private void annotateExternally(
     @NotNull PsiModifierListOwner listOwner,
     @NotNull String annotationFQName,
     @Nullable final XmlFile xmlFile,
     @NotNull PsiFile codeUsageFile,
     PsiNameValuePair[] values) {
   if (xmlFile == null) return;
   try {
     final XmlDocument document = xmlFile.getDocument();
     if (document != null) {
       final XmlTag rootTag = document.getRootTag();
       final String externalName = getExternalName(listOwner, false);
       if (rootTag != null) {
         for (XmlTag tag : rootTag.getSubTags()) {
           if (Comparing.strEqual(
               StringUtil.unescapeXml(tag.getAttributeValue("name")), externalName)) {
             for (XmlTag annTag : tag.getSubTags()) {
               if (Comparing.strEqual(annTag.getAttributeValue("name"), annotationFQName)) {
                 annTag.delete();
                 break;
               }
             }
             tag.add(
                 XmlElementFactory.getInstance(myPsiManager.getProject())
                     .createTagFromText(createAnnotationTag(annotationFQName, values)));
             return;
           }
         }
         @NonNls String text = "<item name=\'" + StringUtil.escapeXml(externalName) + "\'>\n";
         text += createAnnotationTag(annotationFQName, values);
         text += "</item>";
         rootTag.add(
             XmlElementFactory.getInstance(myPsiManager.getProject()).createTagFromText(text));
       }
     }
   } catch (IncorrectOperationException e) {
     LOG.error(e);
   } finally {
     dropCache();
     if (codeUsageFile.getVirtualFile().isInLocalFileSystem()) {
       UndoUtil.markPsiFileForUndo(codeUsageFile);
     }
   }
 }
 private ASTNode expandTag() throws IncorrectOperationException {
   ASTNode endTagStart = XmlChildRole.CLOSING_TAG_START_FINDER.findChild(this);
   if (endTagStart == null) {
     final XmlTagImpl tagFromText =
         (XmlTagImpl)
             XmlElementFactory.getInstance(getProject())
                 .createTagFromText("<" + getName() + "></" + getName() + ">");
     final ASTNode startTagStart = XmlChildRole.START_TAG_END_FINDER.findChild(tagFromText);
     endTagStart = XmlChildRole.CLOSING_TAG_START_FINDER.findChild(tagFromText);
     final LeafElement emptyTagEnd =
         (LeafElement) XmlChildRole.EMPTY_TAG_END_FINDER.findChild(this);
     if (emptyTagEnd != null) removeChild(emptyTagEnd);
     addChildren(startTagStart, null, null);
   }
   return endTagStart;
 }
  public XmlAttribute setAttribute(String qname, String value) throws IncorrectOperationException {
    final XmlAttribute attribute = getAttribute(qname);

    if (attribute != null) {
      if (value == null) {
        deleteChildInternal(attribute.getNode());
        return null;
      }
      attribute.setValue(value);
      return attribute;
    } else if (value == null) {
      return null;
    } else {
      PsiElement xmlAttribute =
          add(XmlElementFactory.getInstance(getProject()).createXmlAttribute(qname, value));
      while (!(xmlAttribute instanceof XmlAttribute)) xmlAttribute = xmlAttribute.getNextSibling();
      return (XmlAttribute) xmlAttribute;
    }
  }