<select id="getUserById" resultType="com.cunyu.pojo.User">
select * from user where id=#{id}
</select>
<select id="getUserByName" resultType="com.cunyu.pojo.User">
select * from user where name=#{name}
</select>
<select id="getUserByPassword" resultType="com.cunyu.pojo.User">
select * from user where password=#{password}
</select>
在测试类中测试即可;
@Test
public void testGetUserById() {
// 执行 SQL 语句
UserDao mapper = sqlSession.getMapper(UserDao.class);
User user = mapper.getUserById(2);
System.out.println(user);
// 关闭 SqlSession
sqlSession.close();
}
@Test
public void testGetUserByName() {
UserDao mapper = sqlSession.getMapper(UserDao.class);
User user = mapper.getUserByName("村雨遥");
System.out.println(user);
sqlSession.close();
}
@Test
public void testGetUserByPassword(){
UserDao mapper = sqlSession.getMapper(UserDao.class);
User user=mapper.getUserByPassword("123456");
System.out.println(user);
sqlSession.close();
}
@Test
public void testAddUser() {
UserDao mapper = sqlSession.getMapper(UserDao.class);
User user = new User(5, "小雨", "6543210");
int i = mapper.addUser(user);
System.out.println(i);
// 提交事务到数据库
sqlSession.commit();
System.out.println("添加用户成功");
sqlSession.close();
}
3. 修改操作 update
在 UserDao 添加对应接口;
/**
* @description 根据 id 修改用户
* @param user 待修改的用户对象
* @return
* @date 2020/7/14 16:04
* @author cunyu1943
* @version 1.0
*/
int updateUser(User user);
在 UserMapper.xml 中添加 update 语句;
<update id="updateUser" parameterType="com.cunyu.pojo.User">
update user set name=#{name},password=#{password} where id=#{id}
</update>
测试类中测试;
@Test
public void testUpdateUser(){
// 获取 SqlSession 对象
SqlSession sqlSession = MybatisUtils.getSqlSession();
UserDao mapper = sqlSession.getMapper(UserDao.class);
User user = mapper.getUserById(1);
user.setPassword("7891011");
int i = mapper.updateUser(user);
sqlSession.commit();
System.out.println("更新数据成功");
sqlSession.close();
}