/// <summary>
/// Creates a Point using the next token in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a <Point Text>.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>Returns a Point specified by the next token in
/// the stream.</returns>
/// <remarks>
/// ParseException is thrown if an unexpected token is encountered.
/// </remarks>
private static IPoint ReadPointText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
var nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(factory.CreatePoint((Coordinate)null));
}
var c = new Coordinate(GetNextNumber(tokenizer), GetNextNumber(tokenizer));
GetNextCloser(tokenizer);
return(factory.CreatePoint(c));
}
/// <summary>
/// Creates a <see cref="GeometryCollection"/> using the next token in the stream.
/// </summary>
/// <param name="tokenizer"> Tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a GeometryCollection Text.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>
/// A <see cref="GeometryCollection"/> specified by the next token in the stream.</returns>
private static IGeometryCollection ReadGeometryCollectionText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
var nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken.Equals("EMPTY"))
{
return(factory.CreateGeometryCollection(null));
}
var geometries = new List <IGeometry>();
geometries.Add(ReadGeometryTaggedText(tokenizer));
nextToken = GetNextCloserOrComma(tokenizer);
while (nextToken.Equals(","))
{
geometries.Add(ReadGeometryTaggedText(tokenizer));
nextToken = GetNextCloserOrComma(tokenizer);
}
return(factory.CreateGeometryCollection(geometries.ToArray()));
}
/// <summary>
/// Creates a Geometry using the next token in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a <Geometry Tagged Text>.</param>
/// <returns>Returns a Geometry specified by the next token in the stream.</returns>
/// <remarks>
/// Exception is thrown if the coordinates used to create a Polygon
/// shell and holes do not form closed linestrings, or if an unexpected
/// token is encountered.
/// </remarks>
private static IGeometry ReadGeometryTaggedText(WktStreamTokenizer tokenizer)
{
tokenizer.NextToken();
var type = tokenizer.GetStringValue().ToUpper();
IGeometry geometry;
IGeometryFactory factory = new GeometryFactory();
switch (type)
{
case "POINT":
geometry = ReadPointText(tokenizer, factory);
break;
case "LINESTRING":
geometry = ReadLineStringText(tokenizer, factory);
break;
case "MULTIPOINT":
geometry = ReadMultiPointText(tokenizer, factory);
break;
case "MULTILINESTRING":
geometry = ReadMultiLineStringText(tokenizer, factory);
break;
case "POLYGON":
geometry = ReadPolygonText(tokenizer, factory);
break;
case "MULTIPOLYGON":
geometry = ReadMultiPolygonText(tokenizer, factory);
break;
case "GEOMETRYCOLLECTION":
geometry = ReadGeometryCollectionText(tokenizer, factory);
break;
default:
throw new Exception(String.Format(Map.NumberFormatEnUs, "Geometrytype '{0}' is not supported.",
type));
}
return(geometry);
}
/// <summary>
/// Creates a <see cref="IMultiLineString"/> using the next token in the stream.
/// </summary>
/// <param name="tokenizer">tokenizer over a stream of text in Well-known Text format. The next tokens must form a MultiLineString Text</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>a <see cref="MultiLineString"/> specified by the next token in the stream</returns>
private static IMultiLineString ReadMultiLineStringText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
string nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(factory.CreateMultiLineString(null));
}
var lineStrings = new List <ILineString>();
lineStrings.Add(ReadLineStringText(tokenizer, factory));
nextToken = GetNextCloserOrComma(tokenizer);
while (nextToken == ",")
{
lineStrings.Add(ReadLineStringText(tokenizer, factory));
nextToken = GetNextCloserOrComma(tokenizer);
}
return(factory.CreateMultiLineString(lineStrings.ToArray()));
}
/// <summary>
/// Creates a Point using the next token in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a <Point Text>.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>Returns a Point specified by the next token in
/// the stream.</returns>
/// <remarks>
/// ParseException is thrown if an unexpected token is encountered.
