How to externalise and internalise

For a class TX defined as:

class TX
      {
public:
      ...
      void ExternalizeL(RWriteStream& aStream) const;
      void InternalizeL(RReadStream& aStream);
      ...
      };

an instance of TX can be externalised to the stream outstream, by calling the ExternalizeL() member function of TX:

    ...
    TX object;
    ...
    object.ExternalizeL(outstream);
    ...

An alternative, and better way, is to use the templated stream operator<<. The Store framework implements this by calling TX::ExternalizeL(). The syntax is simply:

    ...
    outstream << object; // externalise object
    ...

Similarly, the TX object can be internalised from the stream instream, by calling the InternalizeL() member function of TX:

    TX object;
       ...
    object.InternalizeL(instream);
    ...

The templated stream operator>> can also be used. The Store framework implements this by calling TX::InternalizeL(). The syntax is simply:

instream >> object; // internalise object