Revert "apacheGH-343: Fix ListVector offset buffer not properly serialized for nested empty arrays (apache#967)"

This reverts commit 0f8a080.

Author: lriggs

vector/src/main/java/org/apache/arrow/vector/complex/LargeListVector.java

@@ -309,14 +309,11 @@ private void setReaderAndWriterIndex() {
     offsetBuffer.readerIndex(0);
     if (valueCount == 0) {
       validityBuffer.writerIndex(0);
+      offsetBuffer.writerIndex(0);
     } else {
       validityBuffer.writerIndex(BitVectorHelper.getValidityBufferSizeFromCount(valueCount));
+      offsetBuffer.writerIndex((valueCount + 1) * OFFSET_WIDTH);
     }
-    // IPC serializer will determine readable bytes based on `readerIndex` and `writerIndex`.
-    // Both are set to 0 means 0 bytes are written to the IPC stream which will crash IPC readers
-    // in other libraries. According to Arrow spec, we should still output the offset buffer which
-    // is [0].
-    offsetBuffer.writerIndex((long) (valueCount + 1) * OFFSET_WIDTH);
   }
 
   /**

vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java

@@ -267,14 +267,11 @@ private void setReaderAndWriterIndex() {
     offsetBuffer.readerIndex(0);
     if (valueCount == 0) {
       validityBuffer.writerIndex(0);
+      offsetBuffer.writerIndex(0);
     } else {
       validityBuffer.writerIndex(BitVectorHelper.getValidityBufferSizeFromCount(valueCount));
+      offsetBuffer.writerIndex((valueCount + 1) * OFFSET_WIDTH);
     }
-    // IPC serializer will determine readable bytes based on `readerIndex` and `writerIndex`.
-    // Both are set to 0 means 0 bytes are written to the IPC stream which will crash IPC readers
-    // in other libraries. According to Arrow spec, we should still output the offset buffer which
-    // is [0].
-    offsetBuffer.writerIndex((long) (valueCount + 1) * OFFSET_WIDTH);
   }
 
   /**

vector/src/test/java/org/apache/arrow/vector/TestLargeListVector.java

@@ -1100,26 +1100,6 @@ public void testCopyValueSafeForExtensionType() throws Exception {
     }
   }
 
-  @Test
-  public void testEmptyLargeListOffsetBuffer() {
-    // Test that LargeListVector has correct readableBytes after allocation.
-    // According to Arrow spec, offset buffer must have N+1 entries.
-    // Even when N=0, it should contain [0].
-    try (LargeListVector list = LargeListVector.empty("list", allocator)) {
-      list.addOrGetVector(FieldType.nullable(MinorType.INT.getType()));
-      list.allocateNew();
-      list.setValueCount(0);
-
-      List<ArrowBuf> buffers = list.getFieldBuffers();
-      assertTrue(
-          buffers.get(1).readableBytes() >= LargeListVector.OFFSET_WIDTH,
-          "Offset buffer should have at least "
-              + LargeListVector.OFFSET_WIDTH
-              + " bytes for offset[0]");
-      assertEquals(0L, list.getOffsetBuffer().getLong(0));
-    }
-  }
-
   private void writeIntValues(UnionLargeListWriter writer, int[] values) {
     writer.startList();
     for (int v : values) {

vector/src/test/java/org/apache/arrow/vector/TestListVector.java

@@ -1379,26 +1379,6 @@ public void testCopyValueSafeForExtensionType() throws Exception {
     }
   }
 
-  @Test
-  public void testEmptyListOffsetBuffer() {
-    // Test that ListVector has correct readableBytes after allocation.
-    // According to Arrow spec, offset buffer must have N+1 entries.
-    // Even when N=0, it should contain [0].
-    try (ListVector list = ListVector.empty("list", allocator)) {
-      list.addOrGetVector(FieldType.nullable(MinorType.INT.getType()));
-      list.allocateNew();
-      list.setValueCount(0);
-
-      List<ArrowBuf> buffers = list.getFieldBuffers();
-      assertTrue(
-          buffers.get(1).readableBytes() >= BaseRepeatedValueVector.OFFSET_WIDTH,
-          "Offset buffer should have at least "
-              + BaseRepeatedValueVector.OFFSET_WIDTH
-              + " bytes for offset[0]");
-      assertEquals(0, list.getOffsetBuffer().getInt(0));
-    }
-  }
-
   private void writeIntValues(UnionListWriter writer, int[] values) {
     writer.startList();
     for (int v : values) {