JDBC program is stuck after closing

public class JdbcTest {
  public static void main(String [] args) throws ClassNotFoundException, SQLException {
    Class.forName("org.apache.tajo.jdbc.TajoDriver");

    Connection conn = DriverManager.getConnection("jdbc:tajo://127.0.0.1:26002/tpch");

    Statement stmt = null;
    ResultSet rs = null;
    try {
      stmt = conn.createStatement();
      rs = stmt.executeQuery("select count(*) from customer");
      System.out.println(rs.next());
      System.out.println(rs.getInt(1));

    } catch (SQLException e) {
      System.err.println(e.getMessage());
    } finally {
      System.out.println("close start");
      if (rs != null) rs.close();
      System.out.println("rs close end");
      if (stmt != null) stmt.close();
      System.out.println("stmt close end");
      if (conn != null) conn.close();
      System.out.println("conn close end");
    }
  }
}