What is the purpose of using serialVersionUID here?
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Why should I bother about serialVersionUID?
I was examining the Struts2 validation documentation. Even here it is defined:
private static final long serialVersionUID = -7505437345373234225L;
What is the purpose of using serialVersionUID, how to use it(with random numbers?) and what is the purpose of using it at that documentation?
The serialVersionUID is an identifier for serialized objects. If the serialVersionUID of a serialized object doesn't match to the current serialVersionUID of that class, then the deserialization throws an InvalidClassException . The UID is intended to be changed on every structural change of a class.