/**
  * Determine the JSON encoding to use for the given content type.
  *
  * @param contentType the media type as requested by the caller
  * @return the JSON encoding to use (never {@code null})
  */
 protected JsonEncoding getJsonEncoding(MediaType contentType) {
   if (contentType != null && contentType.getCharset() != null) {
     Charset charset = contentType.getCharset();
     for (JsonEncoding encoding : JsonEncoding.values()) {
       if (charset.name().equals(encoding.getJavaName())) {
         return encoding;
       }
     }
   }
   return JsonEncoding.UTF8;
 }