code: public List getErrors() {
  		if (hasChilds()) {
  			List ret = new ArrayList(0);
  			Iterator it = getChilds().iterator();
  			while (it.hasNext()) {
  				ret.addAll(((AbcNode) it.next()).getErrors());
  			}
  			return ret;
  		} else {
  			return errors != null ? errors : new ArrayList(0);
  		}
  	}
docs: Returns a List of errors in all childs, grand-childs...