java - JPA Inheritence IdClass -


How to use IDclass in multiple heritage units overall key case? 

  @IdClass (IdClassEntity1 classifieds) class Entity1 {Private long e1pk1; Private long e1pk2; } @ ID Class (ID Classy Class 2.) Class Entity2 Entity1 {Private long e2pk1; Private long E2P2; } Class Entity3 Entity2 {Private long e3pk1; Private long E3 PK2; }

What should be IdClassEntity2: 

  Class IdClassEntity2 {Private long e1pk1; Private long e1pk2; Private long E2 PK1; Private long E2P2; }

or 

  Class IdClassEntity2 {Private IdClassEntity1 idClassEntity1; Private long E2 PK1; Private long E2P2; }

You can use @MappedSuperClass or as @EdClass . For example, by using @MappedSuperClass , you can: 

  @MappedSuperClass @IdClass (IdClassEntity1) .class) Public Class Entity1 {@Id Private Long e1pk; @ Id private long e1pk; ... @Entity Public Class Entity2 Entity1 {...]

using @Entity extends, follow the same pattern


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