Preserve Z/M when converting coordinate sequences

Author: edmondchuc

jena-geosparql/src/main/java/org/apache/jena/geosparql/implementation/jts/CustomCoordinateSequenceFactory.java

@@ -48,7 +48,21 @@ public CoordinateSequence create(CoordinateSequence coordSeq) {
             CustomCoordinateSequence customCoordSeq = (CustomCoordinateSequence) coordSeq;
             copyCoordSeq = customCoordSeq.copy();
         } else {
-            copyCoordSeq = new CustomCoordinateSequence(coordSeq.toCoordinateArray());
+            CoordinateSequenceDimensions dimensions;
+            if (coordSeq.hasM()) {
+                dimensions = coordSeq.hasZ() ? CoordinateSequenceDimensions.XYZM : CoordinateSequenceDimensions.XYM;
+            } else {
+                dimensions = coordSeq.hasZ() ? CoordinateSequenceDimensions.XYZ : CoordinateSequenceDimensions.XY;
+            }
+            copyCoordSeq = new CustomCoordinateSequence(coordSeq.size(), dimensions);
+            for (int i = 0; i < coordSeq.size(); i++) {
+                copyCoordSeq.setOrdinate(i, CoordinateSequence.X, coordSeq.getX(i));
+                copyCoordSeq.setOrdinate(i, CoordinateSequence.Y, coordSeq.getY(i));
+                if (coordSeq.hasZ())
+                    copyCoordSeq.setOrdinate(i, CoordinateSequence.Z, coordSeq.getZ(i));
+                if (coordSeq.hasM())
+                    copyCoordSeq.setOrdinate(i, CoordinateSequence.M, coordSeq.getM(i));
+            }
         }
 
         return copyCoordSeq;

jena-geosparql/src/test/java/org/apache/jena/geosparql/implementation/jts/CustomCoordinateSequenceFactoryTest.java

@@ -0,0 +1,81 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ *   SPDX-License-Identifier: Apache-2.0
+ */
+package org.apache.jena.geosparql.implementation.jts;
+
+import org.junit.Test;
+import org.locationtech.jts.geom.CoordinateSequence;
+import org.locationtech.jts.geom.impl.CoordinateArraySequence;
+
+import static org.junit.Assert.*;
+
+public class CustomCoordinateSequenceFactoryTest {
+    @Test
+    public void conversionPreservesLayoutsValuesAndIndependence() {
+        for (int[] layout : new int[][] { { 2, 0 }, { 3, 0 }, { 3, 1 }, { 4, 1 } }) {
+            CoordinateSequence source = new CoordinateArraySequence(2, layout[0], layout[1]);
+            for (int i = 0; i < source.size(); i++) {
+                source.setOrdinate(i, 0, 100 + i);
+                source.setOrdinate(i, 1, 10 + i);
+                if (source.hasZ())
+                    source.setOrdinate(i, 2, i == 0 ? Double.NaN : 9);
+                if (source.hasM())
+                    source.setOrdinate(i, source.getDimension() - 1, i == 0 ? Double.NaN : 8);
+            }
+            CoordinateSequence converted = new CustomCoordinateSequenceFactory().create(source);
+            assertLayout(source, converted);
+            for (int i = 0; i < source.size(); i++) {
+                assertEquals(source.getX(i), converted.getX(i), 0);
+                assertEquals(source.getY(i), converted.getY(i), 0);
+                assertEquals(source.getZ(i), converted.getZ(i), 0);
+                assertEquals(source.getM(i), converted.getM(i), 0);
+            }
+            converted.setOrdinate(1, CoordinateSequence.X, -1);
+            converted.setOrdinate(1, CoordinateSequence.Y, -1);
+            assertEquals(101, source.getX(1), 0);
+            assertEquals(11, source.getY(1), 0);
+            if (source.hasZ()) {
+                converted.setOrdinate(1, CoordinateSequence.Z, -1);
+                assertEquals(9, source.getZ(1), 0);
+            }
+            if (source.hasM()) {
+                converted.setOrdinate(1, CoordinateSequence.M, -1);
+                assertEquals(8, source.getM(1), 0);
+            }
+        }
+    }
+
+    @Test
+    public void conversionPreservesEmptyLayouts() {
+        for (int[] layout : new int[][] { { 2, 0 }, { 3, 0 }, { 3, 1 }, { 4, 1 } }) {
+            CoordinateSequence source = new CoordinateArraySequence(0, layout[0], layout[1]);
+            assertLayout(source, new CustomCoordinateSequenceFactory().create(source));
+        }
+    }
+
+    private static void assertLayout(CoordinateSequence source, CoordinateSequence converted) {
+        assertNotSame(source, converted);
+        assertEquals(source.size(), converted.size());
+        assertEquals(source.getDimension(), converted.getDimension());
+        assertEquals(source.getMeasures(), converted.getMeasures());
+        assertEquals(source.hasZ(), converted.hasZ());
+        assertEquals(source.hasM(), converted.hasM());
+    }
+}