[Geotools-gt2-users] featureCollection.subCollection(filter)

[<sa...@df...>]

Hello,

I'm still a bit new to geotools. I want to extract features out of one
Featurecollection into a new FeatureCollection. To do this, I use a =
bounding
box geometry filter. This filter is build like shown in the tutorial. =
But
the subcollection I get in return is empty. If I build the new
FeatureCollection manually, it contains two features.

The following code snippet shows what I'm doing:
      ...
	FeatureIterator it =3D fc1.features();
      FeatureIterator it2 =3D fc2.features();
      Feature f =3D null;
      Feature f2 =3D null;
      FeatureCollection includes =3D null;
     =20
      while(it.hasNext()){
		f =3D it.next();
           =20
            //build filter
            Envelope envelope =3D f.getBounds();
            //envelope =3D f.getDefaultGeometry().getEnvelopeInternal();
            FilterFactory ff =3D =
FilterFactoryFinder.createFilterFactory();
            Expression bbox;
            Expression geometry =3D ff.createAttributeExpression( =
"the_geom"
);
            GeometryFilter bboxFilter;
            try {
                bbox =3D ff.createBBoxExpression( envelope );
                bboxFilter =3D
ff.createGeometryFilter(AbstractFilter.GEOMETRY_BBOX);
                bboxFilter.addLeftGeometry( geometry );
                bboxFilter.addRightGeometry( bbox );
            } catch (IllegalFilterException e) {
                throw (RuntimeException) new RuntimeException( =
).initCause(
e );
            }
            //build new featureCollection using filter
            includes =3D fc2.subCollection(bboxFilter);
            //now the collection is empty
            System.out.println(includes.size());

            //build new featureCollection manually:
            DefaultFeatureCollections dfc =3D new =
DefaultFeatureCollections();
            includes =3D dfc.newCollection();
            while (it2.hasNext()) {
                f2 =3D it2.next();
=20
//if(f.getDefaultGeometry().intersects(f2.getDefaultGeometry())){
                if(f.getBounds().intersects(f2.getBounds())){
                    includes.add(f2);
                }
            }
            it2.close();
            //now the collection contains two features
            System.out.println(includes.size());
      }
      it.close();
      ...

Has someone ideas, why the results differ? Your help would be much
appreciated!

Regards,
Kerstin S=E4lzer