[maximuszen]

serializable class SERVLETNAME does not declare a static final serial/VersionUID field of type long

I get this warning. Can someone tell me what it means or how I can get rid of it.

[Scott Anderson]

It means you have a serializable class but have not declared the serialVersionUID field.
See: http://java.sun.com/j2se/1.5.0/docs/api/java/io/Serializable.html

[maximuszen]

Thank you for your reply. I read the documentation. I am a novice so what I understand is that it is an internal mechanism to maintain serial objects. So I should explicity declare

ANY-ACCESS-MODIFIER static final long serialVersionUID = 42L;

I can make ANY-ACCESS-MODIFIER public or private. I’m not sure why this doesn’t make a difference. This is going to be a simpleton question. So if you assign a static value for this object, how does the JVM maintain uniqueness of the various objects. Does it not better because it is a servlet?

The number can I assume I can assign any random value to various my servlets because this is where I can the warning.

Would very much appreciate your comments.

John

[jhm]

The easiest way for fixing the “missing-serial/VersionUID” warning is using Eclipse Quick-Fix (Ctrl-1). I suggest using the “Add generated serial version ID”.

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