AsEncodedPolyline Class Reference

Inheritance diagram for AsEncodedPolyline:

Collaboration diagram for AsEncodedPolyline:

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

Static Public Member Functions
static String	encodePolyline (final LineString linestring)

Static Private Member Functions
static void	encode (long v, StringBuffer result)

Member Function Documentation

encode()

static void encode ( long  v, StringBuffer  result  )

staticprivate

Referenced by AsEncodedPolyline.encodePolyline().

                                                            {
        v = v < 0 ? ~(v << 1) : v << 1;
        while (v >= 0x20) {
            result.append(Character.toChars((int) ((0x20 | (v & 0x1f)) + 63)));
            v >>= 5;
        }
        result.append(Character.toChars((int) (v + 63)));
    }

encodePolyline()

static String encodePolyline ( final LineString  linestring )

static

References AsEncodedPolyline.encode().

Referenced by AsEncodedPolyline.operation().

                                                                         {
        long lastLat = 0;
        long lastLng = 0;

        final StringBuffer result = new StringBuffer();

        for (final Coordinate point : linestring.getCoordinates()) {
            long lat = Math.round(point.x * 1e5);
            long lng = Math.round(point.y * 1e5);

            long dLat = lat - lastLat;
            long dLng = lng - lastLng;

            encode(dLat, result);
            encode(dLng, result);

            lastLat = lat;
            lastLng = lng;
        }
        return result.toString();
    }

evaluate()

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

inherited

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

                                                                                                            {
                if (args.length != 1) {
                        throw new ValueExprEvaluationException(getURI() + " requires exactly 1 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());
                        String result = operation(geom);
                        return valueFactory.createLiteral(result);
                }
                throw new ValueExprEvaluationException("Argument given is not a geometry literal");
                
        }

getURI()

String getURI

(

)

References POSTGIS.ST_ASENCODEDPOLYLINE.

                               {
                return POSTGIS.ST_ASENCODEDPOLYLINE.stringValue();
        }

operation()

String operation

(

Geometry

geom

)

References AsEncodedPolyline.encodePolyline().

                                               {
                if (geom instanceof LineString) {
                String result=encodePolyline((LineString)geom);
                return result;
        }
                return null;
        }