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Re: Modifying classes



Hi,

> This is undoubtedly a very basic question but I can't find the answer so
> please just tell me where to RTFM.
> 
> I put together a set of classes to store in Ozone as a test.  This worked
> great so I decided to modify the classes to do more (and re-generated the
> proxies). But this causes the server to throw an exception
> java.io.InvalidClassException "class not compatible".
> 
> I think I deleted all the old objects and restarted the server, but to no
> avail.
> 
> Deleting the data directory and re-running ozoneInst solved the problem, but
> seems a little too violent for general use.
> 
> What is the correct way to do this?

It is very important to define a static member for each db class that looks
like that:

	public final static long serialVersionUID = 1;

This version id is used by the Java serialization to determine if a stored
object is compatible with the current class description. For more information
about it you should read the Java Manual - section 'serialization'.

Best Regards,
Gerd

-- 
________________________________________________________________
Gerd Mueller                               gerd@softwarebuero.de
softwarebuero m&b                    http://www.softwarebuero.de