If you have access to the code base, you could use the SerialVer task for Ant to insert and to modify the serialVersionUID in the source code of a serializable class and fix the problem once for all. If you can’t, or if this is not an option (e.g. if you have already serialized some … Read more
As far as I can tell, that would be only for compatibility with previous releases. This would only be useful if you neglected to use a serialVersionUID before, and then made a change that you know should be compatible but which causes serialization to break. See the Java Serialization Spec for more details.
From the javadoc: The serialization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization. If the receiver has loaded a class for the … Read more
The docs for java.io.Serializable are probably about as good an explanation as you’ll get: The serialization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect … Read more