mcs/class/System.Data/System.Data/XmlDiffLoader.cs

   1 //
   2 // mcs/class/System.Data/System.Data/XmlDiffLoader.cs
   3 //
   4 // Purpose: Loads XmlDiffGrams to DataSet
   5 //
   6 // class: XmlDiffLoader
   7 // assembly: System.Data.dll
   8 // namespace: System.Data
   9 //
  10 // Author:
  11 //     Ville Palo <vi64pa@koti.soon.fi>
  12 //     Lluis Sanchez Gual (lluis@ximian.com)
  13 //
  14 // (c)copyright 2003 Ville Palo
  15 //
  16
  17 //
  18 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  19 //
  20 // Permission is hereby granted, free of charge, to any person obtaining
  21 // a copy of this software and associated documentation files (the
  22 // "Software"), to deal in the Software without restriction, including
  23 // without limitation the rights to use, copy, modify, merge, publish,
  24 // distribute, sublicense, and/or sell copies of the Software, and to
  25 // permit persons to whom the Software is furnished to do so, subject to
  26 // the following conditions:
  27 //
  28 // The above copyright notice and this permission notice shall be
  29 // included in all copies or substantial portions of the Software.
  30 //
  31 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  32 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  33 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  34 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  35 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  36 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  37 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  38 //
  39 using System;
  40 using System.Data;
  41 using System.Xml;
  42 using System.Xml.Schema;
  43 using System.Xml.XPath;
  44 using System.Collections;
  45 using System.Globalization;
  46
  47 namespace System.Data {
  48
  49         internal class XmlDiffLoader
  50         {
  51
  52                 #region Fields
  53                 private DataSet DSet;
  54                 private DataTable table;
  55                 private Hashtable DiffGrRows = new Hashtable ();
  56                 private Hashtable ErrorRows = new Hashtable ();
  57
  58                 #endregion // Fields
  59
  60                 #region ctors
  61
  62                 public XmlDiffLoader (DataSet DSet)
  63                 {
  64                         this.DSet = DSet;
  65                 }
  66
  67                 public XmlDiffLoader (DataTable table)
  68                 {
  69                         this.table = table;
  70                 }
  71
  72                 #endregion //ctors
  73
  74                 #region Public methods
  75
  76                 public void Load (XmlReader reader)
  77                 {
  78                         bool origEnforceConstraint = false;
  79                         if (DSet != null) {
  80                                 origEnforceConstraint = DSet.EnforceConstraints;
  81                                 DSet.EnforceConstraints = false;
  82                         }
  83
  84                         reader.MoveToContent ();
  85                         if (reader.IsEmptyElement) {
  86                                 reader.Skip ();
  87                                 return;
  88                         }
  89
  90                         reader.ReadStartElement ("diffgram", XmlConstants.DiffgrNamespace);
  91                         reader.MoveToContent ();
  92
  93                         while (reader.NodeType != XmlNodeType.EndElement)
  94                         {
  95                                 if (reader.NodeType == XmlNodeType.Element)
  96                                 {
  97                                         if (reader.LocalName == "before" && reader.NamespaceURI == XmlConstants.DiffgrNamespace)
  98                                                 LoadBefore (reader);
  99                                         else if (reader.LocalName == "errors" && reader.NamespaceURI == XmlConstants.DiffgrNamespace)
 100                                                 LoadErrors (reader);
 101                                         else
 102                                                 LoadCurrent (reader);
 103                                 }
 104                                 else
 105                                         reader.Skip ();
 106                         }
 107
 108                         reader.ReadEndElement ();
 109
 110                         if (DSet != null)
 111                                 DSet.EnforceConstraints = origEnforceConstraint;
 112                 }
 113
 114                 #endregion // Public methods
 115
 116                 #region Private methods
 117
 118                 private void LoadCurrent (XmlReader reader)
 119                 {
 120                         if (reader.IsEmptyElement) {
 121                                 reader.Skip();
 122                                 return;
 123                         }
 124                         reader.ReadStartElement ();             // Dataset root
 125                         reader.MoveToContent ();
 126
 127                         while (reader.NodeType != XmlNodeType.EndElement)
 128                         {
 129                                 if (reader.NodeType == XmlNodeType.Element)
 130                                 {
 131                                         DataTable t = GetTable (reader.LocalName);
 132                                         if (t != null)
 133                                                 LoadCurrentTable (t, reader);
 134 #if true
 135                                         else
 136                                                 reader.Skip ();
 137 #else
 138                                         else
 139                                                 throw new DataException (Locale.GetText ("Cannot load diffGram. Table '" + reader.LocalName + "' is missing in the destination dataset"));
 140 #endif
 141                                 }
