零基础搭建boot+MybatisPlus的详细教程

CREATE   TABLE `login`(

    `id`  INT (4)  primary key auto_increment,

    `login_id`  VARCHAR (50)  UNIQUE ,

    `city` VARCHAR (50)  DEFAULT   '富平' ,

    ` password `  VARCHAR (50)

)

<dependency>

     <groupId>com.baomidou</groupId>

     <artifactId>mybatis-plus-boot-starter</artifactId>

     <version> 3.1 . 2 </version>

</dependency>

<dependency>

     <groupId>mysql</groupId>

     <artifactId>mysql-connector-java</artifactId>

</dependency>

spring:

   datasource:

     url: jdbc:mysql: //localhost:3306/test0314?characterEncoding=utf-8&serverTimezone=UTC

     username: root

     password: root

     driver- class -name: com.mysql.cj.jdbc.Driver

package com.hand.demo.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;

import com.hand.demo.entity.User;

/**

  * 用户数据访问层接口

  * */

public interface UserMapper extends BaseMapper<User> {

}

@SpringBootApplication

@MapperScan ( "com.hand.demo.mapper" )

public class Demo0318Application {

     public static void main(String[] args) {

         SpringApplication.run(Demo0318Application. class , args);

     }

}

<dependency>

            <groupId>junit</groupId>

            <artifactId>junit</artifactId>

            <scope>test</scope>

        </dependency>

package com.hand.demo;

import com.hand.demo.entity.User;

import com.hand.demo.mapper.UserMapper;

import org.junit.jupiter.api.Test;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest

class Demo0318ApplicationTests {

     @Autowired

     private UserMapper userMapper;

     /**

      * 获取UserMapper实现类对象(mybatisPlus容器会使用动态代理生成该接口的实现类对象，并注入到spring容器中

      * 所以我们只需要在这定义一个成员变量，通过注解自动注入即可)

      * */

     @Test

     public void testQueryAll() {

         List<User> userList = userMapper.selectList( null );

         System.out.println(userList);

     }

}

@TableId (type = IdType.AUTO)

    private Long id;

mybatis-plus:

   global-config:

     db-config:

       table-prefix:

       id-type: auto

mybatis-plus:

   global-config:

     db-config:

       table-prefix:

       id-type: auto

   configuration:

     map-underscore-to-camel- case : false

mybatis-plus:

   global-config:

     db-config:

       table-prefix:

       id-type: auto

   configuration:

     map-underscore-to-camel- case : false

     log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

Wrapper

           AbstractWrapper   

    QueryWrapper   UpdateWrapper

package com.hand.demo.service;

import com.baomidou.mybatisplus.extension.service.IService;

import com.hand.demo.entity.User;

public interface UserService extends IService<User> {

}

package com.hand.demo.service.Impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;

import com.hand.demo.entity.User;

import com.hand.demo.mapper.UserMapper;

import com.hand.demo.service.UserService;

@Service

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

}

@Autowired

private UserService userService;

@Test

public void testService() {

     List<User> list = userService.list();

     System.out.println(list);

}

<dependency>

            <groupId>com.baomidou</groupId>

            <artifactId>mybatis-plus-generator</artifactId>

            <version> 3.5 . 2 </version>

        </dependency>

        <dependency>

            <groupId>org.freemarker</groupId>

            <artifactId>freemarker</artifactId>

        </dependency>