class/System.ComponentModel.Composition/src/ComponentModel/System/ComponentModel/Composition/Hosting/CompositionBatch.cs

   1 // -----------------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 // -----------------------------------------------------------------------
   4 using System;
   5 using System.Collections.Generic;
   6 using System.ComponentModel.Composition.Primitives;
   7 using System.Linq;
   8 using Microsoft.Internal;
   9 using System.Collections.ObjectModel;
  10 using System.Diagnostics.CodeAnalysis;
  11
  12 namespace System.ComponentModel.Composition.Hosting
  13 {
  14     public partial class CompositionBatch
  15     {
  16         private object _lock = new object();
  17         private bool _copyNeededForAdd;
  18         private bool _copyNeededForRemove;
  19         private List<ComposablePart> _partsToAdd;
  20         private ReadOnlyCollection<ComposablePart> _readOnlyPartsToAdd;
  21         private List<ComposablePart> _partsToRemove;
  22         private ReadOnlyCollection<ComposablePart> _readOnlyPartsToRemove;
  23
  24         /// <summary>
  25         /// Initializes a new instance of the <see cref="CompositionBatch"/> class.
  26         /// </summary>
  27         public CompositionBatch() :
  28             this(null, null)
  29         {
  30         }
  31
  32         /// <summary>
  33         /// Initializes a new instance of the <see cref="CompositionBatch"/> class.
  34         /// </summary>
  35         /// <param name="partsToAdd">The parts to add.</param>
  36         /// <param name="partsToRemove">The parts to remove.</param>
  37         public CompositionBatch(IEnumerable<ComposablePart> partsToAdd, IEnumerable<ComposablePart> partsToRemove)
  38         {
  39             this._partsToAdd = new List<ComposablePart>();
  40             if (partsToAdd != null)
  41             {
  42                 foreach (var part in partsToAdd)
  43                 {
  44                     if (part == null)
  45                     {
  46                         throw ExceptionBuilder.CreateContainsNullElement("partsToAdd");
  47                     }
  48                     this._partsToAdd.Add(part);
  49                 }
  50             }
  51             this._readOnlyPartsToAdd = this._partsToAdd.AsReadOnly();
  52
  53             this._partsToRemove = new List<ComposablePart>();
  54             if (partsToRemove != null)
  55             {
  56                 foreach (var part in partsToRemove)
  57                 {
  58                     if (part == null)
  59                     {
  60                         throw ExceptionBuilder.CreateContainsNullElement("partsToRemove");
  61                     }
  62                     this._partsToRemove.Add(part);
  63                 }
  64             }
  65             this._readOnlyPartsToRemove = this._partsToRemove.AsReadOnly();
  66         }
  67
  68         /// <summary>
  69         /// Returns the collection of parts that will be added.
  70         /// </summary>
  71         /// <value>The parts to be added.</value>
  72         public ReadOnlyCollection<ComposablePart> PartsToAdd
  73         {
  74             get
  75             {
  76                 lock (this._lock)
  77                 {
  78                     this._copyNeededForAdd = true;
  79                     return this._readOnlyPartsToAdd;
  80                 }
  81             }
  82         }
  83
  84         /// <summary>
  85         /// Returns the collection of parts that will be removed.
  86         /// </summary>
  87         /// <value>The parts to be removed.</value>
  88         public ReadOnlyCollection<ComposablePart> PartsToRemove
  89         {
  90             get
  91             {
  92                 lock (this._lock)
  93                 {
  94                     this._copyNeededForRemove = true;
  95                     return this._readOnlyPartsToRemove;
  96                 }
  97             }
  98         }
  99
 100         /// <summary>
 101         ///     Adds the specified part to the <see cref="CompositionBatch"/>.
 102         /// </summary>
 103         /// <param name="part">
 104         /// The part.
 105         /// </param>
 106         /// <exception cref="ArgumentNullException">
 107         ///     <paramref name="part"/> is <see langword="null"/>.
 108         /// </exception>
 109         public void AddPart(ComposablePart part)
 110         {
 111             Requires.NotNull(part, "part");
 112             lock (this._lock)
 113             {
 114                 if (this._copyNeededForAdd)
 115                 {
 116                     this._partsToAdd = new List<ComposablePart>(this._partsToAdd);
 117                     this._readOnlyPartsToAdd = this._partsToAdd.AsReadOnly();
 118                     this._copyNeededForAdd = false;
 119                 }
 120                 this._partsToAdd.Add(part);
 121             }
 122         }
 123
 124         /// <summary>
 125         ///     Removes the specified part from the <see cref="CompositionBatch"/>.
 126         /// </summary>
 127         /// <param name="part">
 128         /// The part.
 129         /// </param>
 130         /// <exception cref="ArgumentNullException">
 131         ///     <paramref name="part"/> is <see langword="null"/>.
 132         /// </exception>
 133         public void RemovePart(ComposablePart part)
 134         {
 135             Requires.NotNull(part, "part");
 136             lock (this._lock)
 137             {
 138                 if (this._copyNeededForRemove)
 139                 {
 140                     this._partsToRemove = new List<ComposablePart>(this._partsToRemove);
 141                     this._readOnlyPartsToRemove = this._partsToRemove.AsReadOnly();
 142                     this._copyNeededForRemove = false;
 143                 }
 144                 this._partsToRemove.Add(part);
 145             }
 146         }
 147
 148         /// <summary>
 149         ///     Adds the specified export to the <see cref="CompositionBatch"/>.
 150         /// </summary>
 151         /// <param name="export">
 152         ///     The <see cref="Export"/> to add to the <see cref="CompositionBatch"/>.
 153         /// </param>
 154         /// <returns>
 155         ///     A <see cref="ComposablePart"/> that can be used remove the <see cref="Export"/>
 156         ///     from the <see cref="CompositionBatch"/>.
 157         /// </returns>
 158         /// <exception cref="ArgumentNullException">
 159         ///     <paramref name="export"/> is <see langword="null"/>.
 160         /// </exception>
 161         /// <remarks>
 162         /// </remarks>
 163         public ComposablePart AddExport(Export export)
 164         {
 165             Requires.NotNull(export, "export");
 166
 167             ComposablePart part = new SingleExportComposablePart(export);
 168
 169             this.AddPart(part);
 170
 171             return part;
 172         }
 173     }
 174 }