Demande une note pour le serveur aux joueurs lorsqu'ils se connectent.

AskRating.java

package fr.skyost.rating;

import org.bukkit.Bukkit;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.PlayerJoinEvent;
import org.bukkit.plugin.java.JavaPlugin;

public class AskRating extends JavaPlugin implements Listener {
	
	@Override
	public final void onEnable() {
		try {
			Bukkit.getPluginManager().registerEvents(this, this);
		}
		catch(final Exception ex) {
			ex.printStackTrace();
		}
	}
	
	@EventHandler
	public final void onPlayerJoin(final PlayerJoinEvent event) {
		new Thread() {

			@Override
			public final void run() {
				int note = ServerRating.INVALID_RESPONSE;
				while(note == ServerRating.INVALID_RESPONSE) {
					note = new ServerRating(AskRating.this, event.getPlayer()).askRating();
				}
				Bukkit.getConsoleSender().sendMessage("Nouvelle note : " + note + "/5");
			}
			
		}.start();
	}
	
}

ServerRating.java

package fr.skyost.rating;

import java.util.concurrent.Callable;
import java.util.concurrent.Executors;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.EventPriority;
import org.bukkit.event.Listener;
import org.bukkit.event.player.AsyncPlayerChatEvent;
import org.bukkit.plugin.Plugin;

public class ServerRating implements Listener {
	
	public static final int INVALID_RESPONSE = -1;
	public static final int OTHER_ERROR = -2;
	
	private final Plugin plugin;
	private final Player player;
	
	private ValueCallable currentCallable;
	
	public ServerRating(final Plugin plugin, final Player player) {
		this.plugin = plugin;
		this.player = player;
	}
	
	public int askRating() {
		player.sendMessage(ChatColor.GOLD + "Veuillez noter notre serveur (sur 5) :");
		try {
			currentCallable = new ValueCallable();
			Bukkit.getPluginManager().registerEvents(this, plugin);
			final ValueCallableObject object = Executors.newFixedThreadPool(1).submit(currentCallable).get();
			if(object.exception != null) {
				throw new Exception(object.message, object.exception);
			}
			final int note = Integer.parseInt(object.message);
			if(note > 5) {
				throw new NumberFormatException();
			}
			AsyncPlayerChatEvent.getHandlerList().unregister(this);
			currentCallable = null;
			player.sendMessage(ChatColor.GREEN + "Merci !");
			return note;
		}
		catch(final NumberFormatException ex) {
			player.sendMessage(ChatColor.RED + "Nombre invalide !");
			return INVALID_RESPONSE;
		}
		catch(final Exception ex) {
			ex.printStackTrace();
			player.sendMessage(ChatColor.RED + "Une erreur est survenue pendant l'envoi de votre note : " + ex.getClass().getName());
			return OTHER_ERROR;
		}
	}

	@EventHandler(priority = EventPriority.LOWEST)
	public final void onAsyncPlayerChat(final AsyncPlayerChatEvent event) {
		currentCallable.setMessage(event.getMessage());
		event.setCancelled(true);
	}

	public class ValueCallable implements Callable<ValueCallableObject> {
			
		private String message;
		
		@Override
		public final ValueCallableObject call() {
			synchronized(this) {
				try {
					this.wait();
				}
				catch(final Exception ex) {
					return new ValueCallableObject(ex, "Une erreur est survenue pendant l'attente de la réponse.");
				}
				return new ValueCallableObject(null, message);
			}
		}
		
		public final String getMessage() {
			return message;
		}
		
		public final void setMessage(final String message) {
			synchronized(this) {
				this.message = message;
				this.notify();
			}
		}
		
	}

	public class ValueCallableObject {
		
		public final Throwable exception;
		private final String message;
		
		public ValueCallableObject(final Throwable exception, final String message) {
			this.exception = exception;
			this.message = message;
		}
		
	}
	
}