public CollectionChildDescriptionImpl getCollectionChildDescription(String tagName) {
   checkInitialized();
   return myCollections.findDescription(tagName);
 }
 public AttributeChildDescriptionImpl getAttributeChildDescription(String attributeName) {
   checkInitialized();
   return myAttributes.findDescription(attributeName);
 }
 public FixedChildDescriptionImpl getFixedChildDescription(String tagName) {
   checkInitialized();
   return myFixeds.findDescription(tagName);
 }