引入依赖

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<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.2</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.10</version>
</dependency>

application.yml配置

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server:
port: 8080
servlet:
context-path: /
tomcat:
uri-encoding: UTF-8

spring:
servlet:
multipart:
enabled: true
file-size-threshold: 0
max-file-size: 10MB
max-request-size: 100MB
#数据库连接配置
datasource:
type: com.alibaba.druid.pool.DruidDataSource
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/db_test?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8
username: root
password: 123456
jackson:
time-zone: GMT+8
date-format: yyyy-MM-dd HH:mm:ss
mybatis-plus:
global-config:
db-config:
id-type: auto
# 如果是放在src/main/java目录下 classpath:/com/*/*/mapper/*Mapper.xml
# 如果是放在resource目录 classpath:/mapper/**.xml
mapper-locations: classpath:/mapper/**.xml

添加注解

启动类里也需要加一个mapper扫描配置@MapperScan(“com.ledao.mapper”)

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package com.ledao;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
* @author LeDao
*/
@MapperScan("com.ledao.mapper")
@SpringBootApplication
public class MyBatisPlusDemoApplication {

public static void main(String[] args) {
SpringApplication.run(MyBatisPlusDemoApplication.class, args);
}

}

测试

表结构

img

BlogType实体类

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package com.ledao.entity;

import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

/**
* @author LeDao
* @company
* @create 2021-07-22 22:14
*/
@Data
@TableName(value = "t_blogtype")
public class BlogType {

@TableId
private Integer id;
private String name;
@TableField(value = "sortNum")
private Integer sortNum;
}

BlogTypeMapper

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package com.ledao.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.ledao.entity.BlogType;

/**
* @author LeDao
* @company
* @create 2021-07-22 22:15
*/
public interface BlogTypeMapper extends BaseMapper<BlogType> {
}

测试代码

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package com.ledao;

import com.ledao.entity.BlogType;
import com.ledao.mapper.BlogTypeMapper;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;

import javax.annotation.Resource;
import java.util.List;

@SpringBootTest
class MyBatisPlusDemoApplicationTests {

@Resource
private BlogTypeMapper blogTypeMapper;

@Test
void contextLoads() {
List<BlogType> blogTypeList = blogTypeMapper.selectList(null);
for (BlogType blogType : blogTypeList) {
System.out.println(blogType.getId() + "," + blogType.getName() + "," + blogType.getSortNum());
}
}

}

结果

img