Question

I want to change the packages of multiple classes in my application.
A nice eclipse redactor good have been great but some of my classes are Serializables and I need to support cross version compatibility.

Any Idea on how it can be done?
Can it be done automatically/semi-automatically?

Answer 1

If the class structure remains the same, you can subclass a custom ObjectInputStream, call enableResolveObject(true) in its constructor and then override readClassDescriptor() with something like that:

protected ObjectStreamClass readClassDescriptor() throws IOException, ClassNotFoundException {
    ObjectStreamClass read = super.readClassDescriptor();
    if (read.getName().startsWith("com.old.package.")) {
        return ObjectStreamClass.lookup(Class.forName(read.getName().replace("com.old.package.", "org.new.package.")));
    }
    return read;
}