Application: gvSIG desktop

package org.gvsig.fmap.geom.operation.fromwkt;

import java.io.IOException;

import java.io.Reader;

import java.io.StreamTokenizer;

import java.io.StringReader;

import java.util.ArrayList;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.GeometryLocator;

import org.gvsig.fmap.geom.GeometryManager;

import org.gvsig.fmap.geom.Geometry.SUBTYPES;

import org.gvsig.fmap.geom.Geometry.TYPES;

import org.gvsig.fmap.geom.aggregate.MultiPoint;

import org.gvsig.fmap.geom.primitive.GeneralPathX;

import org.gvsig.fmap.geom.primitive.Point;

import org.gvsig.fmap.geom.primitive.Surface;

import com.vividsolutions.jts.geom.Coordinate;

import com.vividsolutions.jts.io.ParseException;

/**

 *  Converts a Well-Known Text string to a <code>Geometry</code>.

 * <p>

 *  The <code>WKTReader</code> allows

 *  extracting <code>Geometry</code> objects from either input streams or

 *  internal strings. This allows it to function as a parser to read <code>Geometry</code>

 *  objects from text blocks embedded in other data formats (e.g. XML). <P>

 * <p>

 * The Well-known

 *  Text format is defined in the <A HREF="http://www.opengis.org/techno/specs.htm">

 *  OpenGIS Simple Features Specification for SQL</A> . <P>

 * <p>

 *  <B>Note: </B> There is an inconsistency in the SFS. The WKT grammar states

 *  that <code>MultiPoints</code> are represented by <code>MULTIPOINT ( ( x y), (x y) )</code>

 *  , but the examples show <code>MultiPoint</code>s as <code>MULTIPOINT ( x y, x y )</code>

 *  . Other implementations follow the latter syntax, so JTS will adopt it as

 *  well.

 *

 *  A <code>WKTReader</code> is parameterized by a <code>GeometryFactory</code>

 *  , to allow it to create <code>Geometry</code> objects of the appropriate

 *  implementation. In particular, the <code>GeometryFactory</code> will

 *  determine the <code>PrecisionModel</code> and <code>SRID</code> that is

 *  used. <P>

 *

 *  The <code>WKTReader</code> will convert the input numbers to the precise

 *  internal representation.

 *

 *  Reads non-standard "LINEARRING" tags.

 *

 *@version 1.5

 */

public class WKTParser {

        private GeometryManager manager = GeometryLocator.getGeometryManager();

        /**

         * Creates a WKTReader that creates objects using a basic GeometryFactory.

         */

        public WKTParser() {

        }

        /**

         * Converts a Well-known Text representation to a <code>Geometry</code>.

         * 

         * @param wellKnownText

         *            one or more <Geometry Tagged Text>strings (see the OpenGIS

         *            Simple Features Specification) separated by whitespace

         * @return a <code>Geometry</code> specified by <code>wellKnownText</code>

         * @throws ParseException

         *             if a parsing problem occurs

         */

        public Geometry read(String wellKnownText) throws ParseException {

                StringReader reader = new StringReader(wellKnownText);

                try {

                        return read(reader);

                }

                finally {

                        reader.close();

                }

        }

        /**

         *  Converts a Well-known Text representation to a <code>Geometry</code>.

         *

         *@param  reader           a Reader which will return a <Geometry Tagged Text>

         *      string (see the OpenGIS Simple Features Specification)

         *@return                  a <code>Geometry</code> read from <code>reader</code>

         *@throws  ParseException  if a parsing problem occurs

         */

        public Geometry read(Reader reader) throws ParseException {

                StreamTokenizer tokenizer = new StreamTokenizer(reader);

                try {

                        return readGeometryTaggedText(tokenizer);

                }

                catch (IOException e) {

                        throw new ParseException(e.toString());

                } catch (InstantiationException e) {

                        throw new ParseException(e.toString());

                } catch (IllegalAccessException e) {

                        throw new ParseException(e.toString());

                }

        }

        /**

         *  Returns the next array of <code>Coordinate</code>s in the stream.

         *

         *@param  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".

         *@return                  the next array of <code>Coordinate</code>s in the

         *      stream, or an empty array if "EMPTY" is the next element returned by

         *      the stream.

