void setWriterOptions(JsonWriter writer) {
      writer.setSerializeNulls(serializeNulls);
      writer.setLenient(lenient);
      writer.setHtmlSafe(htmlSafe);
      writer.setIndent(prettyPrinting ? "  " : "");
    }
Handled media types
@return media types
gson/src/org/immutables/gson/stream/GsonMessageBodyProvider.java