簡單說下,MyBatis-plus為我們提供了預設的增删改查和一些基礎使用的條件查詢等。
直接進入代碼環節,
pom.xml 的核心依賴包:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- mybatis-plus-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- druid資料源驅動 1.1.10解決springboot從1.0——2.0版本問題-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.10</version>
</dependency>
<!-- lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
application.yml:
spring:
datasource:
druid:
username: root
password: root
url: jdbc:mysql://localhost:3306/mylocal?useSSL=false&useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8&zeroDateTimeBehavior=convertToNull
# driver-class-name: com.mysql.jdbc.Driver
initialSize: 5
minIdle: 5
maxActive: 20
maxWait: 60000
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: SELECT 1 FROM DUAL
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
poolPreparedStatements: true
maxPoolPreparedStatementPerConnectionSize: 20
useGlobalDataSourceStat: true
connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
#配置端口
server:
port: 8037
接着直接到了使用mybatis-plus (其實跟普通的mybatis使用沒什麼差別,隻是少寫一些方法。)
POJO
MyInfo.java:
PS: 這裡的主鍵設定自增需要注意
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import lombok.Data;
/**
* @Author : JCccc
* @CreateTime : 2019/12/4
* @Description :
**/
@Data
public class MyInfo {
@TableId(value = "id",type = IdType.AUTO)
private Integer id;
private Integer num;
private String name;
private Integer age;
}
Mapper
MyInfoMapper.java:
PS:可以看到我隻是額外寫了一個根據條件查詢(模拟實際的業務查詢),增删查改都沒寫,因為BaseMapper都為我們提供了這些。
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.demo.elegant.pojo.MyInfo;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
/**
* @Author : JCccc
* @CreateTime : 2019/12/4
* @Description :
**/
@Mapper
public interface MyInfoMapper extends BaseMapper<MyInfo> {
@Select("SELECT * FROM my_info where id=#{id} and name=#{name}")
MyInfo getMyInfoConditional(@Param("id") Integer id,@Param("name") String name);
}
BaseMapper 預設提供的方法:

這裡為了示範簡單的使用,我就不寫service和serviceImpl了。
直接開始接口測試:
MyInfoController.java:
import com.demo.elegant.mapper.MyInfoMapper;
import com.demo.elegant.pojo.MyInfo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
/**
* @Author : JCccc
* @CreateTime : 2019/12/4
* @Description :
**/
@RestController
public class MyInfoController {
@Autowired
MyInfoMapper myInfoMapper;
@GetMapping("/testPlus")
public void testPlus() {
MyInfo myInfo1 = new MyInfo();
myInfo1.setNum(1011909);
myInfo1.setName("one");
myInfo1.setAge(11);
int effectNum1 = myInfoMapper.insert(myInfo1);
System.out.println("添加後的影響行數:"+effectNum1+"--- 1主鍵:"+myInfo1.getId());
MyInfo myInfo2=new MyInfo();
myInfo2.setNum(1011220);
myInfo2.setName("two");
myInfo2.setAge(30);
int effectNum2 = myInfoMapper.insert(myInfo2);
System.out.println("添加後的影響行數:"+effectNum2+"--- 2主鍵:"+myInfo2.getId());
List<MyInfo> myInfoList = myInfoMapper.selectList(null);
System.out.println("查詢出來的list:"+myInfoList.toString());
// int effectNumeDelete = myInfoMapper.deleteById(2);
// System.out.println("删除後影響行數:"+effectNumeDelete);
MyInfo myInfoConditional = myInfoMapper.getMyInfoConditional(2, "two");
System.out.println("根據條件查詢出來的資料:"+myInfoConditional.toString());
}
}
OK,使用postman調用接口看看效果:
看下控制台列印情況,都是正常使用: