Spring JdbcTemplate选择单列多行

CREATE TABLE users (
    id INT PRIMARY KEY,
    name VARCHAR(100)
);

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

public class UserDao {

    private JdbcTemplate jdbcTemplate;

    public UserDao(JdbcTemplate jdbcTemplate) {
        this.jdbcTemplate = jdbcTemplate;
    }

    public List<Integer> getAllUserIds() {
        String sql = "SELECT id FROM users";
        return jdbcTemplate.queryForList(sql, Integer.class);
    }
}

public List<Integer> getAllUserIds() {
    String sql = "SELECT id FROM users";
    return jdbcTemplate.query(sql, new RowMapper<Integer>() {
        @Override
        public Integer mapRow(ResultSet rs, int rowNum) throws SQLException {
            return rs.getInt("id");
        }
    });
}