SpringBoot使用Mybatis-puls实现增删改查_springbootmybatisplus增删改查

一、Mybatis和Mybatis-Plus

• Mybatis是一个优秀的持久性框架，它简化了 jdbc 的代码，可以使用简单的 xml 或注解来配置来映射;
• mybatis-plus 是 mybatis 的增强工具，它在 mybatis 的基础上又添加了许多的功能，在 mybatis-plus 上既可以使用自身特有的功能，还可以使用 mybatis 的原生功能；所以说mybatis-plus 是为简化开发，提高效率而生。它封装了基本的增删改查操作，使我们自己不需要再去写很多重复的代码，大大解放了生产力！

二、目录结构

三、pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
 
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.llh</groupId>
    <artifactId>spring-boot-demo</artifactId>
    <version>1.0.0</version>
    <name>spring-boot-demo</name>
    <description>springboot project description</description>
 
    <properties>
        <mybatis-spring-boot.version>2.1.4</mybatis-spring-boot.version>
        <mybatis-plus.version>3.4.2</mybatis-plus.version>
    </properties>
 
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
 
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
 
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
 
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis-spring-boot.version}</version>
        </dependency>
 
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>${mybatis-plus.version}</version>
        </dependency>
 
    </dependencies>
 
</project>
 

四、application.properties

application.properties配置文件

server:
  port: 8080
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/budongchan?serverTimezone=UTC&userUnicode=true&useSSL=false
    username: root
    password: 123456
  servlet:
    multipart:
      max-file-size: 5MB  # 限制文件大小为5MB
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher
 

五、逻辑代码

SpringBootDemoApplication 类

package com.example.budongchan;
 
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;
import springfox.documentation.swagger2.annotations.EnableSwagger2;
 
@SpringBootApplication
@MapperScan("com.example.budongchan.mapper")
public class BudongchanApplication {
 
    public static void main(String[] args) {
        SpringApplication.run(BudongchanApplication.class, args);
    }
 
}

实体类：OrderPosition 类

package com.example.budongchan.po;
 
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.experimental.Accessors;
 
import java.io.Serializable;
 
/**
 * <p>
 * 
 * </p>
 *
 * @author yixin
 * @since 2023-05-06
 */
@Data
@EqualsAndHashCode(callSuper = false)
@Accessors(chain = true)
public class OrderPosition implements Serializable {
 
    private static final long serialVersionUID = 1L;
 
    /**
     * 主键
     */
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;
 
    /**
     * 省
     */
    private String provice;
 
    /**
     * 市
     */
    private String city;
 
    /**
     * 预约中心
     */
    private String center;
 
    /**
     * 窗口数量
     */
    private Integer windows;
 
 
}

Mapper 类：OrderPositionMapper类（dao层基本的增删改查操作）

package com.example.budongchan.mapper;
 
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.budongchan.po.OrderPosition;
 
/**
 * <p>
 *  Mapper 接口
 * </p>
 *
 * @author yixin
 * @since 2023-05-06
 */
public interface OrderPositionMapper extends BaseMapper<OrderPosition> {
 
}

Service 类：OrderPositionService 类

package com.example.budongchan.service;
 
import com.baomidou.mybatisplus.extension.service.IService;
import com.example.budongchan.dto.PageDto;
import com.example.budongchan.dto.Result;
import com.example.budongchan.po.OrderPosition;
import com.example.budongchan.po.OrderServetype;
 
import javax.servlet.http.HttpServletRequest;
 
/**
 * <p>
 *  服务类
 * </p>
 *
 * @author yixin
 * @since 2023-05-06
 */
public interface OrderPositionService extends IService<OrderPosition> {
    public Result getmessage(PageDto pageDto) ;
    public Result getOneMessage(Long id);
 
 
    Result modifyCenter(OrderPosition orderPosition);
 
}

ServiceImpl 类：OrderPositionServiceImpl 类

package com.example.budongchan.service.impl;
 
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.example.budongchan.dto.PageDto;
import com.example.budongchan.dto.Result;
import com.example.budongchan.mapper.OrderPositionMapper;
import com.example.budongchan.po.OrderPosition;
import com.example.budongchan.po.OrderServetype;
import com.example.budongchan.service.OrderPositionService;
import com.example.budongchan.service.OrderServetypeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author yixin
 * @since 2023-05-06
 */
@Service
public class OrderPositionServiceImpl extends ServiceImpl<OrderPositionMapper, OrderPosition> implements OrderPositionService {
    @Autowired
    OrderServetypeService orderServetypeService;
 
    @Override
    public Result getmessage(PageDto pageDto) {
        Page<OrderPosition> page = new Page<>(pageDto.getPageNum(), pageDto.getPageSize());
        IPage<OrderPosition> pageOrder = this.page(page,null);
        System.out.println(pageOrder.getRecords());
        return Result.success("查询成功",pageOrder);
    }
 
    @Override
    public Result getOneMessage(Long id) {
        OrderPosition one = this.getOne(new LambdaQueryWrapper<OrderPosition>().eq(OrderPosition::getId, id));
        return Result.success("成功",one);
    }
 
    @Override
    public Result modifyCenter(OrderPosition orderPosition) {
        boolean update = this.update(orderPosition, new LambdaQueryWrapper<OrderPosition>().eq(OrderPosition::getId, orderPosition.getId()));
        if(update){
            return Result.success("修改成功");
        }else{
            return Result.error("修改失败");
        }
}
 
 
}

Controller 类：OrderPositionController 类

package com.example.budongchan.controller;
 
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.example.budongchan.dto.PageDto;
import com.example.budongchan.dto.Result;
import com.example.budongchan.global.R;
import com.example.budongchan.po.*;
import com.example.budongchan.service.*;
import io.swagger.annotations.Api;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
 
import javax.xml.ws.RequestWrapper;
 
@Api(tags = "管理员")
@RestController
public class managetController {
    @Autowired
    OrderPositionService orderPositionService;
   
    @Autowired
    ManagerService managerService;
    @PostMapping("/getmessage")
    public Result getmessage(@RequestBody PageDto pageDto){
        return orderPositionService.getmessage(pageDto);
    }
    @GetMapping("/getonemessage/{id}")
    public Result getOneMessage(@PathVariable Long id){
 
        return  orderPositionService.getOneMessage(id);
    }
    @PostMapping("/modifyCenter")
    public Result modifyCenter(@RequestBody OrderPosition orderPosition){
        return orderPositionService.modifyCenter(orderPosition);
    }
    
    @GetMapping("/getType/{position}")
    public Result getType(@PathVariable String position){
 
        return orderServetypeService.getType(position);
    }
   
}

• Mybatis属于半配置型的数据持久化框架，JPA是直接封装了所有的SQL操作，相对于JPA来说Mybatis更灵活，可以自定义SQL。
• Mybatis-Plus又为你封装了常用的增删改查操作，这样既可以在特殊情况下自定义SQL，又避免了写大量重复的增删改查。