have a suggestion for the code?

 

I don't have my pc right now, but it should be as simple as adding a playerquitevent, and saving/loading the hashmap from disk, which is pretty simple with .yml files. Just store world names with UUID as the key. To autosave make a repeating bukkit runnable.

 

I don't think you've fully understood the problem. I meant offline players who are not online and have not been online for a long time. Saving the data for the future is not what I meant.

 

Their locations is stored in the world files. In worst case you can make a Python script to extract that data and convert it to the yml file. All future cases can be handled by the plugin.

Edit: it's pretty strange that this huge API doesn't have a function for offline players to see where they've logged off. So either do the Python thing or integrate the world files reading right into your plugin.

 

It is also incomprehensible to me why there is nothing for this in the API. Unfortunately, I don't know how to convert the player data (nbt) into a yml.

 

To tell players to come online and change the world. There are several ways to contact players (mail, discord etc).

There are certainly several reasons to request the location of offline players other than multiple inventories.

 

I am sure that there are other reasons than multiple inventories.

 

For the general problem, I think this advice is best:

And for this:

I would recommend some small script (python?) to iterate over the files and extract the data you need.

For the more specific question though, of "what world did an OfflinePlayer log out in", the only way I know to do it is by reading the .dat files, in <server dir>/<world>/playerdata/<uuid>.dat

These files can be opened by external MC-editor tools, but technically can also be accessed in Bukkit API:

Code:

Player player;
player.saveData(); // Saves to <world>/playerdata/<uuid>.dat
player.loadData(); // Loads from <world>/playerdata/<uuid>.dat

These are run automatically when a player joins/disconnects.

So if you wanted, you could rename a .dat file to your own account's UUID, and load someone else's data, which includes the world they logged out in in... I don't really want to recommend this as a "solution" since it is very easy to accidentally overwrite or lose data for any accounts involved, but it's technically an option.

I've used it before for viewing offline inventories, the code is a bit dense, but you can view it here if curious.

 

Just access the player's persistent data container every time they switch worlds and store the world name they switched to in the container as a NamespacedKey. Whenever they leave the server, you can just access this NamespacedKey again to check what world they were in last.

Or, can you not just do player.getWorld() whenever they leave the server? The event triggers just before they leave, does it not?

Code:

//when they switch worlds
PersistentDataContainer container = player.getPersistentDataContainer();
NamespacedKey world = new NamespacedKey(plugin, "World");
container.set(world, PersistentDataType.STRING, p.getWorld().getName());

//when they leave the server
PersistentDataContainer container = player.getPersistentDataContainer();
NamespacedKey world = new NamespacedKey(plugin, "World");
String world = container.get(world, PersistentDataType.STRING);

 

I have now done the same. Notepad++ can, for example, search for content in many yml files.

However, I would like to have a simple query by command.