GeneratedValue

maven添加 <dependency> <groupId>javax.persistence</groupId> <artifactId>persistence-api</artifactId> <version>1.0.2</version> </dependency> ......

@GeneratedValue注解存在的意义主要就是为一个实体生成一个唯一标识的主键 https://blog.csdn.net/sswqzx/article/details/84337921 https://blog.csdn.net/u011781521/article/details/7221 ......