mcs/class/IBM.Data.DB2/IBM.Data.DB2/DB2Connection.cs

   1
   2 //
   3 // Permission is hereby granted, free of charge, to any person obtaining
   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
   6 // without limitation the rights to use, copy, modify, merge, publish,
   7 // distribute, sublicense, and/or sell copies of the Software, and to
   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 using System;
  23 using System.Collections;
  24 using System.Collections.Specialized;
  25 using System.Data;
  26 using System.Runtime.InteropServices;
  27 using System.Text;
  28
  29 namespace IBM.Data.DB2
  30 {
  31
  32
  33         public class DB2Connection : System.ComponentModel.Component, IDbConnection, ICloneable
  34         {
  35                 #region private data members
  36
  37                 private ArrayList refCommands;\r
  38                 private WeakReference refTransaction;\r
  39                 private DB2ConnectionSettings connectionSettings = null;\r
  40                 private int connectionTimeout;\r
  41                 internal DB2OpenConnection openConnection;\r
  42                 private bool disposed = false;
  43
  44                 #endregion
  45
  46                 #region Constructors
  47
  48                 public DB2Connection()
  49                 {
  50                         connectionTimeout = 15;
  51
  52                 }
  53
  54                 public DB2Connection(string conString)
  55                 {
  56
  57                         SetConnectionString(conString);
  58                 }
  59
  60
  61                 #endregion
  62
  63                 #region ConnectionString property
  64
  65                 public string ConnectionString
  66                 {
  67                         get
  68                         {
  69                                 return connectionSettings.ConnectionString;
  70                         }
  71                         set
  72                         {
  73                                 SetConnectionString(value);
  74                         }
  75                 }
  76                 #endregion
  77
  78
  79                 #region ConnectionTimeout property
  80                 public int ConnectionTimeout
  81                 {
  82                         get
  83                         {
  84                                 return connectionTimeout;
  85                         }
  86                         set
  87                         {
  88                                 connectionTimeout = value;
  89                         }
  90                 }
  91                 #endregion
  92
  93                 #region Database property
  94                 public string Database
  95                 {
  96                         get
  97                         {
  98                                 return connectionSettings.DatabaseAlias;
  99                         }
 100                 }
 101                 #endregion
 102
 103                 #region State property
 104
 105
 106                 unsafe public ConnectionState State
 107                 {
 108                         get
 109                         {
 110                                 //if ((long)dbHandle.ToPointer() == DB2Constants.SQL_NULL_HANDLE)
 111                                 if (openConnection == null)
 112                                         return ConnectionState.Closed;
 113                                 return ConnectionState.Open;
 114                         }
 115                 }
 116                 #endregion
 117
 118                 #region events\r
 119 \r
 120                 public event DB2InfoMessageEventHandler InfoMessage;\r
 121                 public event StateChangeEventHandler StateChange;\r
 122 \r
 123                 internal void OnInfoMessage(short handleType, IntPtr handle)\r
 124                 {\r
 125                         if(InfoMessage != null)\r
 126                         {\r
 127                                 // Don't get error information until we know for sure someone is listening\r
 128                                 try\r
 129                                 {\r
 130                                         InfoMessage(this,\r
 131                                                 new DB2InfoMessageEventArgs(new DB2ErrorCollection(handleType, handle)));\r
 132                                 }\r
 133                                 catch(Exception)\r
 134                                 {}\r
 135                         }\r
 136                 }\r
 137 \r
 138                 private void OnStateChange(StateChangeEventArgs args)\r
 139                 {\r
 140                         if(StateChange != null)\r
 141                                 StateChange(this, args);\r
 142                 }\r
 143 \r
 144                 #endregion
 145
 146                 #region DBHandle
 147
 148                 internal IntPtr DBHandle
 149                 {
 150                         get
 151                         {
 152                                 return (openConnection == null) ? IntPtr.Zero : openConnection.DBHandle;
 153                         }
 154                 }
 155                 #endregion
 156
 157                 #region BeginTransaction Method
 158
 159                 IDbTransaction IDbConnection.BeginTransaction()
 160                 {
