Using readClassDescriptor() and maybe resolveClass() to permit Serialization versioning

Question

I am investigating different options in the Java Serialization mechanism to allow flexibility in our class structures for version-tolerant storage (and advocating for a diff

Answer 1

I haven't tinkered with class descriptors much enough, but if your problem is just about renaming and repackaging there is a much easier solution for that. You could just simply edit your serialized data file with a text editor and just replace your old names with new ones. it's there in a human-readable form. for example suppose we have this OldClass placed inside oldpackage and containing an oldField, like this:

package oldpackage;

import java.io.Serializable;

public class OldClass implements Serializable
{
    int oldField;
}

Now when we serialize an instance of this class and get something like this:

¬í sr oldpackage.OldClasstqŽÇ§Üï I oldFieldxp    

Now if we want to change class's name to NewClass and put inside newpackage and change its field's name to newField, I simply rename it the file, like this:

¬í sr newpackage.NewClasstqŽÇ§Üï I newFieldxp    

and define the appropriate serialVersionUID for the new class.

That's all. No extending and overriding required.