@Override
  @Nullable
  @Nls
  public String getConfigFileErrorMessage(final ConfigFile configFile) {
    if (configFile.getVirtualFile() == null) {
      String path = FileUtil.toSystemDependentName(VfsUtilCore.urlToPath(configFile.getUrl()));
      return JavaCompilerBundle.message("mesage.text.deployment.descriptor.file.not.exist", path);
    }
    PsiFile psiFile = configFile.getPsiFile();
    if (psiFile == null || !psiFile.isValid()) {
      return JavaCompilerBundle.message("message.text.deployment.description.invalid.file");
    }

    if (psiFile instanceof XmlFile) {
      XmlDocument document = ((XmlFile)psiFile).getDocument();
      if (document == null || document.getRootTag() == null) {
        return JavaCompilerBundle.message("message.text.xml.file.invalid", FileUtil.toSystemDependentName(
          VfsUtilCore.urlToPath(configFile.getUrl())));
      }
    }
    return null;
  }
@Override
  @Nullable
  @Nls
  public String getConfigFileErrorMessage(final ConfigFile configFile)