Resource Creating Personalized Scoreboards

About
Creating personalized scoreboards (per-player) can be difficult if not done correctly. This tutorial will show you how to not only create a scoreboard that displays the player's stats but also how to prevent flickering.

Note: I prefer using the section sign (§) for color codes over ChatColor.COLOR, sorry if this bothers you!

Code
(All sections will be in a spoiler named according to their classes)

Spoiler: Main.Java

Code (Java):

public class Main extends JavaPlugin {

    @Override
    public void onEnable() {
        this.getServer().getPluginManager().registerEvents(new PlayerJoin(), this);
        this.getServer().getPluginManager().registerEvents(new PlayerLeave(), this);

        sbmanager.start();
    }

}

Spoiler: ScoreboardManager.java

Code (Java):

public class ScoreboardManager {

    private final MapHandler map = new MapHandler();
    private final Main plugin = new Main();

    public void createScoreboard(Player player) {
        Scoreboard scoreboard = Bukkit.getScoreboardManager().getNewScoreboard();
        Objective objective = scoreboard.registerNewObjective("§bTest", "dummy");
        objective.setDisplaySlot(DisplaySlot.SIDEBAR);

        map.addPlayerScoreboard(player, scoreboard);

        Score blankLine = objective.getScore("§0");
        blankLine.setScore(15);

        if (scoreboard.getTeam("name") == null) {
            scoreboard.registerNewTeam("name");
        }
        scoreboard.getTeam("name").addEntry("§7");
        scoreboard.getTeam("name").setPrefix("§fName: §7");
        scoreboard.getTeam("name").setSuffix(player.getName());
        objective.getScore("§7").setScore(14);

        if (scoreboard.getTeam("health") == null) {
            scoreboard.registerNewTeam("health");
        }
        scoreboard.getTeam("health").addEntry("§7§7");
        scoreboard.getTeam("health").setPrefix("§fHealth: §7");
        scoreboard.getTeam("health").setSuffix("" + player.getHealth());
        objective.getScore("§7§7").setScore(13);

        map.addOnlinePlayer(player);
        player.setScoreboard(scoreboard);
    }

    public void updateScoreboards() {
        for (Player player : Bukkit.getOnlinePlayers()) {

            Scoreboard scoreboard = map.getPlayerScoreboard(player);

            if (scoreboard.getTeam("name") == null) {
                scoreboard.registerNewTeam("name");
            }
            scoreboard.getTeam("name").setPrefix("§fName: §7");
            scoreboard.getTeam("name").setSuffix(player.getName());

            if (scoreboard.getTeam("health") == null) {
                scoreboard.registerNewTeam("health");
            }
            scoreboard.getTeam("health").setPrefix("§fHealth: §7");
            scoreboard.getTeam("health").setSuffix("" + player.getHealth());
        }
    }

    public void start() {
        new BukkitRunnable() {

            @Override
            public void run() {
                updateScoreboards();
            }

        }.runTaskTimer(plugin, 0L, 5L);
    }

}

Spoiler: MapHandler.java

Code (Java):

public class MapHandler {

    public HashMap<Player, Scoreboard> playerScoreboards = new HashMap<Player, Scoreboard>();

    public boolean checkPlayerScoreboard(Player player) {
        if (playerScoreboards.containsKey(player)) {
            return true;
        }
        return false;
    }

    public void addPlayerScoreboard(Player player, Scoreboard scoreboard) {
        if (checkPlayerScoreboard(player)) {
            playerScoreboards.remove(player);
        }
        playerScoreboards.put(player, scoreboard);

    }

    public void removePlayerScoreboard(Player player) {
        if (checkPlayerScoreboard(player)) {
            playerScoreboards.remove(player);
        }
    }

    public Scoreboard getPlayerScoreboard(Player player) {
        if (!checkPlayerScoreboard(player)) {
            Bukkit.getServer().getConsoleSender()
                    .sendMessage("§cThere was an error getting " + player.getName() + "'s scoreboard!");
            return null;
        }
        return playerScoreboards.get(player);
    }
   
}

Spoiler: PlayerJoin.java

Code (Java):

public class PlayerJoain implements Listener {
   
    private final ScoreboardManager sb = new ScoreboardManager();
   
    @EventHandler
    public void playerJoin(PlayerJoinEvent event) {
        sb.createScoreboard(event.getPlayer());
    }

}

Spoiler: PlayerLeave.java

Code (Java):

public class PlayerLeave implements Listener {
   
    private final MapHandler map = new MapHandler();

    @EventHandler
    public void playerLeave(PlayerQuitEvent event) {
        map.removePlayerScoreboard(event.getPlayer());
    }
   
}

Explanation
In onEnable() we register the PlayerJoin listener to listen for when a player joins. The last line in onEnable() runs the method from the ScoreBoardManager class to start updating scoreboards every quarter of a second (5 ticks). When a player joins, a new scoreboard is created and the player along with the scoreboard is added to a hashmap for later use. When updating, we call the scoreboard from our hashmap using Bukkit#getOnlinePlayers() as the object. As we update, the teams aren't modified rather the prefixes and suffixes are to prevent flickering. When a player leaves, they are removed from the hashmap to prevent un-needed usage of the CPU as it must look through more entries in the hashmap. If you have any questions, feel free to reply below and I will do my best to provide help.

Thanks for reading, I hope this helped.
If it did, consider leaving a rating as they are much appreciated!

 

This way of creating the scoreboards was to prevent the usage of an external API. Also, you cannot change the values to just a single scoreboard but display different content without editing packets.