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         */

        private Coordinate[] getCoordinates(StreamTokenizer tokenizer)

        throws IOException, ParseException

        {

                String nextToken = getNextEmptyOrOpener(tokenizer);

                if (nextToken.equals("EMPTY")) {

                        return new Coordinate[]{};

                }

                ArrayList coordinates = new ArrayList();

                coordinates.add(getPreciseCoordinate(tokenizer));

                nextToken = getNextCloserOrComma(tokenizer);

                while (nextToken.equals(",")) {

                        coordinates.add(getPreciseCoordinate(tokenizer));

                        nextToken = getNextCloserOrComma(tokenizer);

                }

                Coordinate[] array = new Coordinate[coordinates.size()];

                return (Coordinate[]) coordinates.toArray(array);

        }

        private Coordinate getPreciseCoordinate(StreamTokenizer tokenizer)

        throws IOException, ParseException

        {

                Coordinate coord = new Coordinate();

                coord.x = getNextNumber(tokenizer);

                coord.y = getNextNumber(tokenizer);

                if (isNumberNext(tokenizer)) {

                        coord.z = getNextNumber(tokenizer);

                }

                return coord;

        }

        private boolean isNumberNext(StreamTokenizer tokenizer) throws IOException {

                try {

                        return tokenizer.nextToken() == StreamTokenizer.TT_NUMBER;

                }

                finally {

                        tokenizer.pushBack();

                }

        }

        /**

         *  Returns the next number in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next token must be a number.

         *@return                  the next number in the stream

         *@throws  ParseException  if the next token is not a number

         *@throws  IOException     if an I/O error occurs

         */

        private double getNextNumber(StreamTokenizer tokenizer) throws IOException,

        ParseException {

                int type = tokenizer.nextToken();

                switch (type) {

                case StreamTokenizer.TT_EOF:

                        throw new ParseException("Expected number but encountered end of stream");

                case StreamTokenizer.TT_EOL:

                        throw new ParseException("Expected number but encountered end of line");

                case StreamTokenizer.TT_NUMBER:

                        return tokenizer.nval;

                case StreamTokenizer.TT_WORD:

                        throw new ParseException("Expected number but encountered word: " +

                                        tokenizer.sval);

                case '(':

                        throw new ParseException("Expected number but encountered '('");

                case ')':

                        throw new ParseException("Expected number but encountered ')'");

                case ',':

                        throw new ParseException("Expected number but encountered ','");

                }

                return 0;

        }

        /**

         *  Returns the next "EMPTY" or "(" in the stream as uppercase text.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next token must be "EMPTY" or "(".

         *@return                  the next "EMPTY" or "(" in the stream as uppercase

         *      text.

         *@throws  ParseException  if the next token is not "EMPTY" or "("

         *@throws  IOException     if an I/O error occurs

         */

        private String getNextEmptyOrOpener(StreamTokenizer tokenizer) throws IOException, ParseException {

                String nextWord = getNextWord(tokenizer);

                if (nextWord.equals("EMPTY") || nextWord.equals("(")) {

                        return nextWord;

                }

                throw new ParseException("Expected 'EMPTY' or '(' but encountered '" +

                                nextWord + "'");

        }

        /**

         *  Returns the next ")" or "," in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next token must be ")" or ",".

         *@return                  the next ")" or "," in the stream

         *@throws  ParseException  if the next token is not ")" or ","

         *@throws  IOException     if an I/O error occurs

         */

        private String getNextCloserOrComma(StreamTokenizer tokenizer) throws IOException, ParseException {

                String nextWord = getNextWord(tokenizer);

                if (nextWord.equals(",") || nextWord.equals(")")) {

                        return nextWord;

                }

                throw new ParseException("Expected ')' or ',' but encountered '" + nextWord

                                + "'");

        }

        /**

         *  Returns the next ")" in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next token must be ")".

         *@return                  the next ")" in the stream

         *@throws  ParseException  if the next token is not ")"

         *@throws  IOException     if an I/O error occurs

         */

        private String getNextCloser(StreamTokenizer tokenizer) throws IOException, ParseException {

                String nextWord = getNextWord(tokenizer);

                if (nextWord.equals(")")) {

                        return nextWord;

                }

                throw new ParseException("Expected ')' but encountered '" + nextWord + "'");

        }

        /**

         *  Returns the next word in the stream as uppercase text.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next token must be a word.

         *@return                  the next word in the stream as uppercase text

         *@throws  ParseException  if the next token is not a word

         *@throws  IOException     if an I/O error occurs

         */

        private String getNextWord(StreamTokenizer tokenizer) throws IOException, ParseException {

                int type = tokenizer.nextToken();

                switch (type) {

                case StreamTokenizer.TT_EOF:

                        throw new ParseException("Expected word but encountered end of stream");

                case StreamTokenizer.TT_EOL:

                        throw new ParseException("Expected word but encountered end of line");

                case StreamTokenizer.TT_NUMBER:

                        throw new ParseException("Expected word but encountered number: " +

                                        tokenizer.nval);

                case StreamTokenizer.TT_WORD:

                        return tokenizer.sval.toUpperCase();

                case '(':

                        return "(";

                case ')':

                        return ")";

                case ',':

                        return ",";

                }

                // Assert.shouldNeverReachHere("Encountered unexpected StreamTokenizer type: " + type);

                return null;

        }

        /**

         *  Creates a <code>Geometry</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <Geometry Tagged Text>.

