code: private void addToCreateElements(String elementName) {
          HashMap<String, String> elementAttributes = new HashMap<>();
  
          elementAttributes.put(XsdAbstractElement.NAME_TAG, elementName);
  
          if (!createdElements.containsKey(getCleanName(elementName))){
              createdElements.put(getCleanName(elementName), new XsdElement(null, elementAttributes));
          }
      }
docs: Creates a class based on a {@link XsdElement} if it wasn't been already.
  @param elementName The name of the element.