一.结构图
创建的springboot工程
数据库
二.代码
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">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.ding</groupId>
<artifactId>demomptest</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demomptest</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.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-test</artifactId>
<scope>test</scope>
</dependency>
<!--mybatis-plus-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1</version>
</dependency>
<!--mysql依赖-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!--lombok用来简化实体类-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
config
package com.ding.demomptest.config;
import com.baomidou.mybatisplus.extension.plugins.OptimisticLockerInterceptor;
import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
/**
* @Description TODO
* @Author 丁帅帅
* @Date 21/09/19 10:13
* @Version 1.0
*/
@Configuration
@MapperScan("com.ding.demomptest.mapper")
public class MpConfig {
/**
* 乐观锁插件
*/
@Bean
public OptimisticLockerInterceptor optimisticLockerInterceptor() {
return new OptimisticLockerInterceptor();
}
/**
* 分页插件
*/
@Bean
public PaginationInterceptor paginationInterceptor() {
return new PaginationInterceptor();
}
}
entity
package com.ding.demomptest.entity;
import com.baomidou.mybatisplus.annotation.*;
import lombok.Data;
import java.util.Date;
/**
* @Description TODO
* @Author 丁帅帅
* @Date 21/09/18 20:54
* @Version 1.0
*/
@Data
public class User {
@TableId(type = IdType.ASSIGN_ID)
private Long id;
private String name;
private Integer age;
private String email;
@TableField(fill = FieldFill.INSERT)
private Date createTime; //create_time
@TableField(fill = FieldFill.INSERT_UPDATE)
private Date updateTime; //update_time
@Version
@TableField(fill = FieldFill.INSERT)
private Integer version;
@TableLogic
@TableField(fill = FieldFill.INSERT)
private Integer deleted;
}
handle
package com.ding.demomptest.handle;
import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
import org.apache.ibatis.reflection.MetaObject;
import org.springframework.stereotype.Component;
import java.util.Date;
/**
* @Description TODO
* @Author 丁帅帅
* @Date 21/09/19 10:12
* @Version 1.0
*/
@Component
public class MyMetaObjectHandler implements MetaObjectHandler {
//mp执行添加操作，这个方法执行
@Override
public void insertFill(MetaObject metaObject) {
this.setFieldValByName("createTime",new Date(),metaObject);
this.setFieldValByName("updateTime",new Date(),metaObject);
this.setFieldValByName("version",1,metaObject);
this.setFieldValByName("deleted",0,metaObject);
}
//mp执行修改操作，这个方法执行
@Override
public void updateFill(MetaObject metaObject) {
this.setFieldValByName("updateTime",new Date(),metaObject);
}
}
mapper
package com.ding.demomptest.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.ding.demomptest.entity.User;
import org.springframework.stereotype.Repository;
/**
* @Description TODO
* @Author 丁帅帅
* @Date 21/09/18 20:54
* @Version 1.0
*/
@Repository
public interface UserMapper extends BaseMapper<User> {
}
resources
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/mybatisplus?serverTimezone=GMT%2B8
spring.datasource.username=root
spring.datasource.password=root
#mybatis日志
mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
test
package com.ding.demomptest;
import com.ding.demomptest.entity.User;
import com.ding.demomptest.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.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@SpringBootTest
class DemomptestApplicationTests {
@Autowired
private UserMapper userMapper;
//修改
@Test
public void testUpdate(){
User user = new User();
user.setId(1L);
user.setName("Jeff");
int count = userMapper.updateById(user);
System.out.println(count);
}
//多个id批量查询
@Test
public void testSelect1() {
List<User> users = userMapper.selectBatchIds(Arrays.asList(1, 2, 3));
System.out.println(users);
}
//简单条件查询
@Test
public void testSelect2(){
Map<String,Object> columnMap = new HashMap<>();
columnMap.put("name","Jack");
columnMap.put("age",20);
List<User> users = userMapper.selectByMap(columnMap);
System.out.println(users);
}
//添加
@Test
public void testAdd() {
User user = new User();
user.setName("李四");
user.setAge(20);
user.setEmail("1243@qq.com");
user.setDeleted(0);
int insert = userMapper.insert(user);
System.out.println(insert);
}
//测试乐观锁
@Test
public void testOptimisticLocker() {
//根据id查询
User user = userMapper.selectById(1439422114023026690L);
//修改
user.setName("王二");
userMapper.updateById(user);
}
//根据id删除
@Test
public void testDeleteId() {
int rows = userMapper.deleteById(1439421384058949634L);
System.out.println(rows);
}
}