/// </remarks>
private static IMultiPoint ReadMultiPointText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
string nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(factory.CreateMultiPointFromCoords((Coordinate[])null));
}
var points = new List <Coordinate>();
points.Add(new Coordinate(GetNextNumber(tokenizer), GetNextNumber(tokenizer)));
nextToken = GetNextCloserOrComma(tokenizer);
while (nextToken == ",")
{
points.Add(new Coordinate(GetNextNumber(tokenizer), GetNextNumber(tokenizer)));
nextToken = GetNextCloserOrComma(tokenizer);
}
return(factory.CreateMultiPointFromCoords(points.ToArray()));
}
/// <summary>
/// Creates a Polygon using the next token in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a <Polygon Text>.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>Returns a Polygon specified by the next token
/// in the stream</returns>
/// <remarks>
/// ParseException is thrown if the coordinates used to create the Polygon
/// shell and holes do not form closed linestrings, or if an unexpected
/// token is encountered.
/// </remarks>
private static IPolygon ReadPolygonText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
string nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(factory.CreatePolygon(null, null));
}
var exteriorRing = factory.CreateLinearRing(GetCoordinates(tokenizer));
nextToken = GetNextCloserOrComma(tokenizer);
var interiorRings = new List <ILinearRing>();
while (nextToken == ",")
{
//Add holes
interiorRings.Add(factory.CreateLinearRing(GetCoordinates(tokenizer)));
nextToken = GetNextCloserOrComma(tokenizer);
}
return(factory.CreatePolygon(exteriorRing, interiorRings.ToArray()));
}
/// <summary>
/// Creates a <see cref="IMultiPolygon"/> using the next token in the stream.
/// </summary>
/// <param name="tokenizer">tokenizer over a stream of text in Well-known Text
/// format. The next tokens must form a MultiPolygon.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>a <code>MultiPolygon</code> specified by the next token in the
/// stream, or if if the coordinates used to create the <see cref="IPolygon"/>
/// shells and holes do not form closed linestrings.</returns>
private static IMultiPolygon ReadMultiPolygonText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
var polygons = new List <IPolygon>();
string nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(factory.CreateMultiPolygon(polygons.ToArray()));
}
var polygon = ReadPolygonText(tokenizer, factory);
polygons.Add(polygon);
nextToken = GetNextCloserOrComma(tokenizer);
while (nextToken == ",")
{
polygon = ReadPolygonText(tokenizer, factory);
polygons.Add(polygon);
nextToken = GetNextCloserOrComma(tokenizer);
}
return(factory.CreateMultiPolygon(polygons.ToArray()));
}
/// <summary>
/// Returns the next array of Coordinates in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text format. The
/// next element returned by the stream should be "(" (the beginning of "(x1 y1, x2 y2, ..., xn yn)" or
/// "EMPTY".</param>
/// <returns>The next array of Coordinates in the stream, or an empty array of "EMPTY" is the
/// next element returned by the stream.</returns>
private static Coordinate[] GetCoordinates(WktStreamTokenizer tokenizer)
{
var coordinates = new List <Coordinate>();
string nextToken = GetNextEmptyOrOpener(tokenizer);
if (nextToken == "EMPTY")
{
return(coordinates.ToArray());
}
var externalCoordinate = new Coordinate();
externalCoordinate.X = GetNextNumber(tokenizer);
externalCoordinate.Y = GetNextNumber(tokenizer);
coordinates.Add(externalCoordinate);
nextToken = GetNextCloserOrComma(tokenizer);
while (nextToken == ",")
{
var internalCoordinate = new Coordinate(GetNextNumber(tokenizer), GetNextNumber(tokenizer));
coordinates.Add(internalCoordinate);
nextToken = GetNextCloserOrComma(tokenizer);
}
return(coordinates.ToArray());
}
/// <summary>
/// Creates a LineString using the next token in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known Text format. The next
/// tokens must form a LineString Text.</param>
/// <param name="factory">The factory to create the result geometry</param>
/// <returns>Returns a LineString specified by the next token in the stream.</returns>
/// <remarks>
/// ParseException is thrown if an unexpected token is encountered.
/// </remarks>
private static ILineString ReadLineStringText(WktStreamTokenizer tokenizer, IGeometryFactory factory)
{
return(factory.CreateLineString(GetCoordinates(tokenizer)));
}
/// <summary>
/// Returns the next number in the stream.
/// </summary>
/// <param name="tokenizer">Tokenizer over a stream of text in Well-known text format. The next token
/// must be a number.</param>
/// <returns>Returns the next number in the stream.</returns>
/// <remarks>
/// ParseException is thrown if the next token is not a number.
/// </remarks>
private static double GetNextNumber(WktStreamTokenizer tokenizer)
{
tokenizer.NextToken();
return(tokenizer.GetNumericValue());
}
