Kza wrote:
> Feature 1: A progress display.

The SAX APIs can be persuaded to give line/column information, though 
unless you know how many lines there were in the file before you stared 
parsing it that doesn't do you any good. Look at the Locator API.

The DOM assumes reading the file is a single operation, so the concept 
of getting incremental details doesn't make much sense. You *could* plug 
in a stream filter between wherever the file is being read from and the 
parser, and set up that filter so it counts characters going by -- 
that's going to give you only a very rough progress indication, and 
again it requires that you know the length before you start if you want 
to report it as a percentage-complete number.

> Feature 2: Loading only a "screenful" of the file at a time.

"Screenful" is not defined in XML. Nor is starting parse from the middle 
of a file. You could try to do something with incremental processing, 
via throttling of ta SAX stream -- I've done that in the past -- but 
keeping track of when enough has been read to fill a screen and when 
more would have to be read to fill the next screen is very much an 
application problem rather than a parser problem.

Random-access to an XML model isn't a problem -- the DOM can do that, 
though again it isn't designed to operate on screenfuls -- but 
random-order parsing really doesn't make sense. Namespaces are 
context-dependent, to take one major point where that idea breaks down.


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() ASCII Ribbon Campaign  | Joe Kesselman
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