com.vividsolutions.jts.io

Class WKTReader


  • public class WKTReader
extends Object
    Converts a geometry in Well-Known Text format to a Geometry.

    WKTReader supports extracting Geometry objects from either Readers or Strings. This allows it to function as a parser to read Geometry objects from text blocks embedded in other data formats (e.g. XML).

    A WKTReader is parameterized by a GeometryFactory, to allow it to create Geometry objects of the appropriate implementation. In particular, the GeometryFactory determines the PrecisionModel and SRID that is used.

    The WKTReader converts all input numbers to the precise internal representation.

    Notes:

    • Keywords are case-insensitive.
    • The reader supports non-standard "LINEARRING" tags.
    • The reader uses Double.parseDouble to perform the conversion of ASCII numbers to floating point. This means it supports the Java syntax for floating point literals (including scientific notation).

    Syntax

    The following syntax specification describes the version of Well-Known Text supported by JTS. (The specification uses a syntax language similar to that used in the C and Java language specifications.) 

     WKTGeometry: one of

       WKTPoint  WKTLineString  WKTLinearRing  WKTPolygon
       WKTMultiPoint  WKTMultiLineString  WKTMultiPolygon
       WKTGeometryCollection

 WKTPoint: POINT ( Coordinate )

 WKTLineString: LINESTRING CoordinateSequence

 WKTLinearRing: LINEARRING CoordinateSequence

 WKTPolygon: POLYGON CoordinateSequenceList

 WKTMultiPoint: MULTIPOINT CoordinateSingletonList

 WKTMultiLineString: MULTILINESTRING CoordinateSequenceList

 WKTMultiPolygon:
         MULTIPOLYGON ( CoordinateSequenceList { , CoordinateSequenceList } )

 WKTGeometryCollection: 
         GEOMETRYCOLLECTION ( WKTGeometry { , WKTGeometry } )

 CoordinateSingletonList:
         ( CoordinateSingleton { , CoordinateSingleton } )
         | EMPTY
         
 CoordinateSingleton:
         ( Coordinate )
         | EMPTY

 CoordinateSequenceList:
         ( CoordinateSequence { , CoordinateSequence } )
         | EMPTY

 CoordinateSequence:
         ( Coordinate { , Coordinate } )
         | EMPTY

 Coordinate: Number Number Numberopt

 Number: A Java-style floating-point number (including NaN, with arbitrary case)
    See Also:
    WKTWriter

    • Constructor Detail

      • WKTReader

        public WKTReader()
        Creates a reader that creates objects using the default GeometryFactory.

      • WKTReader

        public WKTReader(GeometryFactory geometryFactory)
        Creates a reader that creates objects using the given GeometryFactory.
        Parameters:
        geometryFactory - the factory used to create Geometrys.

    • Method Detail

      • read

        public Geometry read(String wellKnownText)
              throws ParseException
        Reads a Well-Known Text representation of a Geometry from a String.
        Parameters:
        wellKnownText - one or more strings (see the OpenGIS Simple Features Specification) separated by whitespace
        Returns:
        a Geometry specified by wellKnownText
        Throws:
        ParseException - if a parsing problem occurs

      • read

        public Geometry read(Reader reader)
              throws ParseException
        Reads a Well-Known Text representation of a Geometry from a Reader.
        Parameters:
        reader - a Reader which will return a string (see the OpenGIS Simple Features Specification)
        Returns:
        a Geometry read from reader
        Throws:
        ParseException - if a parsing problem occurs