[geotk] coordinate transformation from 3857 to 4326

[juergen sorg]

hi,

i have a question about transforming coordinates from epsg:3857 (google) 
to epsg:4326 (lon lat). (i am not sure if this is the right place to ask 
for - but i am using geotk with jts).
in [0] you can find a code snippet to transform a point and in [1] the 
results.
my questions are:

1. why are the coordinates not swapped, because after the transformation 
x-coord and the y-coord are at the wrong place.
2. do i have to swap it by my own and if yes then how can i do it with 
e.g. polygons
3. why the crs is still 3857 after transformation (it should 4326) and 
if i have to change it by my own how this can be accomplished?

thanks in advance

regards,
juergen



[0]

WKTReader WKT_READER = new WKTReader(
				new GeometryFactory(new PrecisionModel(PrecisionModel.FLOATING), 3857));
		String pt_google="POINT(704377.78268943 6533181.663612)";
		Geometry pt_google_geom=WKT_READER.read(pt_google);
		
		Geometry pt_wgs84_geom=JTS.transform(pt_google_geom,
				CRS.findOperation(CRS.forCode("EPSG:3857"), 
CRS.forCode("EPSG:4326"), null).getMathTransform());
		Geometry pt_google_geom_transformed=JTS.transform(pt_wgs84_geom,
				CRS.findOperation(CRS.forCode("EPSG:4326"), 
CRS.forCode("EPSG:3857"), null).getMathTransform());
System.out.println(pt_google_geom);
System.out.println(pt_google_geom.getSRID());
System.out.println(pt_wgs84_geom);
System.out.println(pt_wgs84_geom.getSRID());
System.out.println(pt_google_geom_transformed); 
System.out.println(pt_google_geom_transformed.getSRID());
		

[1]

POINT (704377.78268943 6533181.663612)
3857
POINT (50.499200582184564 6.327533279841338)
3857
POINT (704377.7826894299 6533181.663611999)
3857

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