JAXB: How should I marshal complex nested data structures?

Question

I have several complex data structures like

Map< A, Set< B > >
Set< Map< A, B > >
Set< Map< A, Set< B > > >
Map<         


        

Answer 1

It looks like you're on the right track with XMLAdapter... the error message may be a clue:

class java.util.Collections$UnmodifiableMap nor any of its super class is known to this context.

are you wrapping a map using Collections.unmodifiableMap() anywhere? Where exactly does the error occur?

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(previous answer left as a stale record for the curious)

You can create custom marshaller/unmarshaller logic that works a little more straighforward than the Adapters idea (I think; I haven't used that one before).

Basically the idea is that you specify a static function to do the work, and you can also create a custom class. (I usually put the static function in the class in question, but you don't have to.) Then you put a line in your .XJB file to tell JAXB to use your static function.

Now that I took a look at my existing code, I see that all I was doing was converting an attribute string to a custom Java object. Here's the code, for reference, but it's just for attributes.

JAXB file:

(parseMethod and printMethod convert to/from attribute strings)