Hardcore Bedwars Plugin Class

package nightterror6.hardcorebedwars;

import org.bukkit.Bukkit;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;
import org.bukkit.scoreboard.DisplaySlot;
import org.bukkit.scoreboard.Objective;
import org.bukkit.scoreboard.Scoreboard;
import org.bukkit.scoreboard.ScoreboardManager;
import org.bukkit.scoreboard.Team;

import net.md_5.bungee.api.ChatColor;

public class Main extends JavaPlugin{

	public final String msgPrefix = "" + ChatColor.DARK_PURPLE + "[" + ChatColor.RED + "H" + ChatColor.BLUE +
			"B" + ChatColor.GREEN + "W" + ChatColor.DARK_PURPLE + "] ";

	private ScoreboardManager sm = Bukkit.getScoreboardManager();
	private Scoreboard b = sm.getNewScoreboard();
	private Team red, blue, green, yellow;
	private Objective kills = b.registerNewObjective("kills", "");

	@Override
	public void onEnable() {
		//Instantiate listeners
	}

	@Override
	public void onDisable(){

	}

	public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
		Player p = (Player) sender;
		if(command.getName().equalsIgnoreCase("hbw")) {

			if(args.length == 0 || args[0].equalsIgnoreCase("help")) {
				sender.sendMessage("" + ChatColor.AQUA + "Listing all commands for HardcoreBedwars: ");
				sender.sendMessage("" + ChatColor.GOLD + "start" + ChatColor.WHITE + ": " + ChatColor.RED + "Initialize the game");
				sender.sendMessage("" + ChatColor.GOLD + "join" + ChatColor.WHITE + ": " + ChatColor.RED + "Join the game");
			}
			else if(args[0].equalsIgnoreCase("start")) {

				kills.setDisplayName(ChatColor.GOLD + "Kills");
				kills.setDisplaySlot(DisplaySlot.SIDEBAR);

				red = b.registerNewTeam("red");
				blue = b.registerNewTeam("blue");
				green = b.registerNewTeam("green");
				yellow = b.registerNewTeam("yellow");

				red.setPrefix(ChatColor.DARK_RED + "[Red]");
				blue.setPrefix(ChatColor.BLUE + "[Blue]");
				green.setPrefix(ChatColor.DARK_GREEN + "[Green]");
				yellow.setPrefix(ChatColor.GOLD + "[Yellow]");

				red.setAllowFriendlyFire(false);
				blue.setAllowFriendlyFire(false);
				green.setAllowFriendlyFire(false);
				yellow.setAllowFriendlyFire(false);

				//Player[] ps = (Player[]) getServer().getOnlinePlayers().toArray();
				//for(int i = 0; i < ps.length; i++) {
				//	ps[i].setScoreboard(b);
				//}

				/*ArrayList<? extends Player> ps = (ArrayList<? extends Player>) getServer().getOnlinePlayers();
				Collections.shuffle(ps);

				for(int i = 0; i < ps.size(); i++) {
					if(i % 4 == 0) {
						red.addPlayer(ps.get(i));
					}
					else if(i % 4 == 1) {
						blue.addPlayer(ps.get(i));
					}
					else if(i % 4 == 2) {
						green.addPlayer(ps.get(i));
					}
					else if(i % 4 == 3) {
						yellow.addPlayer(ps.get(i));
					}
				}*/
			}
			else if(args[0].equalsIgnoreCase("join")) {
				p.setScoreboard(b);
			}

		}

		return false;
	}
}