code: protected function checkContentTypeHeader(HeaderParametersInterface $parameters)
      {
          // Do not allow specify more than 1 media type for input data. Otherwise which one is correct?
          if (count($parameters->getContentTypeHeader()->getMediaTypes()) > 1) {
              throw new E([$this->createMultipleMediaTypesError()], E::HTTP_CODE_BAD_REQUEST);
          }
  
          $this->codecMatcher->matchDecoder($parameters->getContentTypeHeader());
  
          // From spec: Servers MUST respond with a 415 Unsupported Media Type status code
          // if a request specifies the header Content-Type: application/vnd.api+json with
          // any media type parameters.
  
          // We return 415 if no match found for decoder (media type with or wo parameters)
          // If no decoders were configured for media types with parameters we return 415 anyway
          if ($this->codecMatcher->getDecoderHeaderMatchedType() === null) {
              throw new E([$this->createUnsupportedMediaTypeError()], E::HTTP_CODE_UNSUPPORTED_MEDIA_TYPE);
          }
      }
docs: @param HeaderParametersInterface $parameters
  
  @return void