如何快速掌握mybatis基础入门技巧？

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配置和使用MyBatis查询用户信息：

sql配置MyBatis连接和Mapper：

1.在mybatis-config.xml中配置数据库连接信息。

2.创建UserMapper接口，定义selectUserById方法。

xml

javapublic interface UserMapper { User selectUserById(Integer id);}

2. 创建UserMapper.xml文件，编写selectUserById SQL语句。

xml SELECT * FROM userinfo WHERE id=#{id}

3. 在服务层调用Mapper接口的方法，获取用户信息。

javapublic class UserService { private final SqlSessionFactory sqlSessionFactory;

public UserService(SqlSessionFactory sqlSessionFactory) { this.sqlSessionFactory=sqlSessionFactory; }

public User getUserById(Integer id) { try (SqlSession session=sqlSessionFactory.openSession()) { UserMapper mapper=session.getMapper(UserMapper.class); return mapper.selectUserById(id); } }}

4. 在控制器层调用服务层的方法，返回用户信息。

java@RestController@RequestMapping(/users)public class UserController { private final UserService userService;

public UserController(UserService userService) { this.userService=userService; }

@GetMapping(/{id}) public ResponseEntity getUserById(@PathVariable Integer id) { User user=userService.getUserById(id); return ResponseEntity.ok(user); }}

这样，你就可以通过访问http://localhost:8080/users/{id}来获取指定ID的用户信息了。

配置和使用mybatis

select * from userinfo select * from userinfo where id=#{id} delete userinfo where id=#{id} package org.jxnd.test; import java.io.IOException; import java.io.InputStream; import java.util.List; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import org.jxnd.bean.UserInfo; public class Test { public static void main(String[] args) throws Exception { String resource = "mybatis.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); SqlSession session =sqlSessionFactory.openSession(); // session.delete("user.deleteById", 15); System.out.println(session.selectOne("user.getUserById",15)); // List list=session.selectList("user.getAllUsers"); // for (UserInfo userInfo : list) { // System.out.println(userInfo); // } session.commit(); session.close(); } }