Those were good suggestions.

I was thinking for each country; create a prepared geometry, or that data 
structure for a point in polygon test, and run through all of the points (or if 
you are worried load the points into a spatial index and use the polygon extent 
to pull out a small number to test against).

Jody

On 07/08/2010, at 12:32 AM, [email protected] wrote:

> I assume your geometries are stored in shape files.
> 
> Possibility 1, using SQL)
> Use a spatial sql extender like postgis, import your shape files into  
> sql tables and create a query using a sql statement with spatial  
> predicates (st_contains, st_intersects)
> 
> Possibility 2, using JAVA)
> Read your polygons from a shape file.
> Read your point from the shape file and create ONE Multpoint JTS geometry.
> Intersect the Multipoint geometry with each polygon.
> The result of the intersection is a Multipoint geometry containing all  
> points within the polygon.
> 
> Hope this helps
> 
> Quoting Andreas Schildbach <[email protected]>:
> 
>> Hi there,
>> 
>> I have got 300.000 Geo-Coordinates (European Public Transport Stops) and
>> like to determine for each of them to which country they belong -
>> preferably in Java code. Due to the sheer number of coordinates, I think
>> I cannot use one of the available web services (request limits).
>> 
>> I was pointed to GT2, but am unable to find a simple example to build
>> on. I found TM_WORLD_BORDERS-0.2 data which seems to contain the country
>> shapes I need.
>> 
>> Can you give me a pointer to some code?
>> 
>> Best regards,
>> 
>> Andreas
>> 
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