code: public static Collection<RDFNode> getListItemsOrFail(RDFNode node) {
  
          if (!isList(node)) {
              throw new IllegalArgumentException("Resource not an rdf:List");
          }
  
          return getListItemsOrEmpty(node);
      }
docs: Tries to get the items of an rdf:List and throws an {@link IllegalArgumentException} if it is not a list