Use JAXB XMLAnyElement type of style to return dynamic element names

Question

I have read a lot of answers in these forums, as well as other blog posts, but I can\'t quite seem to connect the pieces together.

So, we start with a basic POJO con

Answer 1

I wasn't so far from the answer - after a bit more of experimenting I found the right combo.

Create a wrapper class for the un-mapable return type. Wrapper should contain/return List Annotate wrapper return type with @XmlAnyElement.

public class MapWrapper {
   @XmlAnyElement
    public List> properties = new ArrayList>();
}

Create an XmlAdapter that marshals to the MapWrapper

public class MapAdapter extends XmlAdapter> {
    @Override
    public MapWrapper marshal(Map m) throws Exception {
    MapWrapper wrapper = new MapWrapper();
    List> elements = new ArrayList>();
       for (Map.Entry property: m.entrySet()) {
          elements.add(new JAXBElement(
                    new QName(getCleanLabel(property.getKey())), 
          String.class, property.getValue()));
       }
       wrapper.elements=elements;
    return wrapper;
}

@Override
public Map unmarshal(MapWrapper v) throws Exception {
            // TODO
    throw new OperationNotSupportedException();
}

// Return a lower-camel XML-safe attribute
private String getCleanLabel(String attributeLabel) {
    attributeLabel = attributeLabel.replaceAll("[()]", "")
            .replaceAll("[^\\w\\s]", "_").replaceAll(" ", "_")
            .toUpperCase();
    attributeLabel = CaseFormat.UPPER_UNDERSCORE.to(CaseFormat.LOWER_CAMEL,
            attributeLabel);
    return attributeLabel;
}
}

Annotate your unmappable type with the XmlAdapter

@XmlRootElement
public class SomeBean {

    @XmlJavaTypeAdapter(MapAdapter.class)
    public LinkedHashMap getProperties() {
        return properties;
    }
}

A map like:

My Property 1    My Value 1 
My Property 2    My Value 2

Should come out as:

   
     My Value 1
     My Value 1
   

Hope this helps someone else!