@Override
    public Object getDocument(String url) {
        final VirtualFile virtualFile = VfsUtilCore.findRelativeFile(url, file.getVirtualFile());
        if (virtualFile != null) {
            final PsiFile file = this.file.getManager().findFile(virtualFile);
            if (file instanceof XmlFile) {
                return ((XmlFile)file).getDocument();
            }
        }
        return null;
    }
@Override
    public Object getDocument(String url)