java - JPA relations and polymorphism -

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i have following class structure (details omitted clarity):

for example:

@entity class a{  @onetomany private list<b> b;  @onetoone private c c;   }  interface b {  }  @entity @inheritance abstract class babstract implements b {  }  @entity @primarykeyjoincolumn class b1impl extends babstract  {  }  @entity @primarykeyjoincolumn class b2impl extends babstract {  }

i want load b's belonging c. class relates b c. b , c unaware of each others existence , keep way. don't know actual implementing type of b , don't care because use abstract data type b (the interface). implementation can vary on time, example, new implementation of b can added in future in new release.

is possible jpa , how do that? can't use targetentity attribute, if i'm correct, because don't know implementing class , don't care. b polymorph.

jpa doesnt work interfaces. need make b @ least abstract class entity annotation. can make b totally empty abstract class (except id field, need that) , add inheritance. reason in order entity have reference entity, there must way reference entity in database - , if there no table b there no way that.


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