ceph/src/arrow/csharp/src/Apache.Arrow/Column.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 System;
  17 using System.Collections.Generic;
  18 using Apache.Arrow.Types;
  19
  20 namespace Apache.Arrow
  21 {
  22     /// <summary>
  23     /// A Column data structure that logically represents a column in a dataset
  24     /// </summary>
  25     public class Column
  26     {
  27         public Field Field { get;  }
  28         public ChunkedArray Data { get; }
  29
  30         public Column(Field field, IList<Array> arrays)
  31         {
  32             Data = new ChunkedArray(arrays);
  33             Field = field;
  34             if (!ValidateArrayDataTypes())
  35             {
  36                 throw new ArgumentException($"{Field.DataType} must match {Data.DataType}");
  37             }
  38         }
  39
  40         private Column(Field field, ChunkedArray arrays)
  41         {
  42             Field = field;
  43             Data = arrays;
  44         }
  45
  46         public long Length => Data.Length;
  47         public long NullCount => Data.NullCount;
  48         public string Name => Field.Name;
  49         public IArrowType Type => Field.DataType;
  50
  51         public Column Slice(int offset, int length)
  52         {
  53             return new Column(Field, Data.Slice(offset, length));
  54         }
  55
  56         public Column Slice(int offset)
  57         {
  58             return new Column(Field, Data.Slice(offset));
  59         }
  60
  61         private bool ValidateArrayDataTypes()
  62         {
  63             for (int i = 0; i < Data.ArrayCount; i++)
  64             {
  65                 if (Data.Array(i).Data.DataType != Field.DataType)
  66                 {
  67                     return false;
  68                 }
  69             }
  70             return true;
  71         }
  72     }
  73 }