mcs/class/System.Threading.Tasks.Dataflow/System.Threading.Tasks.Dataflow/ActionBlock.cs

   1 // ActionBlock.cs
   2 //
   3 // Copyright (c) 2011 Jérémie "garuma" Laval
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining a copy
   6 // of this software and associated documentation files (the "Software"), to deal
   7 // in the Software without restriction, including without limitation the rights
   8 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9 // copies of the Software, and to permit persons to whom the Software is
  10 // furnished to do so, subject to the following conditions:
  11 //
  12 // The above copyright notice and this permission notice shall be included in
  13 // all copies or substantial portions of the Software.
  14 //
  15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21 // THE SOFTWARE.
  22 //
  23 //
  24
  25
  26 using System;
  27 using System.Threading;
  28 using System.Threading.Tasks;
  29 using System.Collections.Concurrent;
  30
  31 namespace System.Threading.Tasks.Dataflow
  32 {
  33         public sealed class ActionBlock<TInput> : ITargetBlock<TInput>, IDataflowBlock
  34         {
  35                 static readonly ExecutionDataflowBlockOptions defaultOptions = new ExecutionDataflowBlockOptions ();
  36
  37                 CompletionHelper compHelper = CompletionHelper.GetNew ();
  38                 BlockingCollection<TInput> messageQueue = new BlockingCollection<TInput> ();
  39                 ExecutingMessageBox<TInput> messageBox;
  40                 Action<TInput> action;
  41                 ExecutionDataflowBlockOptions dataflowBlockOptions;
  42
  43
  44                 public ActionBlock (Action<TInput> action) : this (action, defaultOptions)
  45                 {
  46
  47                 }
  48
  49                 public ActionBlock (Action<TInput> action, ExecutionDataflowBlockOptions dataflowBlockOptions)
  50                 {
  51                         if (action == null)
  52                                 throw new ArgumentNullException ("action");
  53                         if (dataflowBlockOptions == null)
  54                                 throw new ArgumentNullException ("dataflowBlockOptions");
  55
  56                         this.action = action;
  57                         this.dataflowBlockOptions = dataflowBlockOptions;
  58                         this.messageBox = new ExecutingMessageBox<TInput> (messageQueue, compHelper, () => true, ProcessQueue, dataflowBlockOptions);
  59                 }
  60
  61                 [MonoTODO]
  62                 public ActionBlock (Func<TInput, Task> action) : this (action, defaultOptions)
  63                 {
  64                         throw new NotImplementedException ();
  65                 }
  66
  67                 [MonoTODO]
  68                 public ActionBlock (Func<TInput, Task> action, ExecutionDataflowBlockOptions dataflowBlockOptions)
  69                 {
  70                         throw new NotImplementedException ();
  71                 }
  72
  73                 public DataflowMessageStatus OfferMessage (DataflowMessageHeader messageHeader,
  74                                                            TInput messageValue,
  75                                                            ISourceBlock<TInput> source,
  76                                                            bool consumeToAccept)
  77                 {
  78                         return messageBox.OfferMessage (this, messageHeader, messageValue, source, consumeToAccept);
  79                 }
  80
  81                 void ProcessQueue ()
  82                 {
  83                         TInput data;
  84                         while (messageQueue.TryTake (out data))
  85                                 action (data);
  86                 }
  87
  88                 public void Complete ()
  89                 {
  90                         messageBox.Complete ();
  91                 }
  92
  93                 public void Fault (Exception ex)
  94                 {
  95                         compHelper.Fault (ex);
  96                 }
  97
  98                 public Task Completion {
  99                         get {
 100                                 return compHelper.Completion;
 101                         }
 102                 }
 103
 104                 public int InputCount {
 105                         get {
 106                                 return messageQueue.Count;
 107                         }
 108                 }
 109         }
 110 }
 111