springboot 整合 mybatis

Spring Boot整合MyBatis步骤如下：

1. 添加依赖

在pom.xml文件中添加以下依赖：

<!-- Spring Boot MyBatis Starter -->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.2.0</version>
</dependency>

<!-- MySQL Connector/J -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.23</version>
</dependency>

2. 配置数据源

在application.properties文件中配置数据源：

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true
spring.datasource.username=root
spring.datasource.password=root

3. 配置MyBatis

在application.properties文件中配置MyBatis：

mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.example.demo.entity

4. 编写Mapper

编写Mapper接口和Mapper映射文件。例如，创建UserMapper接口和UserMapper.xml文件。

UserMapper.java：

package com.example.demo.mapper;

import com.example.demo.entity.User;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

@Mapper
public interface UserMapper {

    List<User> findAll();

    User findById(Long id);

    void save(User user);

    void update(User user);

    void delete(Long id);
}

UserMapper.xml：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.example.demo.mapper.UserMapper">

    <resultMap id="UserResultMap" type="com.example.demo.entity.User">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="age" column="age"/>
    </resultMap>

    <select id="findAll" resultMap="UserResultMap">
        SELECT * FROM user
    </select>

    <select id="findById" resultMap="UserResultMap">
        SELECT * FROM user WHERE id=#{id}
    </select>

    <insert id="save">
        INSERT INTO user(name, age) VALUES(#{name}, #{age})
    </insert>

    <update id="update">
        UPDATE user SET name=#{name}, age=#{age} WHERE id=#{id}
    </update>

    <delete id="delete">
        DELETE FROM user WHERE id=#{id}
    </delete>

</mapper>

5. 编写Service和Controller

编写UserService和UserController类，并注入UserMapper。

UserService.java：

package com.example.demo.service;

import com.example.demo.entity.User;
import com.example.demo.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.List;

@Service
@Transactional
public class UserService {

    @Autowired
    private UserMapper userMapper;

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

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

    public void save(User user) {
        userMapper.save(user);
    }

    public void update(User user) {
        userMapper.update(user);
    }

    public void delete(Long id) {
        userMapper.delete(id);
    }
}

UserController.java：

package com.example.demo.controller;

import com.example.demo.entity.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/users")
public class UserController {

    @Autowired
    private UserService userService;

    @GetMapping("")
    public List<User> findAll() {
        return userService.findAll();
    }

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

    @PostMapping("")
    public void save(@RequestBody User user) {
        userService.save(user);
    }

    @PutMapping("")
    public void update(@RequestBody User user) {
        userService.update(user);
    }

    @DeleteMapping("/{id}")
    public void delete(@PathVariable Long id) {
        userService.delete(id);
    }
}

6. 运行测试

启动应用程序并访问http://localhost:8080/users，如果一切正常，则应该能够看到所有用户的列表。

以上是Spring Boot整合MyBatis的步骤，希望能帮助到你。