code: @NonNull
      public static List<String> unmodifiableNonNullListOfStrings(@Nullable Object[] args) {
          if (args == null || args.length == 0) {
              return emptyList();
          } else {
              final List<String> list = new ArrayList<String>(args.length);
  
              //noinspection ForLoopReplaceableByForEach -> on Android it's faster
              for (int i = 0; i < args.length; i++) {
                  final Object arg = args[i];
                  list.add(arg != null ? arg.toString() : "null");
              }
  
              return unmodifiableList(list);
          }
      }
docs: Converts array of objects to {@code List<String>}.
  
  @param args array objects that will be converted to list of strings.
  @return non-null, unmodifiable list of strings.