JPA @Inheritance(strategy = InheritanceType.JOINED): Missing class for indicator field value

Is it possible to have a default imple开发者_运维知识库mentation when no class is provided for an indicator field value for not raising this exception?

Missing class for indicator field value 

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This is not defined in JPA, but some providers do support more complex indicators.

If using EclipseLink, you can use a ClassExtractor to define your own code to determine the Class to use for each row.

See, http://en.wikibooks.org/wiki/Java_Persistence/Inheritance#No_class_discriminator_column