         *@return                  a <code>Geometry</code> specified by the next token

         *      in the stream

         *@throws  ParseException  if the coordinates used to create a <code>Polygon</code>

         *      shell and holes do not form closed linestrings, or if an unexpected

         *      token was encountered

         *@throws  IOException     if an I/O error occurs

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readGeometryTaggedText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                String type = getNextWord(tokenizer);

                if (type.equals("POINT")) {

                        return readPointText(tokenizer);

                }

                else if (type.equals("LINESTRING")) {

                        return readLineStringText(tokenizer);

                }

                else if (type.equals("LINEARRING")) {

                        return readLinearRingText(tokenizer);

                }

                else if (type.equals("POLYGON")) {

                        return readPolygonText(tokenizer);

                }

                else if (type.equals("MULTIPOINT")) {

                        return readMultiPointText(tokenizer);

                }

                else if (type.equals("MULTILINESTRING")) {

                        return readMultiLineStringText(tokenizer);

                }

                else if (type.equals("MULTIPOLYGON")) {

                        return readMultiPolygonText(tokenizer);

                }

                /* else if (type.equals("GEOMETRYCOLLECTION")) {

      return readGeometryCollectionText(tokenizer);

    } */

                System.err.println("Unknown type: " + type);

                throw new ParseException("Unknown type: " + type);

        }

        /**

         *  Creates a <code>Point</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <Point Text>.

         *@return                  a <code>Point</code> specified by the next token in

         *      the stream

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readPointText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                String nextToken = getNextEmptyOrOpener(tokenizer);

                if (nextToken.equals("EMPTY")) {

                        return null;

                }

                Coordinate c = getPreciseCoordinate(tokenizer);

                Point point = (Point)manager.create(TYPES.POINT, SUBTYPES.GEOM2D);

                point.setX(c.x);

                point.setY(c.y);

                getNextCloser(tokenizer);

                return point;

        }

        /**

         *  Creates a <code>LineString</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <LineString Text>.

         *@return                  a <code>LineString</code> specified by the next

         *      token in the stream

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readLineStringText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                Coordinate[] arrayC = getCoordinates(tokenizer);

                GeneralPathX gp = new GeneralPathX();

                gp.moveTo(arrayC[0].x,arrayC[0].y);

                for (int i=1;i < arrayC.length; i++)

                {

                        gp.lineTo(arrayC[i].x, arrayC[i].y);

                }

                Surface surface = (Surface)manager.create(TYPES.SURFACE, SUBTYPES.GEOM2D);

                surface.setGeneralPath(gp);

                return surface;

        }

        /**

         *  Creates a <code>LinearRing</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <LineString Text>.

         *@return                  a <code>LinearRing</code> specified by the next

         *      token in the stream

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if the coordinates used to create the <code>LinearRing</code>

         *      do not form a closed linestring, or if an unexpected token was

         *      encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readLinearRingText(StreamTokenizer tokenizer)

        throws IOException, ParseException, InstantiationException, IllegalAccessException

        {

                Coordinate[] arrayC = getCoordinates(tokenizer);

                GeneralPathX gp = new GeneralPathX();

                gp.moveTo(arrayC[0].x, arrayC[0].y);

                for (int i=1;i < arrayC.length; i++)

                {

                        gp.lineTo(arrayC[i].x, arrayC[i].y);

                }

                Surface surface = (Surface)manager.create(TYPES.SURFACE, SUBTYPES.GEOM2D);

                surface.setGeneralPath(gp);

                return surface;

        }

        /**

         *  Creates a <code>MultiPoint</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <MultiPoint Text>.

         *@return                  a <code>MultiPoint</code> specified by the next

         *      token in the stream

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readMultiPointText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                Coordinate[] coords = getCoordinates(tokenizer);

                MultiPoint multiPoint = (MultiPoint)manager.create(TYPES.MULTIPOINT, SUBTYPES.GEOM2D);

                for (int i=0; i < coords.length; i++)

                {

                        Point point = (Point)manager.create(TYPES.POINT, SUBTYPES.GEOM2D);

                        point.setX(coords[i].x);

                        point.setY(coords[i].y);

                        multiPoint.addPoint(point);

                }   

                return multiPoint;

        }

        /**

         *  Creates a <code>Polygon</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <Polygon Text>.

