Re: [Fwd: XML/JavaBean "Coins"] (SOAP requested)

Roy T. Fielding (fielding@kiwi.ICS.uci.edu)
Tue, 23 Jun 1998 18:36:30 -0700


>>Date: 21-06-98
>>Source: InfoWorld
>>Subject: Two-faced Coins catching on
>>[...]
>>
>>Traditionally, a JavaBean object is encoded -- or serialized -- in a binary
>>form and then decoded and processed by the system that wants to run the
>>JavaBean. With Coins, the object is sent as text in XML syntax to the other
>>machine, and that machine converts it into an object, which is presumably
>>faster.

Huh? If they were talking about a syntax-tree compressed Java in binary
form I might consider that a possibilty, given the results with Oberon
[Franz, M.; Kistler, T., "Slim binaries". Communications of the ACM,
Dec. 1997, vol.40, (no.12):87-94.]. But the notion that sending an object
as text in XML syntax would somehow be faster than sending it in binary
with no markup at all is a bit ridiculous.

One performance enhancement that can be done with Java is to send it
in complete executable order, meaning that the recipient can begin
processing the applet as it is downloaded just like progressive rendering
of images.

>>"Parsing text takes much less overhead than deserializing an object," said
>>Joshua Lucas, a Web consultant in Cambridge, Mass. "I think XML is going to
>>be Java's killer app. It will let you do things Java couldn't do before."

What? XML-wrapped Java will be more Turing-complete than binary Java?

>One analyst gave this marriage of XML and Java his blessing.
>
>"This is an excellent use of XML," said JP Morgenthal, president of
>NC.Focus, in Hewlett, N.Y. "We need to represent Java objects to a much
>larger non-Java world. XML-based persistence provides that."

Oh, well, that makes perfect sense. Wrap it in XML tags and you have
more semantic information than the binary code. OTOH, you could
just use the original source code because it's a hell of a lot more
meaningful (and often less verbose) than XML tags.

I don't know about Coins, but these quotes are totally lacking a clue.

>More information on Coins can be found at http://www.jxml.com

Looking at that site would indicate that the article author and
commentators didn't understand what was being proposed. Coins appear
to be a way of separating object instances from all dependencies
in much the same way as a single web page is separated from an
entire website. If you don't have to download the whole thing at
once, you get better user-perceived performance (for the same reason
as the executable order note above) and caching. Works just fine
provided that you can execute the object without its dependencies.

But you could do the same thing easier without XML.

....Roy