@Nullable
  @NlsSafe
  private static String getGradleVersion(VirtualFile[] libraryFiles) {
    for (VirtualFile file : libraryFiles) {
      final String version = getGradleJarVersion(file);
      if (version != null) {
        return version;
      }
    }
    return null;
  }
@Nullable
  @NlsSafe
  private static String getGradleVersion(VirtualFile[] libraryFiles)