Re: [Geotools-devel] Re: VPF DataStore Feedback and QA

[John M. <joh...@so...>]

>>I've had a few problems that I've had to work around in my code.  All
>>these are documented in Jira under the VPF component.  The big
>>problem
>>is with files not being closed properly.  I've got a fix for it, but
>>it's kind of hacky (I have a timer in VPFFile that automatically
>>closes
>>the file if it hasn't been accessed for a while).
> 
> Hacky's usually better than nothing, in my opinion...

I checked in a couple of fixes for
http://jira.codehaus.org/browse/GEOT-454 (basically close all files when
the VPFFeatureReader is closed).  I opened a new issue for the problem
of having too many files open during a single FeatureReader invocation (
http://jira.codehaus.org/browse/GEOT-498 ) and attached the hacky patch
that fixes it.  If it looks good to everyone I can go ahead and commit
it.  I've been running with it for a few months without problem.


>>>http://jira.codehaus.org/browse/GEOT-495 – creating features with
...
>>I was never really sure what the namespaces were for so I don't make
>>any
>>use of them.  I'll defer to others to decide about this, but it
>>sounds good.
> 
> Cool.  They're basically to give better global identification to your
> features.  So your fid is your local id, and then you put it under a
> namespace, a unique uri, that says it's yours, and then you've got
> global.

Unless Jeff has any problems with this I say go ahead and commit it.


>>>http://jira.codehaus.org/browse/GEOT-496 – Bad assumptions about
>>
>>This sounds like a good fix.
> 
> Yeah, it's like 4 lines of code.  Do you want me to attach my fixes to
> the issues?

Same with this, go ahead and commit it.


>>>http://jira.codehaus.org/browse/GEOT-497 – Better FIDs.  This one
...
> Unique across the datastore should be sufficient, since like I said
> above, your datastore should have a namespace that will make it
> universally unique.  I imagine featureid + tileid would be unique
> enough.  Or you could also concat typename + featureid.

I'll see if I can get some time to look into this to see if featureid +
tileid is actually unique.  If it is then I'll go ahead and switch it to
use this.


> I think it's dnc - I think you may have actually sent it to me, or maybe
> it was Jeff.  It could be corrupted - I'll try to find some more. 
> Anyone know if there's free vpf data for Zambia?

You can get some free DNC data from http://www.nga.mil/portal/site/dnc/.
 I think they only allow downloading of the US data.  You'll need to
select a Region from the top then click on a Library Catalog link then
select a full library to download.

You can also get VMap0 from
http://www.mapability.com/index1.html?http&&&www.mapability.com/info/vmap0_download.html

Other than that I haven't found any online VPF data.


>>>Let me know what to do, and we should have a decent VPF DataStore
>>in
>>>GeoServer for the 1.3 release.
>>Good to hear.  I'm in the process of shipping the latest version of
>>our
>>software that includes VPF, Shapefile, and TIGER support.  It should
>>be
>>getting some good field testing soon.
> 
> Very cool.  Are you using the TIGER datastore in geotools?  If so, let
> me know, I don't think we include it in GeoServer yet.

TIGER has been working fine.  The best has been the VERY detailed road
data from http://www.census.gov/geo/www/maps/.

I tried to use GML but couldn't get it to work.  One problem was
http://jira.codehaus.org/browse/GEOT-471.  But even with that fixed
locally I couldn't get any downloaded files to actually work.  My guess
was that it was looking for GML tags at the root level and all the files
I found had GML tags embedded down in subelements.