StartPoint Class Reference

Returns the first point of the given geometry. More...

Inheritance diagram for StartPoint:

Collaboration diagram for StartPoint:

Public Member Functions
String	getURI ()
Value	evaluate (ValueFactory valueFactory, Value... args) throws ValueExprEvaluationException

Protected Member Functions
Geometry	operation (Geometry geom)

Detailed Description

Returns the first point of the given geometry.

Member Function Documentation

evaluate()

Value evaluate ( ValueFactory  valueFactory, Value...  args  ) throws ValueExprEvaluationException

inherited

                                                                                                            {
                if (args.length != 1) {
                        throw new ValueExprEvaluationException(getURI() + " requires exactly 1 argument, got " + args.length);
                }
                
                LiteralType l=LiteralRegistry.getLiteral(((Literal)args[0]).getDatatype().toString());
                if(l instanceof VectorLiteral) {
                        Geometry geom=((VectorLiteral)l).read(args[0].stringValue());
                        Geometry result = operation(geom);
                        return valueFactory.createLiteral(((VectorLiteral) l).unparse(result),((Literal)args[0]).getDatatype());
                }
                throw new ValueExprEvaluationException("Argument given is not a geometry literal");
        }

References LiteralRegistry.getLiteral(), and GeometricUnaryFunction.operation().

Referenced by BoundaryTest.testBoundary(), BoundingDiagonalTest.testBoundingDiagonal(), CentroidTest.testCentroid(), StartPointTest.testCircularString(), CircumcentreTest.testCircumcentre1(), CollectionHomogenizeTest.testCollectionHomogenize(), FlipCoordinatesTest.testFlipCoordinates(), Force2DTest.testForce2D(), Force3DTest.testForce3D(), Force3DMTest.testForce3DM(), Force3DMTest.testForce3DM2(), Force4DTest.testForce4D(), ForceCollectionTest.testForceCollection(), ForceCollectionTest.testForceCollectionZ(), ForcePolygonCCWTest.testForcePolygonCCW(), ForcePolygonCWTest.testForcePolygonCW(), EndPointTest.testLineString2D(), StartPointTest.testLineString2D(), EndPointTest.testLineString3D(), StartPointTest.testLineString3D(), MinimumBoundingCircleCenterTest.testMinimumBoundingCircle(), MinimumBoundingCircleTest.testMinimumBoundingCircle(), MinimumClearanceLineTest.testMinimumClearanceLine(), MinimumDiameterLineTest.testMinimumDiameterLine(), MinimumRectangleTest.testMinimumRectangle(), MultiTest.testMulti2D(), MultiTest.testMulti3D(), SelfIntersectionsTest.testNoSelfIntersections(), EndPointTest.testPoint(), StartPointTest.testPoint(), PointsTest.testPoints(), PointsTest.testPoints3D(), ReverseTest.testReverse(), SelfIntersectionsTest.testSelfIntersections(), ShiftLongitudeTest.testShiftLongitude(), SimplifyPreserveTopologyTest.testSimplifyVW(), and TransScaleTest.testTransScale().

getURI()

String getURI

(

)

                               {
                return POSTGIS.st_startPoint.stringValue();
        }

References POSTGIS.st_startPoint.

operation()

Geometry operation ( Geometry  geom )

protected

Reimplemented from GeometricUnaryFunction.

                                                    {
                if (geom instanceof LineString) {
            Point point = ((LineString) geom).getStartPoint();
            return point;
        }else if(geom instanceof Point) {
                return geom;
        }
                return null;
 
        }