code: public boolean restoreLastMapFromArchive() {
  		boolean success = false;
  		List<Map<Object, Object>> object = null;
  		if (oldBlockHierarchy.size() > 0) {
  			object = oldBlockHierarchy.remove(oldBlockHierarchy.size() - 1);
  			if (object != null) {
  				working = object;
  				success = true;
  			}
  		}
  		return success;
  	}
docs: restore the last block hierarchy variable map from archive to working.
  
  @return true if restored successfully else false