docs: public void marshall(Source source, ProtocolMarshaller protocolMarshaller) {
  
          if (source == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(source.getType(), TYPE_BINDING);
              protocolMarshaller.marshall(source.getUrl(), URL_BINDING);
              protocolMarshaller.marshall(source.getUsername(), USERNAME_BINDING);
              protocolMarshaller.marshall(source.getPassword(), PASSWORD_BINDING);
              protocolMarshaller.marshall(source.getSshKey(), SSHKEY_BINDING);
              protocolMarshaller.marshall(source.getRevision(), REVISION_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }