True, if you have the case of one very large GML layer for your whole
map, but this is far from normal GIS.

Larry

On 8/30/07, Sunburned Surveyor <[EMAIL PROTECTED]> wrote:
> Paul is correct. The pull parser does not reduce the memory of the
> parsing results, but it does reduce the memory used during the parsing
> process. That is because an in-memory representation of the entire XML
> document is not constructed.
>
> One advantage of this is using the parser to select only data within
> the XML file that meets specific criteria. For example, if we had a
> 50MB SGF file representing the city of Stockton, I could parse the
> file and create only building features, even thought the file might
> contain road features, landmark features, park features. etc.
> In fact, I could even parse the file and only create features for
> buildings whose "building type" attribute was set to "Public". This
> allows me to extract the information I want without reading all 50 MB
> into memory.
>
> The Sunburned Surveyor
>
> On 8/30/07, Paul Austin <[EMAIL PROTECTED]> wrote:
> > Hi Larry,
> >
> > You are correct that the resulting data set will take up a lot of memory
> > at the end, the advantage with the pull parser is that you don't take up
> > a whole bunch of extra memory for the XML DOM structures which typically
> > get loaded into memory for the whole document. So with the pull parser
> > there is little memory overhead where as for DOM you have probably at
> > least 2x memory required to load if not more
> >
> > Paul
> >
> > Larry Becker wrote:
> > > It isn't the parser that takes up the memory except temporarily), but
> > > the memory resident dataset after loading.  This will still limit the
> > > size.
> > >
> > > Larry
> > >
> > > On 8/30/07, Sunburned Surveyor <[EMAIL PROTECTED]> wrote:
> > >
> > >> Yup. It makes you wonder why they didn't use pull parsers from the
> > >> very beginning, doesn't it.
> > >>
> > >> SS
> > >>
> > >> On 8/30/07, Paul Austin <[EMAIL PROTECTED]> wrote:
> > >>
> > >>> Agreed the pull parser is the only way to go for large XML files
> > >>>
> > >>> Paul
> > >>>
> > >>> Sunburned Surveyor wrote:
> > >>>
> > >>>> Martin,
> > >>>>
> > >>>> If we decide to support a restricted form of GML 2 we could build our
> > >>>> reader and writer on top of the XML Pull Parser from Sun. This would
> > >>>> help us to avoid memory problems when reading in large files.
> > >>>>
> > >>>> https://sjsxp.dev.java.net/
> > >>>>
> > >>>> Just a thought.
> > >>>>
> > >>>> The Sunburned Surveyor
> > >>>>
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