mcs/class/System.Core/System.Linq.Parallel.QueryNodes/QueryZipNode.cs

   1 //
   2 // QueryZipNode.cs
   3 //
   4 // Author:
   5 //       Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
   6 //
   7 // Copyright (c) 2010 Jérémie "Garuma" Laval
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining a copy
  10 // of this software and associated documentation files (the "Software"), to deal
  11 // in the Software without restriction, including without limitation the rights
  12 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13 // copies of the Software, and to permit persons to whom the Software is
  14 // furnished to do so, subject to the following conditions:
  15 //
  16 // The above copyright notice and this permission notice shall be included in
  17 // all copies or substantial portions of the Software.
  18 //
  19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  25 // THE SOFTWARE.
  26
  27 #if NET_4_0
  28 using System;
  29 using System.Threading;
  30 using System.Linq;
  31 using System.Collections.Generic;
  32 using System.Collections.Concurrent;
  33
  34 namespace System.Linq.Parallel.QueryNodes
  35 {
  36         internal class QueryZipNode<TFirst, TSecond, TResult> : QueryMuxNode<TFirst, TSecond, TResult>
  37         {
  38                 Func<TFirst, TSecond, TResult> resultSelector;
  39
  40                 public QueryZipNode (Func<TFirst, TSecond, TResult> resultSelector, QueryBaseNode<TFirst> first, QueryBaseNode<TSecond> second)
  41                         : base (first, second)
  42                 {
  43                         this.resultSelector = resultSelector;
  44                 }
  45
  46                 internal override IEnumerable<TResult> GetSequential ()
  47                 {
  48                         IEnumerable<TFirst> first = Parent.GetSequential ();
  49                         IEnumerable<TSecond> second = Second.GetSequential ();
  50
  51                         return first.Zip (second, resultSelector);
  52                 }
  53
  54                 internal override IList<IEnumerable<TResult>> GetEnumerables (QueryOptions options)
  55                 {
  56                         var first = Parent.GetEnumerables (options);
  57                         var second = Second.GetEnumerables (options);
  58
  59                         if (first.Count != second.Count)
  60                                 throw new InvalidOperationException ("Internal size mismatch");
  61
  62                         return first
  63                                 .Select ((f, i) => GetEnumerable (f, second[i]))
  64                                 .ToList ();
  65                 }
  66
  67                 IEnumerable<TResult> GetEnumerable (IEnumerable<TFirst> first, IEnumerable<TSecond> second)
  68                 {
  69                         IEnumerator<TFirst> eFirst = first.GetEnumerator ();
  70                         IEnumerator<TSecond> eSecond = second.GetEnumerator ();
  71
  72                         try {
  73                                 while (eFirst.MoveNext ()) {
  74                                         if (!eSecond.MoveNext ())
  75                                                 yield break;
  76
  77                                         yield return resultSelector (eFirst.Current, eSecond.Current);
  78                                 }
  79                         } finally {
  80                                 eFirst.Dispose ();
  81                                 eSecond.Dispose ();
  82                         }
  83                 }
  84
  85                 internal override IList<IEnumerable<KeyValuePair<long, TResult>>> GetOrderedEnumerables (QueryOptions options)
  86                 {
  87                         var first = Parent.GetOrderedEnumerables (options);
  88                         var second = Second.GetOrderedEnumerables (options);
  89
  90                         if (first.Count != second.Count)
  91                                 throw new InvalidOperationException ("Internal size mismatch");
  92
  93                         var store1 = new KeyValuePair<long, TFirst>[first.Count];
  94                         var store2 = new KeyValuePair<long, TSecond>[second.Count];
  95
  96                         var barrier = new Barrier (first.Count, delegate {
  97                                 Array.Sort (store1, (e1, e2) => e1.Key.CompareTo (e2.Key));
  98                                 Array.Sort (store2, (e1, e2) => e1.Key.CompareTo (e2.Key));
  99                         });
 100
 101                         return first
 102                                 .Select ((f, i) => GetEnumerable (f, second[i], i , store1, store2, barrier))
 103                                 .ToList ();
 104                 }
 105
 106                 IEnumerable<KeyValuePair<long, TResult>> GetEnumerable (IEnumerable<KeyValuePair<long, TFirst>> first,
 107                                                                         IEnumerable<KeyValuePair<long, TSecond>> second,
 108                                                                         int index,
 109                                                                         KeyValuePair<long, TFirst>[] store1,
 110                                                                         KeyValuePair<long, TSecond>[] store2,
 111                                                                         Barrier barrier)
 112                 {
 113                         var eFirst = first.GetEnumerator ();
 114                         var eSecond = second.GetEnumerator ();
 115
 116                         try {
 117                                 while (eFirst.MoveNext ()) {
 118                                         if (!eSecond.MoveNext ())
 119                                                 break;
 120
 121                                         store1[index] = eFirst.Current;
 122                                         store2[index] = eSecond.Current;
 123
 124                                         barrier.SignalAndWait ();
 125
 126                                         yield return new KeyValuePair<long, TResult> (store1[index].Key,
 127                                                                                       resultSelector (store1[index].Value, store2[index].Value));
 128                                 }
 129                         } finally {
 130                                 barrier.RemoveParticipant ();
 131                                 eFirst.Dispose ();
 132                                 eSecond.Dispose ();
 133                         }
 134                 }
 135         }
 136 }
 137
 138 #endif