mybatis执行错误但sql执行正常问题

public class SqlSessionUtil {

    public static SqlSession getSqlSession(){
        SqlSession sqlSession = null;
        try {
            // 获取核心配置文件的输入流
            InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
            // 获取SqlSessionFactoryBuilder
            SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
            // 获取SqlSessionFactory
            SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(is);
            // 获取SqlSession对象
            sqlSession = sqlSessionFactory.openSession(true);

        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return sqlSession;
    }
}

<mapper namespace="com.jingchao.mybatis.mapper.UserMapper">
    <select id="selectUserById" resultType="User">
        select * from t_user where id = #{id}
    </select>
</mapper>

public interface UserMapper{
    User selectUserById(@Param("id") Integer id);
}

SqlSession sqlSession = SqlSessionUtil.getSqlSession();
User user = sqlSession.selectOne("com.jingchao.mybatis.mapper.UserMapper.selectUserById", 1);

SqlSession sqlSession = SqlSessionUtil.getSqlSession();
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
User user = mapper.selectUserById(1);