黑马springboot中整合mybatis中的删除

1. 首先，在pom.xml文件中添加mybatis和mysql依赖：

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.2.0</version>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

2. 在application.properties文件中配置数据库信息：

spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

mybatis.mapper-locations=classpath:mapper/*.xml

3. 创建一个测试实体类：

public class User {
    private Long id;
    private String username;
    private String password;
    // 省略getter和setter方法
}

4. 创建一个UserMapper接口：

@Mapper
public interface UserMapper {
    int insert(User user);
    int update(User user);
    int delete(Long id);
    User selectById(Long id);
    List<User> selectAll();
}

5. 创建一个UserMapper.xml文件，定义相关SQL语句：

<mapper namespace="com.example.demo.mapper.UserMapper">
    <resultMap id="BaseResultMap" type="com.example.demo.entity.User">
        <id column="id" property="id" />
        <result column="username" property="username" />
        <result column="password" property="password" />
    </resultMap>

    <select id="selectById" resultMap="BaseResultMap">
        select * from user where id = #{id}
    </select>

    <select id="selectAll" resultMap="BaseResultMap">
        select * from user
    </select>

    <insert id="insert" parameterType="com.example.demo.entity.User">
        insert into user (username, password)
        values (#{username}, #{password})
    </insert>

    <update id="update" parameterType="com.example.demo.entity.User">
        update user
        set username = #{username},
            password = #{password}
        where id = #{id}
    </update>

    <delete id="delete" parameterType="java.lang.Long">
        delete from user
        where id = #{id}
    </delete>
</mapper>

6. 在UserService中注入UserMapper：

@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;

    public int insert(User user) {
        return userMapper.insert(user);
    }

    public int update(User user) {
        return userMapper.update(user);
    }

    public int delete(Long id) {
        return userMapper.delete(id);
    }

    public User selectById(Long id) {
        return userMapper.selectById(id);
    }

    public List<User> selectAll() {
        return userMapper.selectAll();
    }
}

7. 在Controller中调用UserService中的delete方法：

@RestController
public class UserController {
    @Autowired
    private UserService userService;

    @DeleteMapping("/users/{id}")
    public String deleteUser(@PathVariable("id") Long id) {
        int result = userService.delete(id);
        if (result > 0) {
            return "删除成功";
        } else {
            return "删除失败";
        }
    }
}

这样就完成了使用mybatis在springboot中整合mysql的删除操作。