 142                                 else
 143                                         reader.Skip ();
 144                         }
 145
 146                         reader.ReadEndElement ();
 147                 }
 148
 149                 private void LoadBefore (XmlReader reader)
 150                 {
 151                         if (reader.IsEmptyElement) {
 152                                 reader.Skip ();
 153                                 return;
 154                         }
 155                         reader.ReadStartElement ();
 156                         reader.MoveToContent ();
 157
 158                         while (reader.NodeType != XmlNodeType.EndElement)
 159                         {
 160                                 if (reader.NodeType == XmlNodeType.Element)
 161                                 {
 162                                         DataTable t = GetTable (reader.LocalName);
 163                                         if (t != null)
 164                                                 LoadBeforeTable(t, reader);
 165                                         else
 166                                                 throw new DataException (Locale.GetText ("Cannot load diffGram. Table '" + reader.LocalName + "' is missing in the destination dataset"));
 167                                 }
 168                                 else
 169                                         reader.Skip ();
 170                         }
 171
 172                         reader.ReadEndElement ();
 173                 }
 174
 175
 176                 private void LoadErrors (XmlReader reader)
 177                 {
 178                         if (reader.IsEmptyElement) {
 179                                 reader.Skip ();
 180                                 return;
 181                         }
 182                         reader.ReadStartElement ();
 183                         reader.MoveToContent ();
 184
 185                         while (reader.NodeType != XmlNodeType.EndElement)
 186                         {
 187                                 if (reader.NodeType == XmlNodeType.Element)
 188                                 {
 189                                         DataRow Row = null;
 190
 191                                         // find the row in 'current' section
 192
 193                                         string id = reader.GetAttribute ("id", XmlConstants.DiffgrNamespace);
 194
 195                                         if (id != null)
 196                                                 Row = (DataRow) ErrorRows [id];
 197
 198                                         if (reader.IsEmptyElement) continue;
 199                                         reader.ReadStartElement ();
 200                                         while (reader.NodeType != XmlNodeType.EndElement)
 201                                         {
 202                                                 if (reader.NodeType == XmlNodeType.Element) {
 203                                                         string error = reader.GetAttribute ("Error", XmlConstants.DiffgrNamespace);
 204                                                         Row.SetColumnError (reader.LocalName, error);
 205                                                 }
 206                                                 reader.Read ();
 207                                         }
 208                                 }
 209                                 else
 210                                         reader.Skip ();
 211                         }
 212                         reader.ReadEndElement ();
 213                 }
 214
 215                 private void LoadColumns (DataTable Table, DataRow Row,
 216                         XmlReader reader, DataRowVersion loadType)
 217                 {
 218                         // attributes
 219                         LoadColumnAttributes (Table, Row, reader, loadType);
 220                         LoadColumnChildren (Table, Row, reader, loadType);
 221                 }
 222
 223                 private void LoadColumnAttributes (DataTable Table, DataRow Row,
 224                         XmlReader reader, DataRowVersion loadType)
 225                 {
 226                         if (!reader.HasAttributes // this check will be faster
 227                                 || !reader.MoveToFirstAttribute ())
 228                                 return;
 229                         do {
 230                                 switch (reader.NamespaceURI) {
 231                                 case XmlConstants.XmlnsNS:
 232                                 case XmlConstants.DiffgrNamespace:
 233                                 case XmlConstants.MsdataNamespace:
 234                                 case XmlConstants.MspropNamespace:
 235                                 case XmlSchema.Namespace:
 236                                         continue;
 237                                 }
 238                                 DataColumn c = Table.Columns [reader.LocalName];
 239                                 if (c == null ||
 240                                         c.ColumnMapping != MappingType.Attribute)                                       continue;
 241                                 if (c.Namespace == null && reader.NamespaceURI == String.Empty ||
 242                                         c.Namespace == reader.NamespaceURI) {
 243                                         object data = XmlDataLoader.StringToObject (c.DataType, reader.Value);
 244                                         if (loadType == DataRowVersion.Current)
 245                                                 Row [c] = data;
 246                                         else
 247                                                 Row.SetOriginalValue (c.ColumnName, data);
 248                                 } // otherwise just ignore as well as unknown elements.
