code: static boolean scanForChildTag(XMLStreamReader reader, String tagName)
  			throws XMLStreamException {
  		assert reader.isStartElement();
  
  		int level = -1;
  		while (reader.hasNext()) {
  			//keep track of level so we only search children, not descendants
  			if (reader.isStartElement()) {
  				level++;
  			} else if (reader.isEndElement()) {
  				level--;
  			}
  			if (level < 0) {
  				//end parent tag - no more children
  				break;
  			}
  
  			reader.next();
  
  			if (level == 0 && reader.isStartElement() && reader.getLocalName().equals(tagName)) {
  				return true; //found
  			}
  		}
  		return false; //got to end of parent element and not found
  	}
docs: Scan xml for tag child of the current element
  
  @param reader reader, must be at "start element" @nonnull
  @param tagName name of child tag to find @nonnull
  @return if found tag
  @throws XMLStreamException on error