From 34d9a21e014a3e0cc3a76ca9ea80355fe4411e28 Mon Sep 17 00:00:00 2001
From: Sunjeet Singh <sunjeets@netflix.com>
Date: Mon, 9 Oct 2023 07:53:54 -0700
Subject: [PATCH] Restore private modifier, cleanup, more test

---
 .../object/HollowObjectTypeDataElements.java    |  4 ++--
 .../HollowObjectTypeDataElementsJoinerTest.java | 15 +++++++++++++--
 ...llowObjectTypeDataElementsSplitJoinTest.java | 17 +++++++++++++++++
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElements.java b/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElements.java
index 09ae537b80..a28c629df4 100644
--- a/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElements.java
+++ b/hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElements.java
@@ -52,8 +52,8 @@ public class HollowObjectTypeDataElements {
     final long nullValueForField[];
     int bitsPerRecord;
 
-    int bitsPerUnfilteredField[];
-    boolean unfilteredFieldIsIncluded[];
+    private int bitsPerUnfilteredField[];
+    private boolean unfilteredFieldIsIncluded[];
 
     final ArraySegmentRecycler memoryRecycler;
     final MemoryMode memoryMode;
diff --git a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoinerTest.java b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoinerTest.java
index 81d0c8d8f3..8c4868480a 100644
--- a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoinerTest.java
+++ b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsJoinerTest.java
@@ -2,20 +2,31 @@
 
 import static org.junit.Assert.assertEquals;
 
+import com.netflix.hollow.core.write.HollowObjectTypeWriteState;
 import java.io.IOException;
 import org.junit.Assert;
 import org.junit.Test;
 
 public class HollowObjectTypeDataElementsJoinerTest extends AbstractHollowObjectTypeDataElementsSplitJoinTest {
+    @Override
+    protected void initializeTypeStates() {
+        writeStateEngine.setTargetMaxTypeShardSize(16);
+        writeStateEngine.addTypeState(new HollowObjectTypeWriteState(schema));
+    }
+
     @Test
     public void testJoin() throws IOException {
         HollowObjectTypeDataElementsJoiner joiner = new HollowObjectTypeDataElementsJoiner();
 
-        HollowObjectTypeReadState typeReadState = populateTypeStateWith(5);
+        HollowObjectTypeReadState typeReadState = populateTypeStateWith(1);
         assertEquals(1, typeReadState.numShards());
+
+        HollowObjectTypeReadState typeReadStateSharded = populateTypeStateWith(5);
         assertDataUnchanged(5);
+        assertEquals(8, typeReadStateSharded.numShards());
+
+        HollowObjectTypeDataElements joinedDataElements = joiner.join(typeReadStateSharded.currentDataElements());
 
-        HollowObjectTypeDataElements joinedDataElements = joiner.join(typeReadState.currentDataElements());
         typeReadState.setCurrentData(joinedDataElements);
         assertDataUnchanged(5);
 
diff --git a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
index d87b389ab6..3e2cf99f87 100644
--- a/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
+++ b/hollow/src/test/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeDataElementsSplitJoinTest.java
@@ -66,6 +66,23 @@ public void testSplitThenJoinWithFilter() throws IOException {
         }
     }
 
+    @Test
+    public void testSplitThenJoinWithEmptyJoin() throws IOException {
+        HollowObjectTypeDataElementsSplitter splitter = new HollowObjectTypeDataElementsSplitter();
+
+        HollowObjectTypeReadState typeReadState = populateTypeStateWith(1);
+        assertEquals(1, typeReadState.numShards());
+
+        HollowObjectTypeDataElements[] splitBy4 = splitter.split(typeReadState.currentDataElements()[0], 4);
+        assertEquals(-1, splitBy4[1].maxOrdinal);
+        assertEquals(-1, splitBy4[3].maxOrdinal);
+
+        HollowObjectTypeDataElementsJoiner joiner = new HollowObjectTypeDataElementsJoiner();
+        HollowObjectTypeDataElements joined = joiner.join(new HollowObjectTypeDataElements[]{splitBy4[1], splitBy4[3]});
+
+        assertEquals(-1, joined.maxOrdinal);
+    }
+
     // manually invoked
     // @Test
     public void testSplittingAndJoiningWithSnapshotBlob() throws Exception {