public static PsiReference[] getReferencesForAttributeValue(@Nullable XmlAttributeValue element,
                                                              PairFunction<? super String, ? super Integer, ? extends PsiReference> refFun) {
    if (element == null) {
      return PsiReference.EMPTY_ARRAY;
    }
    String text = element.getText();
    String urls = StringUtil.unquoteString(text);
    StringTokenizer tokenizer = new StringTokenizer(urls);
    List<PsiReference> result = new ArrayList<>();
    while (tokenizer.hasMoreTokens()) {
      String token = tokenizer.nextToken();
      int index = text.indexOf(token);
      PsiReference ref = refFun.fun(token, index);
      if (ref != null) {
        result.add(ref);
      }
    }
    return result.toArray(PsiReference.EMPTY_ARRAY);
  }
public static PsiReference[] getReferencesForAttributeValue(@Nullable XmlAttributeValue element,
                                                              PairFunction<? super String, ? super Integer, ? extends PsiReference> refFun)