3 // Copyright (c) 2011 Jérémie "garuma" Laval
4 // Copyright (c) 2012 Petr Onderka
6 // Permission is hereby granted, free of charge, to any person obtaining a copy
7 // of this software and associated documentation files (the "Software"), to deal
8 // in the Software without restriction, including without limitation the rights
9 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 // copies of the Software, and to permit persons to whom the Software is
11 // furnished to do so, subject to the following conditions:
13 // The above copyright notice and this permission notice shall be included in
14 // all copies or substantial portions of the Software.
16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 using System.Collections.Concurrent;
26 namespace System.Threading.Tasks.Dataflow {
28 /// Target block use by join blocks in their TargetN properties.
29 /// Also serves as its own <see cref="MessageBox{TInput}"/>.
31 class JoinTarget<TTarget> : MessageBox<TTarget>, ITargetBlock<TTarget> {
32 readonly IDataflowBlock joinBlock;
33 readonly Action signal;
36 IDataflowBlock joinBlock, Action signal, CompletionHelper helper,
37 Func<bool> externalCompleteTester, DataflowBlockOptions options,
38 bool greedy, Func<bool> canAccept)
39 : base (null, new BlockingCollection<TTarget> (), helper, externalCompleteTester,
40 options, greedy, canAccept)
42 this.joinBlock = joinBlock;
48 /// Makes sure the input queue is processed the way it needs to,
49 /// by signaling the parent join block.
51 protected override void EnsureProcessing (bool newItem)
57 /// The input queue of this block.
59 public BlockingCollection<TTarget> Buffer {
60 get { return MessageQueue; }
63 DataflowMessageStatus ITargetBlock<TTarget>.OfferMessage (
64 DataflowMessageHeader messageHeader, TTarget messageValue,
65 ISourceBlock<TTarget> source, bool consumeToAccept)
67 return OfferMessage (messageHeader, messageValue, source, consumeToAccept);
70 void IDataflowBlock.Complete ()
75 Task IDataflowBlock.Completion {
76 get { throw new NotSupportedException (); }
79 void IDataflowBlock.Fault (Exception exception)
81 joinBlock.Fault (exception);