RobustLineIntersector defensive copyWithZ check to avoid exception with CoordinateXY or CoordinateXYM

modules/core/src/main/java/org/locationtech/jts/algorithm/RobustLineIntersector.java

@@ -15,6 +15,10 @@
  *@version 1.7
  */
 import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.CoordinateXY;
+import org.locationtech.jts.geom.CoordinateXYM;
+import org.locationtech.jts.geom.CoordinateXYZM;
+import org.locationtech.jts.geom.Coordinates;
 import org.locationtech.jts.geom.Envelope;
 
 /**
@@ -211,8 +215,8 @@ private static Coordinate copyWithZInterpolate(Coordinate p, Coordinate p1, Coor
 
   private static Coordinate copyWithZ(Coordinate p, double z) {
     Coordinate pCopy = copy(p);
-    if (! Double.isNaN(z)) {
-      pCopy.setZ( z );
+    if (! Double.isNaN(z) && Coordinates.hasZ(pCopy)) {
+      pCopy.setZ(z);
     }
     return pCopy;
   }

modules/core/src/main/java/org/locationtech/jts/geom/Coordinates.java

@@ -67,6 +67,26 @@ public static int dimension(Coordinate coordinate)
     return 3;
   }
 
+  /**
+   * Check if coordinate can store Z valye, based on subclass of {@link Coordinate}.
+   *
+   * @param coordinate supplied coordinate
+   * @return true if setZ is available
+   */
+  public static boolean hasZ(Coordinate coordinate)
+  {
+    if (coordinate instanceof CoordinateXY) {
+      return false;
+    } else if (coordinate instanceof CoordinateXYM) {
+      return false;
+    } else if (coordinate instanceof CoordinateXYZM) {
+      return true;
+    } else if (coordinate instanceof Coordinate) {
+      return true;
+    }
+    return true;
+  }
+
   /**
    * Determine number of measures based on subclass of {@link Coordinate}.
    * 

modules/core/src/test/java/org/locationtech/jts/algorithm/IntersectionTest.java

@@ -4,6 +4,14 @@
 
 import junit.framework.TestCase;
 import junit.textui.TestRunner;
+import org.locationtech.jts.geom.CoordinateSequence;
+import org.locationtech.jts.geom.CoordinateSequenceFactory;
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.geom.GeometryFactory;
+import org.locationtech.jts.geom.LinearRing;
+import org.locationtech.jts.geom.Polygon;
+import org.locationtech.jts.geom.impl.CoordinateArraySequenceFactory;
+import org.locationtech.jts.io.WKTReader;
 
 public class IntersectionTest extends TestCase {
   private static final double MAX_ABS_ERROR = 1e-5;
@@ -71,6 +79,41 @@ public void testLineSegNone() {
     checkIntersectionLineSegmentNull( 0, 0, 0, 1,    2, 9,  1, 9 );
   }
 
+  public void testIntersectionXY() throws Exception {
+    // intersection with dim 3 x dim3
+    WKTReader reader = new WKTReader();
+    Geometry poly1 = reader.read("POLYGON((0 0 0, 0 10000 2, 10000 10000 2, 10000 0 0, 0 0 0))");
+    Geometry clipArea = reader.read("POLYGON((0 0, 0 2500, 2500 2500, 2500 0, 0 0))");
+    Geometry clipped1 = poly1.intersection(clipArea);
+
+    // intersection with dim 3 x dim 2
+    GeometryFactory gf = poly1.getFactory();
+    CoordinateSequenceFactory csf = gf.getCoordinateSequenceFactory();
+    double xmin = 0.0;
+    double xmax = 2500.0;
+    double ymin = 0.0;
+    double ymax = 2500.0;
+
+    CoordinateSequence cs = csf.create(5,2);
+    cs.setOrdinate(0, 0, xmin);
+    cs.setOrdinate(0, 1, ymin);
+    cs.setOrdinate(1, 0, xmin);
+    cs.setOrdinate(1, 1, ymax);
+    cs.setOrdinate(2, 0, xmax);
+    cs.setOrdinate(2, 1, ymax);
+    cs.setOrdinate(3, 0, xmax);
+    cs.setOrdinate(3, 1, ymin);
+    cs.setOrdinate(4, 0, xmin);
+    cs.setOrdinate(4, 1, ymin);
+
+    LinearRing bounds = gf.createLinearRing(cs);
+
+    Polygon fence = gf.createPolygon(bounds, null);
+    Geometry clipped2 = poly1.intersection(fence);
+
+    assertTrue(clipped1.equals(clipped2));
+  }
+
   //==================================================
 
   private void checkIntersection(double p1x, double p1y, double p2x, double p2y,