ReverseRing Class Reference

Reverses the coordinates of a given ring of a polygon. More...

Inheritance diagram for ReverseRing:

Collaboration diagram for ReverseRing:

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

Protected Member Functions
Geometry	relation (Geometry geom, Integer value)

Detailed Description

Reverses the coordinates of a given ring of a polygon.

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);
                }               
                
                Integer value=Integer.valueOf(args[1].stringValue());
                LiteralType l=LiteralRegistry.getLiteral(((Literal)args[0]).getDatatype().toString());
                if(l instanceof VectorLiteral) {
                        Geometry geom=((VectorLiteral)l).read(args[0].stringValue());
                        Geometry result = relation(geom,value);
                        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 GeometricModifierIntegerFunction.relation().

Referenced by CollectionExtractTest.testCollectionExtract(), GeneratePointsTest.testGeneratePoints(), PointNTest.testLineString(), PrecisionReducerTest.testPrecisionReducer(), RemovePointTest.testRemovePoint(), RemovePointTest.testRemovePointZ(), RemoveRingTest.testRemoveRing(), and ReverseRingTest.testReverseRing().

getURI()

String getURI

(

)

                               {
                return POSTGIS.st_reverseRing.toString();
        }

References POSTGIS.st_reverseRing.

relation()

Geometry relation ( Geometry  geom, Integer  value  )

protected

Reimplemented from GeometricModifierIntegerFunction.

                                                                  {
                if(geom instanceof Polygon) {
                        Polygon poly=(Polygon) geom;
                        if(value<0 || value>poly.getNumInteriorRing()) {
                                return geom;
                        }
                        List<LinearRing> rings=new LinkedList<LinearRing>();
                        for(int i=0;i<poly.getNumInteriorRing();i++) {
                                if(i==value) {
                                        List<Coordinate> newring=new LinkedList<Coordinate>();
                                        for(int j=poly.getInteriorRingN(i).getCoordinates().length-1;j>=0;j--) {
                                                newring.add(poly.getInteriorRingN(i).getCoordinateN(j));
                                        }
                                        GeometryFactory fac=new GeometryFactory();
                                        rings.add(fac.createLinearRing(newring.toArray(new Coordinate[0])));
                                }else {
                                        rings.add((LinearRing)poly.getInteriorRingN(i));
                                }
                        }
                        GeometryFactory fac=new GeometryFactory();
                        return fac.createPolygon((LinearRing)poly.getExteriorRing(), rings.toArray(new LinearRing[0]));
                }
                return null;
        }