vector/src/main/java/org/apache/arrow/vector/complex/LargeListVector.java [232:329]:
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    final double totalListSize = endOffset - startOffset;
    return totalListSize / valueCount;
  }

  @Override
  public List<FieldVector> getChildrenFromFields() {
    return singletonList(getDataVector());
  }

  /**
   * Load the buffers of this vector with provided source buffers. The caller manages the source
   * buffers and populates them before invoking this method.
   *
   * @param fieldNode the fieldNode indicating the value count
   * @param ownBuffers the buffers for this Field (own buffers only, children not included)
   */
  @Override
  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
    if (ownBuffers.size() != 2) {
      throw new IllegalArgumentException(
          "Illegal buffer count, expected " + 2 + ", got: " + ownBuffers.size());
    }

    ArrowBuf bitBuffer = ownBuffers.get(0);
    ArrowBuf offBuffer = ownBuffers.get(1);

    validityBuffer.getReferenceManager().release();
    validityBuffer = BitVectorHelper.loadValidityBuffer(fieldNode, bitBuffer, allocator);
    offsetBuffer.getReferenceManager().release();
    offsetBuffer = offBuffer.getReferenceManager().retain(offBuffer, allocator);

    validityAllocationSizeInBytes = checkedCastToInt(validityBuffer.capacity());
    offsetAllocationSizeInBytes = offsetBuffer.capacity();

    lastSet = fieldNode.getLength() - 1;
    valueCount = fieldNode.getLength();
  }

  /**
   * Get the buffers belonging to this vector.
   *
   * @return the inner buffers.
   */
  @Override
  public List<ArrowBuf> getFieldBuffers() {
    List<ArrowBuf> result = new ArrayList<>(2);
    setReaderAndWriterIndex();
    result.add(validityBuffer);
    result.add(offsetBuffer);

    return result;
  }

  /**
   * Export the buffers of the fields for C Data Interface. This method traverse the buffers and
   * export buffer and buffer's memory address into a list of buffers and a pointer to the list of
   * buffers.
   */
  @Override
  public void exportCDataBuffers(List<ArrowBuf> buffers, ArrowBuf buffersPtr, long nullValue) {
    exportBuffer(validityBuffer, buffers, buffersPtr, nullValue, true);

    if (offsetBuffer.capacity() == 0) {
      // Empty offset buffer is allowed for historical reason.
      // To export it through C Data interface, we need to allocate a buffer with one offset.
      // We set `retain = false` to explicitly not increase the ref count for the exported buffer.
      // The ref count of the newly created buffer (i.e., 1) already represents the usage
      // at imported side.
      exportBuffer(allocateOffsetBuffer(OFFSET_WIDTH), buffers, buffersPtr, nullValue, false);
    } else {
      exportBuffer(offsetBuffer, buffers, buffersPtr, nullValue, true);
    }
  }

  /** Set the reader and writer indexes for the inner buffers. */
  private void setReaderAndWriterIndex() {
    validityBuffer.readerIndex(0);
    offsetBuffer.readerIndex(0);
    if (valueCount == 0) {
      validityBuffer.writerIndex(0);
      offsetBuffer.writerIndex(0);
    } else {
      validityBuffer.writerIndex(getValidityBufferSizeFromCount(valueCount));
      offsetBuffer.writerIndex((valueCount + 1) * OFFSET_WIDTH);
    }
  }

  /**
   * Get the inner vectors.
   *
   * @return the inner vectors for this field as defined by the TypeLayout
   * @deprecated This API will be removed as the current implementations no longer support inner
   *     vectors.
   */
  @Deprecated
  @Override
  public List<BufferBacked> getFieldInnerVectors() {
    throw new UnsupportedOperationException("There are no inner vectors. Use getFieldBuffers");
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vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java [190:287]:
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    final double totalListSize = endOffset - startOffset;
    return totalListSize / valueCount;
  }

  @Override
  public List<FieldVector> getChildrenFromFields() {
    return singletonList(getDataVector());
  }

  /**
   * Load the buffers of this vector with provided source buffers. The caller manages the source
   * buffers and populates them before invoking this method.
   *
   * @param fieldNode the fieldNode indicating the value count
   * @param ownBuffers the buffers for this Field (own buffers only, children not included)
   */
  @Override
  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
    if (ownBuffers.size() != 2) {
      throw new IllegalArgumentException(
          "Illegal buffer count, expected " + 2 + ", got: " + ownBuffers.size());
    }

    ArrowBuf bitBuffer = ownBuffers.get(0);
    ArrowBuf offBuffer = ownBuffers.get(1);

    validityBuffer.getReferenceManager().release();
    validityBuffer = BitVectorHelper.loadValidityBuffer(fieldNode, bitBuffer, allocator);
    offsetBuffer.getReferenceManager().release();
    offsetBuffer = offBuffer.getReferenceManager().retain(offBuffer, allocator);

    validityAllocationSizeInBytes = checkedCastToInt(validityBuffer.capacity());
    offsetAllocationSizeInBytes = offsetBuffer.capacity();

    lastSet = fieldNode.getLength() - 1;
    valueCount = fieldNode.getLength();
  }

  /**
   * Get the buffers belonging to this vector.
   *
   * @return the inner buffers.
   */
  @Override
  public List<ArrowBuf> getFieldBuffers() {
    List<ArrowBuf> result = new ArrayList<>(2);
    setReaderAndWriterIndex();
    result.add(validityBuffer);
    result.add(offsetBuffer);

    return result;
  }

  /**
   * Export the buffers of the fields for C Data Interface. This method traverse the buffers and
   * export buffer and buffer's memory address into a list of buffers and a pointer to the list of
   * buffers.
   */
  @Override
  public void exportCDataBuffers(List<ArrowBuf> buffers, ArrowBuf buffersPtr, long nullValue) {
    exportBuffer(validityBuffer, buffers, buffersPtr, nullValue, true);

    if (offsetBuffer.capacity() == 0) {
      // Empty offset buffer is allowed for historical reason.
      // To export it through C Data interface, we need to allocate a buffer with one offset.
      // We set `retain = false` to explicitly not increase the ref count for the exported buffer.
      // The ref count of the newly created buffer (i.e., 1) already represents the usage
      // at imported side.
      exportBuffer(allocateOffsetBuffer(OFFSET_WIDTH), buffers, buffersPtr, nullValue, false);
    } else {
      exportBuffer(offsetBuffer, buffers, buffersPtr, nullValue, true);
    }
  }

  /** Set the reader and writer indexes for the inner buffers. */
  private void setReaderAndWriterIndex() {
    validityBuffer.readerIndex(0);
    offsetBuffer.readerIndex(0);
    if (valueCount == 0) {
      validityBuffer.writerIndex(0);
      offsetBuffer.writerIndex(0);
    } else {
      validityBuffer.writerIndex(getValidityBufferSizeFromCount(valueCount));
      offsetBuffer.writerIndex((valueCount + 1) * OFFSET_WIDTH);
    }
  }

  /**
   * Get the inner vectors.
   *
   * @return the inner vectors for this field as defined by the TypeLayout
   * @deprecated This API will be removed as the current implementations no longer support inner
   *     vectors.
   */
  @Deprecated
  @Override
  public List<BufferBacked> getFieldInnerVectors() {
    throw new UnsupportedOperationException("There are no inner vectors. Use getFieldBuffers");
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