gis/runtime/org.argeo.gis.geotools/src/main/java/org/argeo/geotools/jcr/GeoJcrUtils.java

   1 package org.argeo.geotools.jcr;
   2
   3 import javax.jcr.Node;
   4
   5 import org.apache.commons.logging.Log;
   6 import org.apache.commons.logging.LogFactory;
   7 import org.argeo.ArgeoException;
   8 import org.argeo.jcr.gis.GisNames;
   9 import org.argeo.jcr.gis.GisTypes;
  10 import org.geotools.geometry.DirectPosition2D;
  11 import org.geotools.geometry.jts.JTS;
  12 import org.geotools.referencing.CRS;
  13 import org.opengis.geometry.DirectPosition;
  14 import org.opengis.referencing.crs.CoordinateReferenceSystem;
  15 import org.opengis.referencing.operation.MathTransform;
  16
  17 import com.vividsolutions.jts.geom.Coordinate;
  18 import com.vividsolutions.jts.geom.Geometry;
  19 import com.vividsolutions.jts.geom.GeometryFactory;
  20 import com.vividsolutions.jts.geom.Point;
  21
  22 /** Utilities to map JCR from/to JTS and GeoTools */
  23 public class GeoJcrUtils {
  24         private final static Log log = LogFactory.getLog(GeoJcrUtils.class);
  25
  26         /** Transforms a geometry node into position within its CRS */
  27         public static DirectPosition nodeToPosition(Node node) {
  28                 try {
  29                         if (node.isNodeType(GisTypes.GIS_POINT)) {
  30                                 CoordinateReferenceSystem crs = getCoordinateReferenceSystem(node);
  31                                 Point point = (Point) nodeToGeometry(node);
  32                                 return new DirectPosition2D(crs, point.getX(), point.getY());
  33                         } else {
  34                                 throw new ArgeoException(node + " is not of a supported type");
  35                         }
  36                 } catch (Exception e) {
  37                         throw new ArgeoException("Cannot extract position from " + node, e);
  38                 }
  39         }
  40
  41         /** Transforms a geometry node into a JTS geometry. */
  42         public static Geometry nodeToGeometry(Node node) {
  43                 try {
  44                         if (node.isNodeType(GisTypes.GIS_POINT)
  45                                         || node.isNodeType(GisTypes.GIS_COORDINATE)) {
  46                                 Coordinate coo;
  47                                 if (node.hasProperty(GisNames.GIS_Z))
  48                                         coo = new Coordinate(node.getProperty(GisNames.GIS_X)
  49                                                         .getDouble(), node.getProperty(GisNames.GIS_Y)
  50                                                         .getDouble(), node.getProperty(GisNames.GIS_Z)
  51                                                         .getDouble());
  52                                 else
  53                                         coo = new Coordinate(node.getProperty(GisNames.GIS_X)
  54                                                         .getDouble(), node.getProperty(GisNames.GIS_Y)
  55                                                         .getDouble());
  56
  57                                 // TODO: use factory finder
  58                                 // GeometryFactory geometryFactory =
  59                                 // JTSFactoryFinder.getGeometryFactory(null);
  60                                 GeometryFactory geometryFactory = new GeometryFactory();
  61                                 return geometryFactory.createPoint(coo);
  62                         } else {
  63                                 throw new ArgeoException(node + " is not of a supported type");
  64                         }
  65                 } catch (Exception e) {
  66                         throw new ArgeoException("Cannot map " + node + " to a geometry", e);
  67                 }
  68         }
  69
  70         /** Reads and interpret the coordinate reference system from a node. */
  71         public static CoordinateReferenceSystem getCoordinateReferenceSystem(
  72                         Node node) {
  73                 try {
  74                         if (!node.isNodeType(GisTypes.GIS_LOCATED))
  75                                 throw new ArgeoException(node + " is not of type "
  76                                                 + GisTypes.GIS_LOCATED);
  77                         // Coordinate reference system
  78                         String srs = node.getProperty(GisNames.GIS_SRS).getString();
  79                         CoordinateReferenceSystem crs;
  80                         try {
  81                                 // first, try to decode an EPSG code
  82                                 crs = CRS.decode(srs);
  83                         } catch (Exception e) {
  84                                 // if it fails, try a WKT
  85                                 try {
  86                                         crs = CRS.parseWKT(srs);
  87                                 } catch (Exception e1) {
  88                                         // if it fails as well, log the error
  89                                         log.error("Cannot parse WKT " + srs, e1);
  90                                         // and then the previous error (probably more relevant)
  91                                         throw e;
  92                                 }
  93                         }
  94                         return crs;
  95                 } catch (Exception e) {
  96                         throw new ArgeoException(
  97                                         "Cannot get coordinate reference system for " + node, e);
  98                 }
  99         }
 100
 101         public static Geometry reproject(CoordinateReferenceSystem crs,
 102                         Geometry geometry, CoordinateReferenceSystem targetCrs) {
 103                 try {
 104                         MathTransform transform = CRS.findMathTransform(crs, targetCrs);
 105                         return JTS.transform(geometry, transform);
 106                 } catch (Exception e) {
 107                         throw new ArgeoException("Cannot reproject " + geometry + " from "
 108                                         + crs + " to " + targetCrs);
 109                 }
 110         }
 111 }