Give Few Examples Of Incompatible Changes In Java Serialization?

1.	Give Few Examples Of Incompatible Changes In Java Serialization?
Answer» CHANGING implementation from Serializable to Externalizable INTERFACE, Deleting an existing Serializable field, Changing non-transient field to transient, non-static to static, Changing the field type, Updating the CLASS PACKAGE. Modifying the writeObject() / readObject() method, we MUST not modify these methods, though adding or removing is a compatible change.

Answer»

CHANGING implementation from Serializable to Externalizable INTERFACE,
Deleting an existing Serializable field,
Changing non-transient field to transient, non-static to static,
Changing the field type,
Updating the CLASS PACKAGE.
Modifying the writeObject() / readObject() method, we MUST not modify these methods, though adding or removing is a compatible change.

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