 161                         return BeginTransaction();
 162                 }
 163
 164                 IDbTransaction IDbConnection.BeginTransaction(IsolationLevel isolationL)
 165                 {
 166                         return BeginTransaction(isolationL);
 167                 }
 168
 169                 public DB2Transaction BeginTransaction()
 170                 {
 171                         return BeginTransaction(IsolationLevel.ReadCommitted);
 172                 }
 173
 174                 public DB2Transaction BeginTransaction(IsolationLevel isolationL)
 175                 {\r
 176                         if ((refTransaction != null) && (refTransaction.IsAlive))\r
 177                                 throw new InvalidOperationException("Cannot open another transaction");\r
 178                         if(State != ConnectionState.Open)\r
 179                                 throw new InvalidOperationException("BeginTransaction needs an open connection");\r
 180 \r
 181                         if(refTransaction != null)\r
 182                         {\r
 183                                 if(refTransaction.IsAlive)\r
 184                                         throw new InvalidOperationException("Parallel transactions not supported");\r
 185 \r
 186                                 openConnection.RollbackDeadTransaction();\r
 187                                 refTransaction = null;\r
 188                         }\r
 189                         openConnection.transactionOpen = true;\r
 190                         DB2Transaction tran = new DB2Transaction(this, isolationL);\r
 191                         refTransaction = new WeakReference(tran);\r
 192                         return tran;\r
 193                 }
 194
 195                 #endregion
 196
 197                 #region ChangeDatabase
 198                 unsafe public void ChangeDatabase(string newDBName)\r
 199                 {\r
 200                         if(connectionSettings == null)\r
 201                         {\r
 202                                 throw new InvalidOperationException("No connection string");\r
 203                         }\r
 204                         this.Close();\r
 205 \r
 206                         SetConnectionString(connectionSettings.ConnectionString.Replace(connectionSettings.DatabaseAlias, newDBName));\r
 207 \r
 208                         this.Open();\r
 209                 }
 210                 #endregion
 211
 212                 #region ReleaseObjectPool
 213                 public static void ReleaseObjectPool()\r
 214                 {\r
 215                         DB2Environment.Instance.Dispose();\r
 216                 }
 217                 #endregion
 218
 219                 #region Close
 220                 public void Close()\r
 221                 {\r
 222                         DB2Transaction transaction = null;\r
 223                         if(refTransaction != null)\r
 224                                 transaction = (DB2Transaction)refTransaction.Target;\r
 225                         if((transaction != null) && refTransaction.IsAlive)\r
 226                         {\r
 227                                 transaction.Dispose();\r
 228                         }\r
 229                         if(refCommands != null)\r
 230                         {\r
 231                                 for(int i = 0; i < refCommands.Count; i++)\r
 232                                 {\r
 233                                         DB2Command command = null;\r
 234                                         if(refCommands[i] != null)\r
 235                                         {\r
 236                                                 command = (DB2Command)((WeakReference)refCommands[i]).Target;\r
 237                                         }\r
 238                                         if((command != null) && ((WeakReference)refCommands[i]).IsAlive)\r
 239                                         {\r
 240                                                 try\r
 241                                                 {\r
 242                                                         command.ConnectionClosed();\r
 243                                                 }\r
 244                                                 catch{}\r
 245                                         }\r
 246                                         //?? refCommands[i] = null;\r
 247                                 }\r
 248                         }\r
 249 \r
 250                         if(openConnection != null)\r
 251                         {\r
 252                                 openConnection.Close();\r
 253                                 openConnection = null;\r
 254                         }\r
 255                 }\r
 256
 257                 #endregion
 258
 259                 #region CreateCommand
 260                 IDbCommand IDbConnection.CreateCommand()
 261                 {
 262                         return CreateCommand();
 263                 }
 264
 265                 public DB2Command CreateCommand()
 266                 {
 267                         //CheckState();
 268                         return new DB2Command(null, this);
 269                 }
 270                 #endregion
 271
 272                 #region Open
 273
 274                 unsafe public void Open()\r
 275                 {\r
