LongestLine Class Reference

Inheritance diagram for LongestLine:

Collaboration diagram for LongestLine:

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

Protected Member Functions
Geometry	relation (Geometry geom1, Geometry geom2)

Member Function Documentation

evaluate()

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

inherited

                                                                                                            {
                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 transformed=LiteralUtils.transform(geom2, geom);
                        Geometry result = relation(geom,transformed);
                        return valueFactory.createLiteral(((VectorLiteral) l).unparse(result),((Literal)args[0]).getDatatype());
                }
                throw new ValueExprEvaluationException("Arguments given are not geometry literals");
        }

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

Referenced by LongestLineTest.testLongestLine(), ShortestLineTest.testShortestLine(), and ShortestLine3DTest.testShortestLine3D().

getURI()

String getURI

(

)

                               {
                return POSTGIS.st_longestLine.stringValue();
        }

References POSTGIS.st_longestLine.

relation()

Geometry relation ( Geometry  geom1, Geometry  geom2  )

protected

Reimplemented from GeometricRelationModifierFunction.

                                                                    {
                Double maxDistance=0.;
        Coordinate maxCoord1=null;
        Coordinate maxCoord2=null;
                for(Coordinate coord:geom1.getCoordinates()) {
                        for(Coordinate coord2:geom2.getCoordinates()) {
                                Double curdistance=coord.distance(coord2);
                                if(curdistance>maxDistance) {
                                        maxDistance=curdistance;
                                        maxCoord1=coord;
                                        maxCoord2=coord2;
                                }
                        }
                }
                return LiteralUtils.createGeometry(new Coordinate[] {maxCoord1,maxCoord2},"LineString", geom1.getSRID());
        }

References LiteralUtils.createGeometry().