ceph/src/arrow/csharp/src/Apache.Arrow/Arrays/ArrowArrayConcatenator.cs

   1 // Licensed to the Apache Software Foundation (ASF) under one or more
   2 // contributor license agreements. See the NOTICE file distributed with
   3 // this work for additional information regarding copyright ownership.
   4 // The ASF licenses this file to You under the Apache License, Version 2.0
   5 // (the "License"); you may not use this file except in compliance with
   6 // the License.  You may obtain a copy of the License at
   7 //
   8 //     http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15
  16 using Apache.Arrow.Memory;
  17 using System.Collections.Generic;
  18
  19 namespace Apache.Arrow
  20 {
  21     static class ArrowArrayConcatenator
  22     {
  23         internal static IArrowArray Concatenate(IReadOnlyList<IArrowArray> arrowArrayList , MemoryAllocator allocator = default)
  24         {
  25             if(arrowArrayList == null || arrowArrayList.Count == 0)
  26             {
  27                 return null;
  28             }
  29
  30             if (arrowArrayList.Count == 1)
  31             {
  32                 return arrowArrayList[0];
  33             }
  34
  35             var arrayDataList = new List<ArrayData>(arrowArrayList.Count);
  36
  37             foreach(IArrowArray array in arrowArrayList)
  38             {
  39                 arrayDataList.Add(array.Data);
  40             }
  41
  42             return ArrowArrayFactory.BuildArray(ArrayDataConcatenator.Concatenate(arrayDataList, allocator));
  43         }
  44     }
  45 }