JAVA GIS方法表现不正常

Question

I am using a method call to transform a Point in one spatial reference to another (one coordinate plane to another basically) and the call works fine in the first example, then in the second example I am using the same method on the same object type and the method has no effect on the Point... code and an example below: (the midpoint.project(GeometryUtil.getLatLongCoordSystem)) is the method call I am having issues with)

//works fine...

if (closestStationOrSpanFw != null) {
                IGeometry shape = closestStationOrSpanFw.getIFeature().getShapeCopy();
                Point point = null;
                if (shape instanceof Point) {
                    point = (Point) shape;
                    System.out.println("OLD POINT coords: " + point.getX() + "        " + point.getY());
                    point.project(GeometryUtil.getLatLongCoordSystem());
                    System.out.println("NEW POINT coords: " + point.getX() + "        " + point.getY());


//Problem code:

else if (shape instanceof Polyline){
                    Polyline line = (Polyline) shape;
                    Point lowerLeft = (Point) line.getEnvelope().getLowerLeft();
                    Point upperRight = (Point) line.getEnvelope().getUpperRight();
                    Point midpoint = GeometryUtil.getMidpoint(lowerLeft, upperRight);
                    System.out.println("OLD LINE coords: " + midpoint.getX() + "        " + midpoint.getY());
                    midpoint.project(GeometryUtil.getLatLongCoordSystem());
                    System.out.println("NEW LINE coords: " + midpoint.getX() + "        " + midpoint.getY());

output of the properly working Point System.outs:

OLD POINT coords: 1860356.9240645461        1698342.0271777364
NEW POINT coords: -87.85965314497173        34.6678477163251

output of the broken Polyline System.outs (very close to point coordinate above):

OLD LINE coords: 1860490.636483086        1698315.1646775191
NEW LINE coords: 1860490.636483086        1698315.1646775191

As you can see, this seems to work properly in the first case but not in the second. Any ideas?

Answer 1

The documentation states that "to Project, the geometry needs to have a Spatial Reference set, and not have an UnknownCoordinateSystem. The new spatial reference system passed to the method defines the output coordinate system. If either spatial reference is Unknown, the coordinates are not changed. The Z and measure values are not changed by the Project method"

Your second point probably doesn't have a spatial reference set. Setting it should fix it.