SEC-2817: ObjectIdentityImpl.equals method doesn't allow comparing ObjectIdentity instances from different classes

Kenan Sevindik (Migrated from SEC-2817) said:

Inside ObjectIdentityImpl.equals(..) method, target arg object is expected of type ObjectIdentityImpl. However, we can have another implementation of ObjectIdentity interface and an instance of it can be passed into that equals method as well.

Let's say I create a CustomObjectIdentity class of type ObjectIdentity, have a domain object of type: x.y.Foo with id: Long(1), and create two ObjectIdentity instances representing that domain object.

1. ObjectIdentity oid1 = new ObjectIdentityImpl(Foo.class,1L);
2. ObjectIdentity oid2 = new CustomObjectIdentity(Foo.class,1L);

IMO, oid1.equals(oid2) should return true here. Instead of checking if target arg object is of type ObjectIdentityImpl within equals method, it should just check if target object is of type ObjectIdentity and obtain type and identifier values via getters to evaluate the equals method.

Start at ObjectIdentityImpl.equals and inspect the ObjectIdentity interface getters used to compare the object type and identifier. Verify the behavior with an ObjectIdentityImpl and another ObjectIdentity implementation representing the same domain object; done means the two instances compare equal.