@NotNull
  public static String addToPathEnvVar(@Nullable String source, @NotNull String value, boolean asPrefix) {
    if (StringUtil.isEmpty(source)) return value;
    Set<String> paths = Sets.newHashSet(source.split(File.pathSeparator));
    if (!paths.contains(value)) {
      if (asPrefix) {
        return value + File.pathSeparator + source;
      }
      else {
        return source + File.pathSeparator + value;
      }
    }
    else {
      return source;
    }
  }
@NotNull
  public static String addToPathEnvVar(@Nullable String source, @NotNull String value, boolean asPrefix)