| // 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 |
| // |
| // http://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. |
| |
| using System; |
| using System.Collections.Generic; |
| using Apache.Arrow; |
| using Apache.Arrow.Types; |
| |
| namespace Apache.Arrow |
| { |
| /// <summary> |
| /// A data structure to manage a list of primitive Array arrays logically as one large array |
| /// </summary> |
| public class ChunkedArray |
| { |
| private IList<Array> Arrays { get; } |
| public IArrowType DataType { get; } |
| public long Length { get; } |
| public long NullCount { get; } |
| |
| public int ArrayCount |
| { |
| get => Arrays.Count; |
| } |
| |
| public Array Array(int index) => Arrays[index]; |
| |
| public ChunkedArray(IList<Array> arrays) |
| { |
| Arrays = arrays ?? throw new ArgumentNullException(nameof(arrays)); |
| if (arrays.Count < 1) |
| { |
| throw new ArgumentException($"Count must be at least 1. Got {arrays.Count} instead"); |
| } |
| DataType = arrays[0].Data.DataType; |
| foreach (Array array in arrays) |
| { |
| Length += array.Length; |
| NullCount += array.NullCount; |
| } |
| } |
| |
| public ChunkedArray(Array array) : this(new[] { array }) { } |
| |
| public ChunkedArray Slice(long offset, long length) |
| { |
| if (offset >= Length) |
| { |
| throw new ArgumentException($"Index {offset} cannot be greater than the Column's Length {Length}"); |
| } |
| |
| int curArrayIndex = 0; |
| int numArrays = Arrays.Count; |
| while (curArrayIndex < numArrays && offset > Arrays[curArrayIndex].Length) |
| { |
| offset -= Arrays[curArrayIndex].Length; |
| curArrayIndex++; |
| } |
| |
| IList<Array> newArrays = new List<Array>(); |
| while (curArrayIndex < numArrays && length > 0) |
| { |
| newArrays.Add(Arrays[curArrayIndex].Slice((int)offset, |
| length > Arrays[curArrayIndex].Length ? Arrays[curArrayIndex].Length : (int)length)); |
| length -= Arrays[curArrayIndex].Length - offset; |
| offset = 0; |
| curArrayIndex++; |
| } |
| return new ChunkedArray(newArrays); |
| } |
| |
| public ChunkedArray Slice(long offset) |
| { |
| return Slice(offset, Length - offset); |
| } |
| |
| // TODO: Flatten for Structs |
| } |
| } |