code: public <S, T> ToMarshaller<S, T> findMarshaller(ConverterKey<S,T> key) {
  
  		Converter<S,T> converter = findConverter(key);
  		
  		if (converter == null) {
  			return null;
  		}
  		
  		if (ToMarshallerConverter.class.isAssignableFrom(converter.getClass())) {
  			return ((ToMarshallerConverter<S, T>)converter).getMarshaller();
  		} else {
  			return new ConverterToMarshaller<S, T>(converter);
  		}
  	}
docs: Resolve a Marshaller with the given source and target class.
  The marshaller is used as follows: Instances of the source can be marshalled into the target class.
  @param key The key to look up