有没有办法用 JPA 存储“扩展枚举”

Question

Is there a way to store "extended enum" with JPA?
I'm working with abstract object in my spring boot project and my base object can have multiple states. The object extending it can have the base state but also other specific states. You can't extend enum in Java, so my I first tought of using an interface with a default method isCommon to discriminate between my common enum values and my extended enum values in my services.
However I can't use the annotation @Enumerated on my property anymore. Is there a way to make it work or another pattern I could use?
A small code sample to provide some context:

@Entity
abstract class AbstractFoo {
   public StateInterface state;
}

@Entity
class ConcreteFoo extends AbstractFoo {

}

@Service
class ConcreteFooService {
    public boolean isCommonState(ConcreteFoo foo) {
        return foo.state.isCommon();
    }
}

interface StateInterface {
   default boolean isCommon() {
       return false;
   }
}

enum CommonState extends StateInterface {
   BEGIN, END;
   
   @Override
   boolean isCommon() {
      return true;
   }
}

enum SpecificState extends StateInterface {
    MIDDLE;
}

Answer 1

I would suggest you using the following Enum instead:

enum State {
    BEGIN(true), MIDDLE(false), END(true);

    private final boolean common;

    State(boolean common) {
        this.common = common;
    }

    public boolean isCommon() {
       return common;
    }
}

For your use case, this is the best I can think of.