[Resource] Dynamic Signwall

I made this class to show how easy it is to create one of those fancy dynamic sign-walls that servers like Hypixel, Armadacraft and MineCade (last 2 are basically the same) are having. I added comments to explain what I'm doing in every method. The only thing you have to do is create a GameInstance class that represents an instance of your minigame. Feel free to modify or give me some constructive criticism!

Code:java

import org.bukkit.block.Sign;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.plugin.java.JavaPlugin;
import org.bukkit.scheduler.BukkitRunnable;
 
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Queue;
 
/**
 * User: Ivan
 * Date: 24/08/13
 * Time: 0:05
 * IDE: IntelliJ IDEA
 * Look me up on bukkit forums!
 * [url]http://forums.bukkit.org/members/ivan.5352/[/url]
 */
public class SignWall extends BukkitRunnable implements Listener {
 
    HashMap<Sign,GameInstance> signpool = new HashMap();
    Queue<GameInstance> gamequeue = new LinkedList<GameInstance>();
    JavaPlugin plugin;
 
 
    /*
    The constructor fills our signpool up with sig schedules a
    new bukkit task and registers the associated listener for us.
     */
    public SignWall(Sign[] signs,JavaPlugin plugin){
        for(Sign sign:signs)
            signpool.put(sign,null);
 
        this.plugin = plugin;
        this.runTaskTimer(plugin, 0, 20L);
        plugin.getServer().getPluginManager().registerEvents(this, plugin);
    }
 
    /*
    Gets an empty sign out of our signpool
     */
    public Sign getEmptySign(){
        for(Sign sign:signpool.keySet()){
            if(signpool.get(sign) == null)
                return sign;
        }
 
        return null;
    }
 
    /*
    This will be used by the listener that will check
    if there is a game associated with the clicked sign.
     */
    public GameInstance getBySign(Sign sign){
        return signpool.get(sign);
    }
 
    /*
    This method will be called by your gameinstance
    or by some kind of handler that decides when
    a game should show up here on the signwall
    */
    public void addToQueue(GameInstance instance){
        gamequeue.offer(instance);
    }
 
    /*
    This is the method called by our loop
    that will decide what pops up when
    the sign is empty.
     */
    private void formatEmptySign(Sign sign){
        sign.setLine(0,"------------");
        sign.setLine(1,"  Waiting   ");
        sign.setLine(3,"------------");
    }
 
    /*
    This is our loop. Here is where the magic
    happens :).
     */
    @Override
    public void run() {
 
 
    /* This part removes full games from the signwall,
     since they don't need players anymore*/
        for(Sign sign:signpool.keySet()){
            GameInstance instance = signpool.get(sign);
 
           /* If it no longer needs players,
           remove it from the board*/
            if(!instance.needsPlayers()){
                signpool.put(sign,null);
                formatEmptySign(sign);
                sign.update();
            }
        }
 
 
     /* This part checks if more games have to be added to the list
      */
        while(!gamequeue.isEmpty()){
            Sign emptysign = getEmptySign();
 
           /* If no signs are availible, break out of the loop
            */
            if(emptysign == null)
                break;
 
            GameInstance instance = gamequeue.poll();
            instance.formatSign(emptysign);
            emptysign.update();
            signpool.put(emptysign, instance);
 
        }
 
    }
 
    /*
    This is the listener part of our controller.
    It checks if a game is associated with the
    clicked sign.
     */
    @EventHandler
    public void onJoinAttempt(PlayerInteractEvent event){
        if(event.getPlayer().getWorld().getName().equalsIgnoreCase("lobby") &&
                event.getAction() == Action.RIGHT_CLICK_BLOCK &&
                event.getClickedBlock().getState() instanceof Sign){
 
            GameInstance instance = getBySign((Sign) event.getClickedBlock().getState());
 
            /* If there is a game associated, tell the gameinstance
            that someone is trying to join. It will return us a
            string with the message that the player will receive.
            If there is still a spot left for him, the instance
            can teleport him using the joinAttempt() method.
             */
            if(instance != null)
                event.getPlayer().sendMessage(instance.joinAttempt(event.getPlayer()));
        }
    }
}
 

 

Except it lack's Armadacraft's sorting method I put blood, sweat, and tears into

 

Awesome tutorial Ivan, I know quite a few people want to learn how to do this.

 

If I remember right it's more efficient to check the type of the block than get its state and check if it's a sign. Not positive, though.