What is a serialVersionUID and why should I use it?

A serialVersionUID is a unique identifier for a serializable class. It is used 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 you implement the Serializable interface in your class, it is recommended to specify a serialVersionUID value. This value should be unique across all versions of your class. If you do not specify a serialVersionUID, the Java runtime will calculate one for you based on various aspects of your class, such as its name, superclass, and the interfaces it implements.

The serialVersionUID is used during the deserialization process 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 object that has a different serialVersionUID than the one provided by the sender, then deserialization will result in an InvalidClassException.

By specifying a serialVersionUID in your class, you can ensure that the sender and receiver of a serialized object are using compatible versions of your class. This can help to prevent InvalidClassException errors during deserialization.

I hope this helps! Let me know if you have any questions.