         *@return                  a <code>Polygon</code> specified by the next token

         *      in the stream

         *@throws  ParseException  if the coordinates used to create the <code>Polygon</code>

         *      shell and holes do not form closed linestrings, or if an unexpected

         *      token was encountered.

         *@throws  IOException     if an I/O error occurs

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readPolygonText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                String nextToken = getNextEmptyOrOpener(tokenizer);

                if (nextToken.equals("EMPTY")) {

                        return null;

                }

                ArrayList holes = new ArrayList();

                Geometry shell = readLinearRingText(tokenizer);

                nextToken = getNextCloserOrComma(tokenizer);

                while (nextToken.equals(",")) {

                        Geometry hole = readLinearRingText(tokenizer);

                        holes.add(hole);

                        nextToken = getNextCloserOrComma(tokenizer);

                }

                // LinearRing[] array = new LinearRing[holes.size()];

                return shell; //geometryFactory.createPolygon(shell, (LinearRing[]) holes.toArray(array));

        }

        /**

         *  Creates a <code>MultiLineString</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <MultiLineString Text>.

         *@return                  a <code>MultiLineString</code> specified by the

         *      next token in the stream

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        private Geometry readMultiLineStringText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                // TODO: HACER ESTO BIEN, CON UN GENERAL PATH

                String nextToken = getNextEmptyOrOpener(tokenizer);

                if (nextToken.equals("EMPTY")) {

                        return null;

                }

                ArrayList lineStrings = new ArrayList();

                Geometry lineString = readLineStringText(tokenizer);

                lineStrings.add(lineString);

                nextToken = getNextCloserOrComma(tokenizer);

                while (nextToken.equals(",")) {

                        lineString = readLineStringText(tokenizer);

                        lineStrings.add(lineString);

                        nextToken = getNextCloserOrComma(tokenizer);

                } 

                // LineString[] array = new LineString[lineStrings.size()];

                return lineString; // geometryFactory.createMultiLineString((LineString[]) lineStrings.toArray(array));

        }

        /**

         *  Creates a <code>MultiPolygon</code> using the next token in the stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <MultiPolygon Text>.

         *@return                  a <code>MultiPolygon</code> specified by the next

         *      token in the stream, or if if the coordinates used to create the

         *      <code>Polygon</code> shells and holes do not form closed linestrings.

         *@throws  IOException     if an I/O error occurs

         *@throws  ParseException  if an unexpected token was encountered

         * @throws IllegalAccessException 

         * @throws InstantiationException 

         */

        // TODO:

        private Geometry readMultiPolygonText(StreamTokenizer tokenizer) throws IOException, ParseException, InstantiationException, IllegalAccessException {

                String nextToken = getNextEmptyOrOpener(tokenizer);

                if (nextToken.equals("EMPTY")) {

                        return null;

                }

                ArrayList polygons = new ArrayList();

                Geometry polygon = readPolygonText(tokenizer);

                /* polygons.add(polygon);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      polygon = readPolygonText(tokenizer);

      polygons.add(polygon);

      nextToken = getNextCloserOrComma(tokenizer);

    } */

                // Polygon[] array = new Polygon[polygons.size()];

                return polygon; //geometryFactory.createMultiPolygon((Polygon[]) polygons.toArray(array));

        } 

        /**

         *  Creates a <code>GeometryCollection</code> using the next token in the

         *  stream.

         *

         *@param  tokenizer        tokenizer over a stream of text in Well-known Text

         *      format. The next tokens must form a <GeometryCollection Text>.

         *@return                  a <code>GeometryCollection</code> specified by the

         *      next token in the stream

         *@throws  ParseException  if the coordinates used to create a <code>Polygon</code>

         *      shell and holes do not form closed linestrings, or if an unexpected

         *      token was encountered

         *@throws  IOException     if an I/O error occurs

         */

        // TODO:

        /* private GeometryCollection readGeometryCollectionText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return geometryFactory.createGeometryCollection(new Geometry[]{});

    }

    ArrayList geometries = new ArrayList();

    Geometry geometry = readGeometryTaggedText(tokenizer);

    geometries.add(geometry);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      geometry = readGeometryTaggedText(tokenizer);

      geometries.add(geometry);

      nextToken = getNextCloserOrComma(tokenizer);

    }

    Geometry[] array = new Geometry[geometries.size()];

    return geometryFactory.createGeometryCollection((Geometry[]) geometries.toArray(array));

  } */

}