mcs/class/FirebirdSql.Data.Firebird/FirebirdSql.Data.Common/ArrayBase.cs

   1 /*
   2  *  Firebird ADO.NET Data provider for .NET and Mono
   3  *
   4  *     The contents of this file are subject to the Initial
   5  *     Developer's Public License Version 1.0 (the "License");
   6  *     you may not use this file except in compliance with the
   7  *     License. You may obtain a copy of the License at
   8  *     http://www.firebirdsql.org/index.php?op=doc&id=idpl
   9  *
  10  *     Software distributed under the License is distributed on
  11  *     an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either
  12  *     express or implied.  See the License for the specific
  13  *     language governing rights and limitations under the License.
  14  *
  15  *  Copyright (c) 2002, 2005 Carlos Guzman Alvarez
  16  *  All Rights Reserved.
  17  */
  18
  19 using System;
  20 using System.Text;
  21 using System.Globalization;
  22
  23 namespace FirebirdSql.Data.Common
  24 {
  25         internal abstract class ArrayBase
  26         {
  27                 #region Fields
  28
  29                 private ArrayDesc       descriptor;
  30                 private string          tableName;
  31                 private string          fieldName;
  32                 private string          rdbFieldName;
  33
  34                 #endregion
  35
  36                 #region Properties
  37
  38                 public ArrayDesc Descriptor
  39                 {
  40                         get { return this.descriptor; }
  41                 }
  42
  43                 #endregion
  44
  45                 #region Abstract Properties
  46
  47                 public abstract long Handle
  48                 {
  49                         get;
  50                         set;
  51                 }
  52
  53                 public abstract IDatabase DB
  54                 {
  55                         get;
  56                         set;
  57                 }
  58
  59                 public abstract ITransaction Transaction
  60                 {
  61                         get;
  62                         set;
  63                 }
  64
  65                 #endregion
  66
  67                 #region Constructors
  68
  69                 protected ArrayBase(ArrayDesc descriptor)
  70                 {
  71                         this.tableName  = descriptor.RelationName;
  72                         this.fieldName  = descriptor.FieldName;
  73                         this.descriptor = descriptor;
  74                 }
  75
  76                 protected ArrayBase(string tableName, string fieldName)
  77                 {
  78                         this.tableName          = tableName;
  79                         this.fieldName          = fieldName;
  80                         this.rdbFieldName       = String.Empty;
  81                 }
  82
  83                 #endregion
  84
  85                 #region Abstract Methods
  86
  87                 public abstract byte[] GetSlice(int slice_length);
  88                 public abstract void PutSlice(System.Array source_array, int slice_length);
  89
  90                 #endregion
  91
  92                 #region Protected Abstract Methods
  93
  94                 protected abstract System.Array DecodeSlice(byte[] slice);
  95
  96                 #endregion
  97
  98                 #region Methods
  99
 100                 public Array Read()
 101                 {
 102                         byte[] slice = this.GetSlice(this.GetSliceLength(true));
 103
 104                         return this.DecodeSlice(slice);
 105                 }
 106
 107                 public void Write(System.Array sourceArray)
 108                 {
 109                         this.SetDesc(sourceArray);
 110                         this.PutSlice(sourceArray, this.GetSliceLength(false));
 111                 }
 112
 113                 public void SetDesc(System.Array sourceArray)
 114                 {
 115                         this.descriptor.Dimensions = (short)sourceArray.Rank;
 116
 117                         for (int i = 0; i < sourceArray.Rank; i++)
 118                         {
 119                                 int lb = this.descriptor.Bounds[i].LowerBound;
 120                                 int ub = sourceArray.GetLength(i) - 1 + lb;
 121
 122                                 this.descriptor.Bounds[i].UpperBound = ub;
 123                         }
 124                 }
 125
 126                 public void LookupBounds()
 127                 {
 128                         this.LookupDesc();
 129
 130                         StatementBase lookup = this.DB.CreateStatement(this.Transaction);
 131
 132                         lookup.Prepare(this.GetArrayBounds());
 133                         lookup.Execute();
 134
 135                         int i = 0;
 136                         this.descriptor.Bounds = new ArrayBound[16];
 137                         DbValue[] values;
 138
 139                         while ((values = lookup.Fetch()) != null)
 140                         {
 141                                 this.descriptor.Bounds[i].LowerBound = values[0].GetInt32();
 142                                 this.descriptor.Bounds[i].UpperBound = values[1].GetInt32();
 143
 144                                 i++;
 145                         }
 146
 147                         lookup.Release();
 148                         lookup = null;
 149                 }
 150
 151                 public void LookupDesc()
 152                 {
 153                         // Initializa array descriptor information
 154                         this.descriptor = new ArrayDesc();
 155
 156                         // Create statement for retrieve information
 157                         StatementBase lookup = this.DB.CreateStatement(this.Transaction);
 158
 159                         lookup.Prepare(this.GetArrayDesc());
 160                         lookup.Execute();
 161
 162                         DbValue[] values = lookup.Fetch();
 163                         if (values != null && values.Length > 0)
 164                         {
 165                                 this.descriptor.RelationName    = tableName;
 166                                 this.descriptor.FieldName               = fieldName;
 167                                 this.descriptor.DataType                = values[0].GetByte();
 168                                 this.descriptor.Scale                   = values[1].GetInt16();
 169                                 this.descriptor.Length                  = values[2].GetInt16();
 170                                 this.descriptor.Dimensions              = values[3].GetInt16();
 171                                 this.descriptor.Flags                   = 0;
 172
 173                                 this.rdbFieldName = values[4].GetString().Trim();
 174                         }
 175                         else
 176                         {
 177                                 throw new InvalidOperationException();
 178                         }
 179
 180                         lookup.Release();
 181                         lookup = null;
 182                 }
 183
 184                 #endregion
 185
 186                 #region Protected Methods
 187
 188                 protected int GetSliceLength(bool read)
 189                 {
 190                         int length = 0;
 191                         int elements = 0;
 192
 193                         for (int i = 0; i < this.descriptor.Dimensions; i++)
