public class UserService { private static UserService instance = new UserService(); private Connection conn; public static UserService getInstance() { return instance; } public List<User> findAll() throws Exception { Statement s = conn.createStatement(); ResultSet rs = s.executeQuery("SELECT * FROM users"); List<User> out = new ArrayList(); while (rs.next()) { out.add(new User(rs.getInt(1), rs.getString(2))); } return out; } }