code: @Nonnull
      public static NodeID getNodeID(String id) {
          String nonBlankId = id == null || id.isEmpty() ? nextAnonymousIRI() : id;
          return new NodeID(nonBlankId);
      }
docs: Gets a NodeID with a specific identifier string
  
  @param id
  The String that identifies the node. If the String doesn't start
  with "_:" then this will be concatenated to the front of the
  specified id String; if the string is empty or null, an
  autogenerated id will be used.
  @return A NodeID