 194                         {
 195                                 ArrayBound bound = this.descriptor.Bounds[i];
 196
 197                                 elements += (bound.UpperBound - bound.LowerBound) + 1;
 198                         }
 199
 200                         length = elements * this.descriptor.Length;
 201
 202                         switch (this.descriptor.DataType)
 203                         {
 204                                 case IscCodes.blr_varying:
 205                                 case IscCodes.blr_varying2:
 206                                         length += elements * 2;
 207                                         break;
 208                         }
 209
 210                         return length;
 211                 }
 212
 213                 protected Type GetSystemType()
 214                 {
 215                         Type systemType;
 216
 217                         switch (this.descriptor.DataType)
 218                         {
 219                                 case IscCodes.blr_text:
 220                                 case IscCodes.blr_text2:
 221                                 case IscCodes.blr_cstring:
 222                                 case IscCodes.blr_cstring2:
 223                                         // Char
 224                                         systemType = typeof(System.String);
 225                                         break;
 226
 227                                 case IscCodes.blr_varying:
 228                                 case IscCodes.blr_varying2:
 229                                         // VarChar
 230                                         systemType = typeof(System.String);
 231                                         break;
 232
 233                                 case IscCodes.blr_short:
 234                                         // Short/Smallint
 235                                         if (this.descriptor.Scale < 0)
 236                                         {
 237                                                 systemType = typeof(System.Decimal);
 238                                         }
 239                                         else
 240                                         {
 241                                                 systemType = typeof(System.Int16);
 242                                         }
 243                                         break;
 244
 245                                 case IscCodes.blr_long:
 246                                         // Integer
 247                                         if (this.descriptor.Scale < 0)
 248                                         {
 249                                                 systemType = typeof(System.Decimal);
 250                                         }
 251                                         else
 252                                         {
 253                                                 systemType = typeof(System.Int32);
 254                                         }
 255                                         break;
 256
 257                                 case IscCodes.blr_float:
 258                                         // Float
 259                                         systemType = typeof(System.Single);
 260                                         break;
 261
 262                                 case IscCodes.blr_double:
 263                                 case IscCodes.blr_d_float:
 264                                         // Double
 265                                         systemType = typeof(System.Double);
 266                                         break;
 267
 268                                 case IscCodes.blr_quad:
 269                                 case IscCodes.blr_int64:
 270                                         // Long/Quad
 271                                         if (this.descriptor.Scale < 0)
 272                                         {
 273                                                 systemType = typeof(System.Decimal);
 274                                         }
 275                                         else
 276                                         {
 277                                                 systemType = typeof(System.Int64);
 278                                         }
 279                                         break;
 280
 281                                 case IscCodes.blr_timestamp:
 282                                         // Timestamp
 283                                         systemType = typeof(System.DateTime);
 284                                         break;
 285
 286                                 case IscCodes.blr_sql_time:
 287                                         // Time
 288                                         systemType = typeof(System.DateTime);
 289                                         break;
 290
 291                                 case IscCodes.blr_sql_date:
 292                                         // Date
 293                                         systemType = typeof(System.DateTime);
 294                                         break;
 295
 296                                 default:
 297                                         throw new NotSupportedException("Unknown data type");
 298                         }
 299
 300                         return systemType;
 301                 }
 302
 303                 #endregion
 304
 305                 #region Private Methods
 306
 307                 private string GetArrayDesc()
 308                 {
 309                         StringBuilder sql = new StringBuilder();
 310
 311                         sql.Append(
 312                                 "SELECT Y.RDB$FIELD_TYPE, Y.RDB$FIELD_SCALE, Y.RDB$FIELD_LENGTH, Y.RDB$DIMENSIONS, X.RDB$FIELD_SOURCE " +
 313                                 "FROM RDB$RELATION_FIELDS X, RDB$FIELDS Y " +
 314                                 "WHERE X.RDB$FIELD_SOURCE = Y.RDB$FIELD_NAME ");
 315
 316                         if (this.tableName != null && this.tableName.Length != 0)
 317                         {
 318                                 sql.AppendFormat(
 319                                         CultureInfo.CurrentCulture, " AND X.RDB$RELATION_NAME = '{0}'", tableName);
 320                         }
 321
 322                         if (this.fieldName != null && this.fieldName.Length != 0)
 323                         {
 324                                 sql.AppendFormat(
 325                                         CultureInfo.CurrentCulture, " AND X.RDB$FIELD_NAME = '{0}'", fieldName);
 326                         }
 327
 328                         return sql.ToString();
 329                 }
 330
 331                 private string GetArrayBounds()
 332                 {
 333                         StringBuilder sql = new StringBuilder();
 334
 335                         sql.Append("SELECT X.RDB$LOWER_BOUND, X.RDB$UPPER_BOUND FROM RDB$FIELD_DIMENSIONS X ");
 336
 337                         if (this.fieldName != null && this.fieldName.Length != 0)
 338                         {
 339                                 sql.AppendFormat(
 340                                         CultureInfo.CurrentCulture, "WHERE X.RDB$FIELD_NAME = '{0}'", rdbFieldName);
 341                         }
 342
 343                         sql.Append(" ORDER BY X.RDB$DIMENSION");
 344
 345                         return sql.ToString();
 346                 }
 347
 348                 #endregion
 349         }
 350 }