Solved Save the level

What exactly do you mean by „saving the level“?

 

What... why do you.
I don't know... let level implement ConfigurationSerializable then creat a static method "deserialize" that accepts a single Map< String, Object> and returns the class?
Just dont forget to call ConfigurationSerialization.registerClass(Level.class)?

 

Oh ok.
Create a file per player that is named after his uuid. Then write a value inside using the Yaml configuration API from Spigot.
When loading just get the file 'uuid'.yml and load the value(s) again.

 

I think you have to elaborate a bit more on what you mean by "save".

 

Hi, try this... it seems to work

Code (Java):

public class Experience extends JavaPlugin implements Listener {

    public File players;

    public FileConfiguration pl;

    public void onEnable() {

        Bukkit.getPluginManager().registerEvents(this, this);

        players = new File("players.yml");

        if (!players.exists()) {

            try {

                players.createNewFile();

            } catch (Exception e) {

                System.out.println("[Experience] An error as occured while creating the players.yml file.");

            }

        }

        YamlConfiguration.loadConfiguration(players);

    }

    @EventHandler
    public void onJoin(PlayerJoinEvent e) {

        if (isNewPlayer(e.getPlayer())) {

            pl.set(e.getPlayer().getUniqueId().toString(), e.getPlayer().getExpToLevel());

        }

    }

    @EventHandler
    public void expModify(PlayerExpChangeEvent e) {

        pl.set(e.getPlayer().getUniqueId().toString(), e.getPlayer().getExpToLevel());

    }

    public boolean isNewPlayer(Player player) {

        try {

            pl.getString(player.getUniqueId().toString());

            return false;

        } catch (Exception e) {

            return true;

        }

    }

}