springboot整合mybatis plus

Spring Boot整合Mybatis Plus可以通过以下步骤实现：

1. 引入Mybatis Plus和Mybatis的依赖

在pom.xml文件中添加以下依赖：

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.4.2</version>
</dependency>
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.2.</version>
</dependency>

2. 配置数据源

在application.properties文件中配置数据源信息，例如：

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

3. 配置Mybatis Plus

在application.properties文件中添加以下配置：

# Mybatis Plus配置
mybatis-plus.mapper-locations=classpath*:mapper/**/*.xml
mybatis-plus.type-aliases-package=com.example.demo.entity

4. 编写实体类和Mapper接口

在com.example.demo.entity包下编写实体类，例如：

@Data
public class User {
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

在com.example.demo.mapper包下编写Mapper接口，例如：

public interface UserMapper extends BaseMapper<User> {
}

5. 编写Mapper XML文件

在resources/mapper目录下编写Mapper XML文件，例如：

<?xml version="1." encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.UserMapper">
    <resultMap id="BaseResultMap" type="com.example.demo.entity.User">
        <id column="id" property="id"/>
        <result column="name" property="name"/>
        <result column="age" property="age"/>
        <result column="email" property="email"/>
    </resultMap>
    <select id="selectById" resultMap="BaseResultMap">
        select * from user where id=#{id}
    </select>
    <insert id="insert" parameterType="com.example.demo.entity.User">
        insert into user(name, age, email) values(#{name}, #{age}, #{email})
    </insert>
    <update id="updateById" parameterType="com.example.demo.entity.User">
        update user set name=#{name}, age=#{age}, email=#{email} where id=#{id}
    </update>
    <delete id="deleteById" parameterType="java.lang.Long">
        delete from user where id=#{id}
    </delete>
</mapper>

6. 编写Service和Controller

在com.example.demo.service包下编写Service接口和实现类，例如：

public interface UserService extends IService<User> {
}

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
}

在com.example.demo.controller包下编写Controller类，例如：

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService userService;

    @GetMapping("/{id}")
    public User getById(@PathVariable Long id) {
        return userService.getById(id);
    }

    @PostMapping
    public boolean save(@RequestBody User user) {
        return userService.save(user);
    }

    @PutMapping
    public boolean updateById(@RequestBody User user) {
        return userService.updateById(user);
    }

    @DeleteMapping("/{id}")
    public boolean removeById(@PathVariable Long id) {
        return userService.removeById(id);
    }
}

7. 启动应用程序

运行Spring Boot应用程序，访问http://localhost:808/user/{id}可以查询用户信息，访问http://localhost:808/user可以新增用户信息，访问http://localhost:808/user可以更新用户信息，访问http://localhost:808/user/{id}可以删除用户信息。