Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/tournament_system?"
            + "user=root&password=root");

    java.sql.PreparedStatement ps = conn
            .prepareStatement("  insert into PLAYER (ID, NAME, SURNAME, CLUB,  WORLD_RANKING, USER_ID)  VALUES(?, ?, ?, ?,  ?, ?)");
    ps.setInt(1, 100001);
    ps.setString(2, "ěščřž");
    ps.setString(3, "xxx");
    ps.setString(4, null);
    ps.setInt(5, 5);
    ps.setInt(6, 1);
    ps.executeUpdate();

INSERT INTO `tournament_system`.`PLAYER` (`ID`, `NAME`, `SURNAME`, `CLUB`, `PLAYER_DISCRIMINATOR`, `WORLD_RANKING`, `USER_ID`) VALUES ('10002', 'ěščřž', 'qqq', NULL, 'qqq', NULL, '1');

Server: Localhost via UNIX socket
Server version: 5.5.34-0ubuntu0.12.10.1
Protocol version: 10
User: root@localhost
MySQL charset: UTF-8 Unicode (utf8)

Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/tournament_system?"
        + "user=root&password=root&characterEncoding=UTF-8");