Add tests for inherited entity reference equality

[ivan-zaitsev]

Hi, Vlad. I wrote some tests for equality when we have inheritance.

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Test class - InheritedEntityReferenceEqualityTest

Test method - testInheritedEntityReferenceEqualityInOnTransaction

When we try to persist entity in one transaction and after it use getReference everything works as expected.

Test method - testInheritedEntityReferenceEqualityInDifferentTransactions

In this test case we separate entity persist from getReference, and after it the instanceof or o.getClass() check for inherited entity does`t work.

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Example: postProxy.hashCode() == post.hashCode(); // = true postProxy.getClass() == post.getClass(); // = false postProxy instanceof Post // = false post instanceof Post // = true postProxy.equals(post); // = true post.equals(postProxy); // = false

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Possible solutions to resolve this problem: use Hibernate.getClass(o) instead of !(o instanceof Topic) or getClass() != o.getClass() in equals method.

[vladmihalcea]

Cool. I'll have to investigate it when I have some time. Currently, I'm very busy launching a new product.