class/System/System.Runtime.InteropServices/HandleCollector.cs

   1 //
   2 // HandleCollector.cs
   3 //
   4 // Author: Atsushi Enomoto  <atsushi@ximian.com>
   5 //
   6 // Copyright (C) 2007 Novell, Inc (http://www.novell.com)
   7 //
   8 // Permission is hereby granted, free of charge, to any person obtaining
   9 // a copy of this software and associated documentation files (the
  10 // "Software"), to deal in the Software without restriction, including
  11 // without limitation the rights to use, copy, modify, merge, publish,
  12 // distribute, sublicense, and/or sell copies of the Software, and to
  13 // permit persons to whom the Software is furnished to do so, subject to
  14 // the following conditions:
  15 //
  16 // The above copyright notice and this permission notice shall be
  17 // included in all copies or substantial portions of the Software.
  18 //
  19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  20 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  23 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  24 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  25 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26 //
  27
  28 #if NET_2_0
  29
  30 using System;
  31
  32 namespace System.Runtime.InteropServices
  33 {
  34         public sealed class HandleCollector
  35         {
  36                 int count;
  37                 readonly int init, max;
  38                 readonly string name;
  39                 DateTime previous_collection = DateTime.MinValue;
  40
  41                 public HandleCollector (string name, int initialThreshold)
  42                         : this (name, initialThreshold, int.MaxValue)
  43                 {
  44                 }
  45
  46                 public HandleCollector (string name, int initialThreshold, int maximumThreshold)
  47                 {
  48                         if (initialThreshold < 0)
  49                                 throw new ArgumentOutOfRangeException ("initialThreshold", "initialThreshold must not be less than zero");
  50                         if (maximumThreshold < 0)
  51                                 throw new ArgumentOutOfRangeException ("maximumThreshold", "maximumThreshold must not be less than zero");
  52                         if (maximumThreshold < initialThreshold)
  53                                 throw new ArgumentException ("maximumThreshold must not be less than initialThreshold");
  54
  55                         this.name = name;
  56                         init = initialThreshold;
  57                         max = maximumThreshold;
  58                 }
  59
  60                 public int Count {
  61                         get { return count; }
  62                 }
  63
  64                 public int InitialThreshold {
  65                         get { return init; }
  66                 }
  67
  68                 public int MaximumThreshold {
  69                         get { return max; }
  70                 }
  71
  72                 public string Name {
  73                         get { return name; }
  74                 }
  75
  76                 public void Add ()
  77                 {
  78 /* NET_3_5
  79                         if (++count >= max)
  80                                 GC.Collect (GC.MaxGeneration, GCCollectionMode.Forced);
  81                         else if (count >= init)
  82                                 GC.Collect (GC.MaxGeneration, GCCollectionMode.Optimized);
  83 */
  84                         if (++count >= max)
  85                                 GC.Collect (GC.MaxGeneration);
  86                         else if (count >= init && DateTime.Now - previous_collection > TimeSpan.FromSeconds (5)) { // some arbitrary criteria
  87                                 GC.Collect (GC.MaxGeneration);
  88                                 previous_collection = DateTime.Now;
  89                         }
  90                 }
  91
  92                 public void Remove ()
  93                 {
  94                         if (count == 0)
  95                                 throw new InvalidOperationException ("Cannot call Remove method when Count is 0");
  96                         count--;
  97                 }
  98         }
  99 }
 100
 101 #endif