Re: [Geotools-gt2-users] Newbie Question: How to identify Feature in Shapefile contains a Point

[Jody G. <jga...@re...>]

Cliff Darling wrote:
> I want to identify if a given latitude/longitude coordinate lies 
> within any of the features within the shapefile.
Question; is your shapefile also measured in lat/long? Or is it measured 
in something else? You can tell because the shapefile will have a ".prj" 
file :-)
> So far, I am able to load in the Shape File and iterate through the 
> features with Feature Iterator.  I tried to do my comparison by 
> creating a Point through a GeometryFactory from the latitude/longitude 
> values I have, and then trying:
>
> feature.getDefaultGeometry().contains(thePoint).
>
> However, this is always false.
That seems correct.
> The lat/long values I have are:
>
> 26.49247
> -80.47114
>
> Is there some additional step I need to do?  Do these values need to 
> be converted in some fashion before performing the geometry operation 
> (contains())?
The values; and your geometry should both be in the same "coordinate 
reference system" (ie they should be measuring the same thing).

Have a look here:
- http://docs.codehaus.org/display/GEOTDOC/02+JTS+Utility+Class

Note you can also set up a "query" and only ask for the features that 
contain your point:
- http://docs.codehaus.org/display/GEOTDOC/Filter+Examples
- http://docs.codehaus.org/display/GEOTDOC/06+FeatureSource
> Please let me know if I should be asking a different question.  I am 
> feeling my way through this right now.
Best of luck
Jody