When and why JPA entities should implement the Serializable interface?

java hibernate serialization orm jpa
Roman picture Roman · Jan 7, 2010 · Viewed 88.3k times · Source

The question is in the title. Below I just described some of my thoughts and findings.

When I had a very simple domain model (3 tables without any relations), all my entities did NOT implement the Serializable interface.

But when the domain model became more complex, I got a RuntimeException, saying that one of my entities didn't implement Serializable.

I use Hibernate as a JPA implementation, and I wonder:

  1. Is it a vendor-specific requirement/behavior?
  2. What happens with my serializable entities? Should they be serializable for storing or for transferring?
  3. At which moment it becomes necessary to make my entity serializable?

Answer

Conor picture Conor · Jan 7, 2010

According to JPA Spec:

If an entity instance is to be passed by value as a detached object (e.g., through a remote interface), the entity class must implement the Serializable interface.

"JSR 220: Enterprise JavaBeansTM,Version 3.0 Java Persistence API Version 3.0, Final Release May 2, 2006"

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