springboot整合mybatis实现增删改查

1.新建springboot项目，连接数据库

2.导入依赖

    
        
            org.springframework.boot
            spring-boot-starter
        

        
        
            org.springframework.boot
            spring-boot-starter-web
            2.5.6
        
        
        
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.1.4
        
        
        
            mysql
            mysql-connector-java
        
        
        
            org.projectlombok
            lombok
        
        
            org.springframework.boot
            spring-boot-starter-test
            test

3.配置文件

（1）application.yml

#激活开发配置文件
spring:
  profiles:
    active: dev

（2）application-dev.yml

#端口号8888
server:
  port: 8888

#连接数据库
spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver

#绑定mapper包下的xml文件
mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.kuang.pojo

4.新建User类

package com.kuang.pojo;

import lombok.Data;

@Data
public class User {
    private Integer id;
    private String name;
    private String password;
}

5.在mapper包中新建UserMapper接口

package com.kuang.mapper;

import com.kuang.pojo.User;
import org.springframework.stereotype.Repository;

@Repository
public interface UserMapper {
    //根据id查询用户信息
    User getUserInfo(int id);
    //插入用户
    int insert (User user);
    //更新用户
    int update (User user);
    //根据id删除用户
    int deleteById(int id);
}

6.在service包中新建实现类UserService.java

package com.kuang.service;

import com.kuang.mapper.UserMapper;
import com.kuang.pojo.User;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

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

    public User getUserInfo(int id) {
        return userMapper.getUserInfo(id);
    }

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

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

    public int deleteById(int id) {
        return userMapper.deleteById(id);
    }
}

7.在controller包中新建访问类UserController.java

package com.kuang.controller;

import com.kuang.pojo.User;
import com.kuang.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class UserController {

    @Autowired
    private UserService userService;

    //通过用户id获取用户所有信息
    @RequestMapping(value = "getUser/{id}", method = RequestMethod.GET)
    public String GetUser(@PathVariable int id) {
        return userService.getUserInfo(id).toString();
    }

    //通过用户id删除用户
    @RequestMapping(value = "/delete", method = RequestMethod.GET)
    public String delete(int id) {
        int result = userService.deleteById(id);
        if (result >= 1) {
            return "删除成功";
        } else {
            return "删除失败";
        }
    }
    //根据用户id更新用户信息
    @RequestMapping(value = "/update", method = RequestMethod.POST)
    public String update(User user) {
        int result = userService.update(user);
        if (result >= 1) {
            return "修改成功";
        } else {
            return "修改失败";
        }
    }
    //插入新用户
    @RequestMapping(value = "/insert", method = RequestMethod.POST)
    public User insert(User user) {
        return userService.insert(user);
    }

}

8.在src/main/resources/mapper文件夹下新建UserMapper的映射文件UserMapper.xml