import java.awt.geom.Point2D;
import java.math.BigDecimal;
import java.math.RoundingMode;

import org.geotoolkit.referencing.GeodeticCalculator;


public class TestGeotoolkit {

    /**
     * @param args
     */
    public static void main(String[] args) {
        
        double sourceLocLon = 121.5386;
        double sourceLocLat = 38.965667;
        
        double targetLocLon = -58.817222;
        double targetLocLat = -38.483056; 
        
        //MAX DISTANCE in KM: 19983.171
        
        Point2D startingPoint = new Point2D.Double(sourceLocLon, sourceLocLat);
        Point2D destinationPoint = new Point2D.Double(targetLocLon, targetLocLat);

        GeodeticCalculator calc = new GeodeticCalculator();
        System.out.println(String.format("Setting starting point to: LG %.5f, LT %.5f", startingPoint.getX(), startingPoint
            .getY()));
        calc.setStartingGeographicPoint(startingPoint);
        System.out.println(String.format("Setting destination point to: LG %.5f, LT %.5f", destinationPoint.getX(),
            destinationPoint.getY()));
        calc.setDestinationGeographicPoint(destinationPoint);

        BigDecimal distanceInKilometers = new BigDecimal(calc.getOrthodromicDistance() / 1000);
        distanceInKilometers = distanceInKilometers.setScale(3, RoundingMode.CEILING);
        System.out.println("Distance in KM: " + distanceInKilometers.toString());

    }
}