What does it mean: The serializable class does not declare a static final serialversionUID field
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  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/2288937/what-does-it-mean-the-serializable-class-does-not-declare-a-static-final-serial">What does it mean: The serializable class does not declare a static final serialVersionUID field?</a>  </p>
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<p>I know this warning will go away if I just follow the instruction to create the field but I wonder about the background, why and when was this added, what is the advantage of doing it this way now?</p>

<p><code>The serializable class does not declare a static final serialversionUID field...</code></p>
