5 // Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
7 // Copyright (c) 2010 Jérémie "Garuma" Laval
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:
16 // The above copyright notice and this permission notice shall be included in
17 // all copies or substantial portions of the Software.
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
29 using System.Threading;
30 using System.Collections;
31 using System.Collections.Generic;
32 using System.Collections.Concurrent;
34 namespace System.Linq.Parallel.QueryNodes
36 internal class QueryGroupByNode<TSource, TKey, TElement> : QueryStreamNode<IGrouping<TKey, TElement>, TSource>
38 Func<TSource, TKey> keySelector;
39 Func<TSource, TElement> elementSelector;
40 IEqualityComparer<TKey> comparer;
42 public QueryGroupByNode (QueryBaseNode<TSource> parent,
43 Func<TSource, TKey> keySelector,
44 Func<TSource, TElement> elementSelector,
45 IEqualityComparer<TKey> comparer)
46 : base (parent, false)
48 this.keySelector = keySelector;
49 this.elementSelector = elementSelector;
50 this.comparer = comparer;
53 internal override IEnumerable<IGrouping<TKey, TElement>> GetSequential ()
55 IEnumerable<TSource> src = Parent.GetSequential ();
57 return src.GroupBy (keySelector, elementSelector, comparer);
60 internal override IList<IEnumerable<IGrouping<TKey, TElement>>> GetEnumerables (QueryOptions options)
62 return ParallelPartitioner.CreateForChunks (GetGroupedElements ()).GetPartitions (options.PartitionCount).Wrap ();
65 internal override IList<IEnumerable<KeyValuePair<long, IGrouping<TKey, TElement>>>> GetOrderedEnumerables (QueryOptions options)
67 return ParallelPartitioner.CreateForChunks (GetGroupedElements ()).GetOrderablePartitions (options.PartitionCount).Wrap ();
70 internal IEnumerable<IGrouping<TKey, TElement>> GetGroupedElements ()
72 return (IEnumerable<System.Linq.IGrouping<TKey,TElement>>)GetStore ().Select (e => (IGrouping<TKey,TElement>)new ConcurrentGrouping<TKey, TElement> (e.Key, e.Value));
75 internal ConcurrentDictionary<TKey, ConcurrentQueue<TElement>> GetStore ()
77 var store = new ConcurrentDictionary<TKey, ConcurrentQueue<TElement>> ();
78 Func<TKey, ConcurrentQueue<TElement>> queueFactory = (_) => new ConcurrentQueue<TElement> ();
80 ParallelExecuter.ProcessAndBlock (Parent, (e, c) => {
81 ConcurrentQueue<TElement> queue = store.GetOrAdd (keySelector (e), queueFactory);
82 queue.Enqueue (elementSelector (e));