StartPoint Class Reference

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)

Member Function Documentation

evaluate()

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

inherited

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

                                                                                                            {
                if (args.length != 2) {
                        throw new ValueExprEvaluationException(getURI() + " requires exactly 2 arguments, 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");
        }

getURI()

String getURI

(

)

References POSTGIS.st_startPoint.

                               {
                return POSTGIS.st_startPoint.stringValue();
        }

operation()

Geometry operation ( Geometry  geom )

protected

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

        }