code: private AbsFilter parseItemType() {
  
          AbsFilter filter;
          if (isKindTest()) {
              filter = parseKindTest();
          } else if (is("item", true)) {
              consume(TokenType.OPEN_BR, true);
              consume(TokenType.CLOSE_BR, true);
  
              filter = new ItemFilter(getTransaction());
          } else {
              final String atomic = parseAtomicType();
              filter = new TypeFilter(getTransaction(), atomic);
          }
          return filter;
      }
docs: Parses the the rule ItemType according to the following production rule:
  <p>
  [51] ItemType ::= AtomicType | KindTest | <"item" "(" ")"> .
  </p>
  
  @return filter