code: private JsonWriter newJsonWriter(Writer writer) throws IOException {
      if (generateNonExecutableJson) {
        writer.write(JSON_NON_EXECUTABLE_PREFIX);
      }
      JsonWriter jsonWriter = new JsonWriter(writer);
      if (prettyPrinting) {
        jsonWriter.setIndent("  ");
      }
      jsonWriter.setSerializeNulls(serializeNulls);
      return jsonWriter;
    }
docs: Returns a new JSON writer configured for this GSON and with the non-execute
  prefix if that is configured.