JPA Resolved [java.lang.IllegalArgumentException: Id must be assignable to Serializable: null] 问题： JPA Entity 如下 @Table (name= "EMP") @Inheritance @DiscriminatorColumn (name="EMP TPE") public abstract class Employee {...} @Entity @DiscriminatorValue ("CEmp") public class contractemployee extenas Employee{...} @MappedSuperclass public abstract class CompanyEmployee extends Employee {...} @Entity @DiscriminatorValue ("FTEmp") public class FullTimeEmployee extenas companyemployee {....} @Entity (name= "PTEmp") public class PartTimeEmployee extends CompanyEmployee {....} 123456789101112131415161718 @Table (name= "EMP") @Inheritance@DiscriminatorColumn (name="EMP TPE") public abstract class Employee {...} @Entity@DiscriminatorValue ("CEmp")public class contractemployee extenas Employee{...} @MappedSuperclasspublic abstract class CompanyEmployee extends Employee {...} @Entity@DiscriminatorValue ("FTEmp")public class FullTimeEmployee extenas companyemployee {....} @Entity (name= "PTEmp")public class PartTimeEmployee extends CompanyEmployee {....} &nbs… Read More
SpringBoot Caused by: com.mysql.cj.exceptions.ConnectionIsClosedException: No operations allowed after connection closed. 问题： spring boot + hikari + mysql [crayon-673ed6114dcbc6… Read More
【未解决】aliyun oss 通过 x-oss-ac-source-ip 限制 ip 下载文件 问题： aliyun oss 限制下载，一种是设置 bucket 访问策略限制ip，还可以通过 x-oss-a… Read More