 276                         if(disposed)\r
 277                         {\r
 278                                 throw new ObjectDisposedException("DB2Connection");\r
 279                         }\r
 280 \r
 281                         if (this.State == ConnectionState.Open || this.State == ConnectionState.Connecting || this.State == ConnectionState.Executing || this.State == ConnectionState.Fetching)\r
 282                         {\r
 283                                 throw new InvalidOperationException("Connection already open");\r
 284                         }\r
 285 \r
 286                         try\r
 287                         {\r
 288                                 openConnection = connectionSettings.GetRealOpenConnection(this);\r
 289                         }\r
 290                         catch (DB2Exception)\r
 291                         {\r
 292                                 Close();\r
 293                                 throw;\r
 294                         }\r
 295                 }
 296                 #endregion
 297
 298                 #region Dispose
 299                 public new void Dispose()\r
 300                 {\r
 301                         Dispose(true);\r
 302                         GC.SuppressFinalize(this);\r
 303                 }\r
 304 \r
 305                 protected override void Dispose(bool disposing)\r
 306                 {\r
 307                         if(!disposed) \r
 308                         {\r
 309                                 if(disposing)\r
 310                                 {\r
 311                                         // dispose managed resources\r
 312                                         Close();\r
 313                                 }\r
 314                         }\r
 315                         base.Dispose(disposing);\r
 316                         disposed = true;\r
 317                 }\r
 318 \r
 319 \r
 320                 ~DB2Connection()\r
 321                 {\r
 322                         Dispose(false);\r
 323                 }
 324                 #endregion
 325
 326                 private void CheckState()\r
 327                 {\r
 328                         if (ConnectionState.Closed == State)\r
 329                                 throw new InvalidOperationException("Connection is currently closed.");\r
 330                 }\r
 331 \r
 332                 void SetConnectionString (string connectionString) \r
 333                 {\r
 334                         if (State != ConnectionState.Closed)\r
 335                                 throw new InvalidOperationException("Connection is not closed.");\r
 336 \r
 337                         this.connectionSettings = DB2ConnectionSettings.GetConnectionSettings(connectionString);\r
 338                 }\r
 339 \r
 340                 internal WeakReference WeakRefTransaction\r
 341                 {\r
 342                         get\r
 343                         {\r
 344                                 return refTransaction;\r
 345                         }\r
 346                         set\r
 347                         {\r
 348                                 refTransaction = value;\r
 349                         }\r
 350 \r
 351                 }\r
 352 \r
 353                 internal void AddCommand(DB2Command command)\r
 354                 {\r
 355                         if(refCommands == null)\r
 356                         {\r
 357                                 refCommands = new ArrayList();\r
 358                         }\r
 359                         for(int i = 0; i < refCommands.Count; i++)\r
 360                         {\r
 361                                 WeakReference reference = (WeakReference)refCommands[i];\r
 362                                 if((reference == null) || !reference.IsAlive)\r
 363                                 {\r
 364                                         refCommands[i] = new WeakReference(command);\r
 365                                         return;\r
 366                                 }\r
 367                         }\r
 368                         refCommands.Add(new WeakReference(command));\r
 369 \r
 370                 }\r
 371 \r
 372                 internal void RemoveCommand(DB2Command command)\r
 373                 {\r
 374                         for(int i = 0; i < refCommands.Count; i++)\r
 375                         {\r
 376                                 WeakReference reference = (WeakReference)refCommands[i];\r
 377                                 if(object.ReferenceEquals(reference, command))\r
 378                                 {\r
 379                                         refCommands[i] = null;\r
 380                                         return;\r
 381                                 }\r
 382                         }\r
 383                 }
 384
 385                 #region ICloneable Members\r
 386 \r
 387                 object ICloneable.Clone()\r
 388                 {\r
 389                         DB2Connection clone = new DB2Connection();\r
 390 \r
 391                         clone.connectionSettings = connectionSettings;\r
 392                         clone.connectionTimeout = connectionTimeout;\r
 393                         \r
 394                         return clone;\r
 395                 }\r
 396 \r
 397                 #endregion
 398
 399         }
 400 }
 401