geo/GeoShapeUtils.java

   1 package org.argeo.app.geo;
   2
   3 import java.util.ArrayList;
   4 import java.util.List;
   5 import java.util.Objects;
   6 import java.util.StringTokenizer;
   7
   8 import org.locationtech.jts.geom.Coordinate;
   9 import org.locationtech.jts.geom.Geometry;
  10 import org.locationtech.jts.geom.GeometryFactory;
  11 import org.locationtech.jts.geom.LineString;
  12 import org.locationtech.jts.geom.MultiPoint;
  13 import org.locationtech.jts.geom.Point;
  14 import org.locationtech.jts.geom.Polygon;
  15
  16 /** Utilities around ODK's GeoShape format */
  17 public class GeoShapeUtils {
  18
  19         @SuppressWarnings("unchecked")
  20         public static <T> T geoShapeToGeometry(String geoShape, Class<T> clss) {
  21                 Objects.requireNonNull(geoShape);
  22                 GeometryFactory geometryFactory = JTS.GEOMETRY_FACTORY_WGS84;
  23                 List<Coordinate> coordinates = new ArrayList<>();
  24                 StringTokenizer stSeg = new StringTokenizer(geoShape.trim(), ";");
  25                 while (stSeg.hasMoreTokens()) {
  26                         StringTokenizer stPt = new StringTokenizer(stSeg.nextToken().trim(), " ");
  27                         String lat = stPt.nextToken();
  28                         String lng = stPt.nextToken();
  29                         String alt = stPt.nextToken();
  30                         // String precision = stPt.nextToken();
  31                         Coordinate coord;
  32                         if (!alt.equals("0.0")) {
  33                                 coord = new Coordinate(Double.parseDouble(lat), Double.parseDouble(lng), Double.parseDouble(alt));
  34                         } else {
  35                                 coord = new Coordinate(Double.parseDouble(lat), Double.parseDouble(lng));
  36                         }
  37                         coordinates.add(coord);
  38                 }
  39                 if (LineString.class.isAssignableFrom(clss)) {
  40                         LineString lineString = geometryFactory
  41                                         .createLineString(coordinates.toArray(new Coordinate[coordinates.size()]));
  42                         return (T) lineString;
  43                 } else if (MultiPoint.class.isAssignableFrom(clss)) {
  44                         MultiPoint multiPoint = geometryFactory
  45                                         .createMultiPointFromCoords(coordinates.toArray(new Coordinate[coordinates.size()]));
  46                         return (T) multiPoint;
  47                 } else if (Polygon.class.isAssignableFrom(clss)) {
  48                         Coordinate first = coordinates.get(0);
  49                         Coordinate last = coordinates.get(coordinates.size() - 1);
  50                         if (!(first.getX() == last.getX() && first.getY() == last.getY())) {
  51                                 // close the line string
  52                                 coordinates.add(first);
  53                         }
  54                         Polygon polygon = geometryFactory.createPolygon(coordinates.toArray(new Coordinate[coordinates.size()]));
  55                         return (T) polygon;
  56                 } else {
  57                         throw new IllegalArgumentException("Unsupported format " + clss);
  58                 }
  59         }
  60
  61         /** Converts a {@link Geometry} with WGS84 coordinates to a GeoShape. */
  62         public static String geometryToGeoShape(Geometry geometry) {
  63                 if (geometry instanceof Point point) {
  64                         Coordinate coordinate = point.getCoordinate();
  65                         StringBuilder sb = new StringBuilder();
  66                         appendToGeoShape(sb, coordinate.getX(), coordinate.getY(), coordinate.getZ());
  67                         return sb.toString();
  68                 } else if (geometry instanceof Polygon || geometry instanceof LineString) {
  69                         StringBuilder sb = new StringBuilder();
  70                         for (Coordinate coordinate : geometry.getCoordinates()) {
  71                                 appendToGeoShape(sb, coordinate.getX(), coordinate.getY(), coordinate.getZ());
  72                                 sb.append(';');
  73                         }
  74                         return sb.toString();
  75                 } else {
  76                         throw new IllegalArgumentException("Unsupported geometry " + geometry.getClass());
  77                 }
  78         }
  79
  80         public static String geoPointToGeoShape(double lon, double lat, double alt) {
  81                 StringBuilder sb = new StringBuilder();
  82                 appendToGeoShape(sb, lon, lat, alt);
  83                 return sb.toString();
  84         }
  85
  86         private static void appendToGeoShape(StringBuilder sb, double lon, double lat, double alt) {
  87                 sb.append(lat).append(' ');
  88                 sb.append(lon).append(' ');
  89                 if (alt != Double.NaN)
  90                         sb.append(alt).append(' ');
  91                 else
  92                         sb.append("0 ");
  93                 sb.append('0');
  94         }
  95
  96         /** singleton */
  97         private GeoShapeUtils() {
  98         }
  99
 100 }