From: thomas at tada.se (Thomas Hallgren)
Date: Fri, 29 Sep 2006 16:06:01 +0200
Subject: [Pljava-dev] VarLenTuple example code
In-Reply-To: <451D2198.7050202@logix-tt.com>
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Message-ID: <451D2849.8030109@tada.se>

Hi Markus,
OK, now I think I finally understand what it is you are trying to hammer 
through my thick skull :-)

You are saying that two mechanisms are not enough. We need:

The text (canonical) to disc conversion (the current input/output)
The external binary (canonical) format (used in various protocols) to 
disc conversion (the send/receive).
A way to create Java objects from canonical binary format.
A way to create the canonical binary format from Java objects.

Then it all falls into place. This is what I think needs to be done:

1. We need two new methods. One that does the C -> B conversion and one 
that does the B -> C. I.e. verbatim Java implementations of the 
send/receive. Those methods should be static since this is a byte[] to 
byte[] conversion only.
2. The readSQL methods should be called with an SQLInput that wraps the 
output of the C -> B converter.
3. The data written by the writeSQL method should be passed to the B -> 
C converter.

And of course, Java really comes into play when a COPY is performed 
since the B -> C and C ->B must be executed.

Sorry for being so thick-headed.

Kind Regards,
Thomas Hallgren