ShortestLine Class Reference

Inheritance diagram for ShortestLine:

Collaboration diagram for ShortestLine:

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

Protected Member Functions
Geometry	relation (Geometry g1, Geometry g2)

Member Function Documentation

evaluate()

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

inherited

References LiteralRegistry.getLiteral(), and GeometricRelationModifierFunction.relation().

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

                LiteralType l=LiteralRegistry.getLiteral(((Literal)args[0]).getDatatype().toString());
                LiteralType l2=LiteralRegistry.getLiteral(((Literal)args[1]).getDatatype().toString());
                if(l instanceof VectorLiteral) {
                        Geometry geom=((VectorLiteral)l).read(args[0].stringValue());
                        Geometry geom2=((VectorLiteral)l2).read(args[1].stringValue());
                        Geometry result = relation(geom,geom2);
                        return valueFactory.createLiteral(((VectorLiteral) l).unparse(result),((Literal)args[0]).getDatatype());
                }
                throw new ValueExprEvaluationException("Arguments given are not geometry literals");
        }

getURI()

String getURI

(

)

References POSTGIS.st_shortestLine.

                               {
                return POSTGIS.st_shortestLine.stringValue();
        }

relation()

Geometry relation ( Geometry  g1, Geometry  g2  )

protected

References LiteralUtils.createGeometry(), and LiteralUtils.transform().

                                                              {
                 Geometry transformed=LiteralUtils.transform(g2, g1);
                 DistanceOp distop = new DistanceOp(g1, transformed);
         Coordinate[] coord = distop.nearestPoints();
         return LiteralUtils.createGeometry(coord, "LINESTRING", g1.getSRID());
        }