mcs/class/Mono.Data.TdsClient/Mono.Data.TdsClient/TdsConnectionPool.cs

   1 //
   2 // Mono.Data.TdsClient.TdsConnectionPool.cs
   3 //
   4 // Author:
   5 //   Tim Coleman (tim@timcoleman.com)
   6 //
   7 // Copyright (C) 2002 Tim Coleman
   8 //
   9
  10 using Mono.Data.TdsClient.Internal;
  11 using System;
  12 using System.Collections;
  13 using System.Threading;
  14
  15 namespace Mono.Data.TdsClient {
  16         internal class TdsConnectionPool : MarshalByRefObject, IList, ICollection, IEnumerable
  17         {
  18                 #region Fields
  19
  20                 ArrayList list = new ArrayList ();
  21
  22                 int maxSize;
  23                 int minSize;
  24                 int packetSize;
  25                 int port;
  26
  27                 string dataSource;
  28
  29                 #endregion // Fields
  30
  31                 #region Constructors
  32
  33                 public TdsConnectionPool (string dataSource, int port, int packetSize, int minSize, int maxSize)
  34                 {
  35                         this.dataSource = dataSource;
  36                         this.port = port;
  37                         this.packetSize = packetSize;
  38                         this.minSize = minSize;
  39                         this.maxSize = maxSize;
  40                 }
  41
  42                 #endregion // Constructors
  43
  44                 #region Properties
  45
  46                 public Tds this[int index] {
  47                         get { return (Tds) list[index]; }
  48                 }
  49
  50                 object IList.this[int index] {
  51                         get { return this[index]; }
  52                         set { throw new InvalidOperationException (); }
  53                 }
  54
  55                 public int Count {
  56                         get { return list.Count; }
  57                 }
  58
  59                 public bool IsFixedSize {
  60                         get { return false; }
  61                 }
  62
  63                 public bool IsReadOnly {
  64                         get { return true; }
  65                 }
  66
  67                 public bool IsSynchronized {
  68                         get { return false; }
  69                 }
  70
  71                 public int MaxSize {
  72                         get { return maxSize; }
  73                 }
  74
  75                 public int MinSize {
  76                         get { return minSize; }
  77                 }
  78
  79                 public object SyncRoot {
  80                         get { throw new InvalidOperationException (); }
  81                 }
  82
  83                 #endregion // Properties
  84
  85                 #region Methods
  86
  87                 public int Add (object o)
  88                 {
  89                         return list.Add ((Tds) o);
  90                 }
  91
  92                 public void Clear ()
  93                 {
  94                         list.Clear ();
  95                 }
  96
  97                 public bool Contains (object o)
  98                 {
  99                         return list.Contains ((Tds) o);
 100                 }
 101
 102                 public void CopyTo (Array array, int index)
 103                 {
 104                         list.CopyTo (array, index);
 105                 }
 106
 107                 public IEnumerator GetEnumerator ()
 108                 {
 109                         return list.GetEnumerator ();
 110                 }
 111
 112                 [MonoTODO]
 113                 public ITds AllocateConnection ()
 114                 {
 115                         // make sure we have the minimum count (really only useful the first time)
 116                         lock (list) {
 117                                 for (int i = Count; i < minSize; i += 1)
 118                                         Add (new Tds42 (dataSource, port, packetSize));
 119                         }
 120
 121                         // Try to obtain a lock
 122                         foreach (object o in list)
 123                                 if (Monitor.TryEnter (o))
 124                                         return (ITds) o;
 125
 126                         if (Count < maxSize) {
 127                                 Tds tds = new Tds42 (dataSource, port, packetSize);
 128                                 Monitor.Enter (tds);
 129                                 Add (tds);
 130                                 return tds;
 131                         }
 132
 133                         // else we have to wait for one to be available
 134
 135                         return null;
 136                 }
 137
 138                 public void ReleaseConnection (ITds tds)
 139                 {
 140                         Monitor.Exit (tds);
 141                 }
 142
 143                 public int IndexOf (object o)
 144                 {
 145                         return list.IndexOf ((Tds) o);
 146                 }
 147
 148                 public void Insert (int index, object o)
 149                 {
 150                         list.Insert (index, (Tds) o);
 151                 }
 152
 153                 public void Remove (object o)
 154                 {
 155                         list.Remove ((Tds) o);
 156                 }
 157
 158                 public void RemoveAt (int index)
 159                 {
 160                         list.RemoveAt (index);
 161                 }
 162
 163                 #endregion // Methods
 164         }
 165 }