本文着重讲解了Mybatis-plus实现主键自增和自动注入时间的代码实例，文中通过代码实例讲解的非常细致，对大家的工作和学习具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧
mybatis-plus依赖导入
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.2</version>
</dependency>
建议使用3.3.0后的版本。
导入mybatis-plus就不用导入mybatis了，冲突！
连接数据库
spring.datasource.username=root spring.datasource.password=19981204 spring.datasource.url=jdbc:mysql://localhost:3306/mybatis_plus?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl//配置默认日志
设置主键自增
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
@TableId(type = IdType.AUTO)
private Long id;
private String name;
private Integer age;
private String email;
}
使用注解 @TableId(type=IdType.AUTO),同时将数据库中的id字段设置为自增即可。
编写配置类来进行自动注入时间（继承元数据类并重写它的insertFill和updateFill方法）
使用注解@TableFiled(fill=FieldFill.INSERT)
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
@TableId(type = IdType.AUTO)
private Long id;
private String name;
private Integer age;
private String email;
@TableField(fill = FieldFill.INSERT)
private LocalDateTime createTime;
@TableField(fill = FieldFill.INSERT_UPDATE)
private LocalDateTime updateTime;
}
package com.ls.handler;
import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
import org.apache.ibatis.reflection.MetaObject;
import org.springframework.stereotype.Component;
import java.time.LocalDateTime;
/**
* @author dell
*/
@Component
public class MyMetaObjectHandler implements MetaObjectHandler {
@Override
public void insertFill(MetaObject metaObject) {
this.strictInsertFill(metaObject,"createTime", LocalDateTime.class,LocalDateTime.now());
this.strictUpdateFill(metaObject,"updateTime",LocalDateTime.class,LocalDateTime.now());
}
@Override
public void updateFill(MetaObject metaObject) {
this.strictUpdateFill(metaObject,"updateTime",LocalDateTime.class,LocalDateTime.now());
}
}
