KeepAlive.java

package de.cubeisland.KeepAlive;

import java.util.List;
import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;
import net.minecraft.server.EntityPlayer;
import net.minecraft.server.Packet0KeepAlive;
import net.minecraft.server.ServerConfigurationManager;
import org.bukkit.craftbukkit.CraftServer;
import org.bukkit.plugin.java.JavaPlugin;

public class KeepAlive extends JavaPlugin
{
    private Timer timer;

    @Override
    public void onEnable()
    {
        timer = new Timer("keepAliveTimer");
        timer.schedule(new KeepAliveTimer() , 5 * 1000, 5 * 1000);
    }

    @Override
    public void onDisable()
    {
        timer.cancel();
        timer = null;
    }

    private class KeepAliveTimer extends TimerTask
    {
        private final ServerConfigurationManager mojangServer;
        private final Random random;

        public KeepAliveTimer()
        {
            this.mojangServer = ((CraftServer)getServer()).getHandle();
            this.random = new Random();
        }

        @Override
        public void run()
        {
            for (EntityPlayer player : (List<EntityPlayer>)this.mojangServer.players)
            {
                player.netServerHandler.sendPacket(new Packet0KeepAlive(random.nextInt()));
            }
        }
    }
}