import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;

import java.sql.*;


public class Main extends JavaPlugin {

    String host, port, database, username, password;
    static Connection c;

    @Override
    public void onEnable() {
        this.getCommand("stats").setExecutor(new Stats());
        host = "localhost";
        port = "3306";
        database = "TestDatabase";
        username = "user";
        password = "pass";
        try {
            openConnection();
            Statement statement = c.createStatement();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onDisable() {
    }

    public void openConnection() throws SQLException, ClassNotFoundException {
        if (c != null && !c.isClosed()) {
            return;
        }
        Class.forName("com.mysql.jdbc.Driver");
        c = DriverManager.getConnection("jdbc:mysql://"
                        + this.host + ":" + this.port + "/" + this.database,
                this.username, this.password);
    }

    //statement.executeUpdate("INSERT INTO SStats (PLAYERNAME, BALANCE) VALUES ('Playername', 100);");

    public class Stats implements CommandExecutor {

        //This method is called, when somebody uses our command
        @Override
        public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
            if (sender instanceof Player) {
                ResultSet result = statement.executeUpdate("INSERT INTO...blablabla");
            }
        }

            // If the player (or console) uses our command correct, we can return true
            return true;
        }

}