All nodes loadable by the DasNodeFactory should inherit from this package private abstract class. It supports the general 3-phase construction. In general the construction phases are: 1. Create a stub object that knows what kind of thing it is and who it's parents are. 2. Resolve one of the URLs to get a full definition of the object. 3. Possibly merge information from a secondary URL if requested.
Get the root node list as a string with some separator and prefix