Yes, I have looked at the various newer versions of the GeoTools
Shapefile readers.  They seemed to be too complicated to be a drop in
replacement for our older GeoTools version (which also has the
capability to randomly read, but that is useless in OJ's
implementation).

Larry


On 8/30/07, Sunburned Surveyor <[EMAIL PROTECTED]> wrote:
> Larry,
>
> I don't know if it is of interest to you, but GeoTools has a streaming
> ESRI Shapefile parser. They actually have the ability to randomly
> access an indexed Shapefile. I plan on using their Shapefile code in
> my FeatureCache. The idea is to use the GeoTools code to access one
> Feature at a time from the Shapefile, storing this Feature in the
> FeatureCache.
>
> SS
>
> On 8/30/07, Larry Becker <[EMAIL PROTECTED]> wrote:
> > >At one point I actually rewrote the Shapefile parser to be streaming as 
> > >well...
> >
> > I guess I hadn't actually realized it wasn't until now.  Do you
> > remember what happened to the code, or why you didn't stay with the
> > streaming version?  A very large shape file seems like a more likely
> > scenario that I actually care about.
> >
> > Larry
> > On 8/30/07, Martin Davis <[EMAIL PROTECTED]> wrote:
> > > This would be especially important if you had multiple
> > > FeatureCollections stored in one file, and you wanted to load only one
> > > of them.
> > >
> > > Sunburned Surveyor 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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> > >
> > > --
> > > Martin Davis
> > > Senior Technical Architect
> > > Refractions Research, Inc.
> > > (250) 383-3022
> > >
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