자바 geotools 15.1 좌표 변환

import org.geotools.geometry.jts.JTS;
import org.geotools.geometry.jts.JTSFactoryFinder;
import org.geotools.referencing.CRS;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import org.opengis.referencing.operation.MathTransform;

import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;
import com.vividsolutions.jts.geom.Point;

public class GeoTransTest { 

 private CoordinateReferenceSystem sourceCRS;
 private CoordinateReferenceSystem targetCRS;
 
 public GeoTransTest(String sourceCRS, String targetCRS) throws Exception {
  this.sourceCRS = CRS.decode(sourceCRS);
  this.targetCRS = CRS.decode(targetCRS);
  
 }
 
 public void transform(String x, String y) throws Exception {
  
  GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
  Coordinate coord = new Coordinate(Double.parseDouble(x), Double.parseDouble(y));
  Geometry sourceGeometry = geometryFactory.createPoint(coord);
  
  MathTransform transform = CRS.findMathTransform(sourceCRS, targetCRS);
  
  Geometry targetGeomery = JTS.transform(sourceGeometry, transform);
  Point targetPoint = targetGeomery.getCentroid();

  System.out.println("변환전 EPSG:4326(WGS84) X : "+x + "\t EPSG:4326(WGS84) Y : "+y);
  System.out.println("변환후 EPSG:3857 X : "+targetPoint.getX() + "\t EPSG:3857 Y : "+targetPoint.getY());
  
 } 
 
 public static void main(String[] args) throws Exception {
  
  GeoTransTest g = new GeoTransTest("EPSG:4326", "EPSG:3857");

  g.transform("37.5639686", "126.9794393");
     
 }

}