Deep copy segment when duplicate cube instance

(cherry picked from commit 4d5cf906fbe4cd840e2daf7333be8c52c7ccfb29)

core-cube/src/main/java/org/apache/kylin/cube/CubeInstance.java

@@ -191,6 +191,9 @@ public CubeSegment getOriginalSegmentToOptimize(CubeSegment optimizedSegment) {
     }
 
     public CubeDesc getDescriptor() {
+        if (config == null) {
+            return null;
+        }
         return CubeDescManager.getInstance(config).getCubeDesc(descName);
     }
 
@@ -297,6 +300,10 @@ public void setDisplayName(String displayName) {
 
     @Override
     public int getCost() {
+        if (getDescriptor() == null) {
+            //in case not initialized
+            return 0;
+        }
         int countedDimensionNum = getRowKeyColumnCount();
         int c = countedDimensionNum * COST_WEIGHT_DIMENSION + getMeasures().size() * COST_WEIGHT_MEASURE;
         DataModelDesc model = getModel();
@@ -348,7 +355,7 @@ public CubeSegment getSegment(String name, SegmentStatusEnum status) {
     }
 
     public void setSegments(Segments segments) {
-        this.segments = segments;
+        this.segments = new Segments<>(segments);
     }
 
     public CubeSegment getSegmentById(String segmentId) {

core-cube/src/test/java/org/apache/kylin/cube/CubeInstanceTest.java

@@ -18,17 +18,18 @@
 
 package org.apache.kylin.cube;
 
-import static org.junit.Assert.assertNotNull;
-
 import java.io.DataInputStream;
 import java.io.FileInputStream;
 import java.io.InputStream;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.UUID;
 
 import org.apache.kylin.common.persistence.JsonSerializer;
 import org.apache.kylin.cube.cuboid.TreeCuboidScheduler;
+import org.apache.kylin.metadata.model.SegmentStatusEnum;
+import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -56,6 +57,21 @@ public void getTreeCuboidSchedulerTest() {
         for (Long cuboid : cuboids) {
             System.out.println(cuboid + ":" + cuboidsWithRowCnt.get(cuboid));
         }
-        assertNotNull(cuboidsWithRowCnt.get(255L));
+        Assert.assertNotNull(cuboidsWithRowCnt.get(255L));
+    }
+
+    @Test
+    public void copyCubeSegmentTest() {
+        int origSegCount = cubeInstance.getSegments().size();
+        CubeInstance newCubeInstance = CubeInstance.getCopyOf(cubeInstance);
+
+        CubeSegment mockSeg = new CubeSegment();
+        mockSeg.setUuid(UUID.randomUUID().toString());
+        mockSeg.setStorageLocationIdentifier(UUID.randomUUID().toString());
+        mockSeg.setStatus(SegmentStatusEnum.READY);
+        newCubeInstance.getSegments().add(mockSeg);
+
+        Assert.assertEquals(origSegCount, cubeInstance.getSegments().size());
+        Assert.assertEquals(origSegCount + 1, newCubeInstance.getSegments().size());
     }
 }