 249                         } while (reader.MoveToNextAttribute ());
 250                         reader.MoveToElement ();
 251                 }
 252
 253                 private void LoadColumnChildren (DataTable Table, DataRow Row,
 254                         XmlReader reader, DataRowVersion loadType)
 255                 {
 256                         // children
 257                         if (reader.IsEmptyElement) {
 258                                 reader.Skip ();
 259                                 return;
 260                         }
 261                         reader.ReadStartElement ();
 262                         reader.MoveToContent ();
 263
 264                         while (reader.NodeType != XmlNodeType.EndElement)
 265                         {
 266                                 if (reader.NodeType != XmlNodeType.Element) { reader.Read (); continue; }
 267
 268                                 if (Table.Columns.Contains (reader.LocalName))
 269                                 {
 270                                         string colName = reader.LocalName;
 271                                         object data = XmlDataLoader.StringToObject (Table.Columns[colName].DataType, reader.ReadString ());
 272
 273                                         if (loadType == DataRowVersion.Current) Row [colName] = data;
 274                                         else Row.SetOriginalValue (colName, data);
 275                                         reader.Read ();
 276                                 }
 277                                 else
 278                                 {
 279                                         DataTable t = GetTable (reader.LocalName);
 280                                         if (t != null) {
 281                                                 if (loadType == DataRowVersion.Original)
 282                                                         LoadBeforeTable (t, reader);
 283                                                 else if (loadType == DataRowVersion.Current)
 284                                                         LoadCurrentTable (t, reader);
 285                                         }
 286                                 }
 287                         }
 288
 289                         reader.ReadEndElement ();
 290                 }
 291
 292                 private void LoadBeforeTable (DataTable Table, XmlReader reader)
 293                 {
 294                         string id = reader.GetAttribute ("id", XmlConstants.DiffgrNamespace);
 295                         string rowOrder = reader.GetAttribute ("rowOrder", XmlConstants.MsdataNamespace);
 296                         DataRow Row = (DataRow) DiffGrRows [id];
 297
 298                         if (Row == null)
 299                         {
 300                                 // Deleted row
 301                                 Row = Table.NewRow ();
 302                                 LoadColumns (Table, Row, reader, DataRowVersion.Current);
 303                                 Table.Rows.InsertAt (Row, int.Parse (rowOrder));
 304                                 Row.AcceptChanges ();
 305                                 Row.Delete ();
 306                         }
 307                         else
 308                         {
 309                                 LoadColumns (Table, Row, reader, DataRowVersion.Original);
 310                         }
 311                 }
 312
 313                 private void LoadCurrentTable (DataTable Table, XmlReader reader)
 314                 {
 315                         DataRowState state;
 316                         DataRow Row = Table.NewRow ();
 317
 318                         string id = reader.GetAttribute  ("id", XmlConstants.DiffgrNamespace);
 319                         string error = reader.GetAttribute ("hasErrors");
 320                         string changes = reader.GetAttribute ("hasChanges", XmlConstants.DiffgrNamespace);
 321
 322                         if (changes != null)
 323                         {
 324                                 if (string.Compare (changes, "modified", true) == 0) {
 325                                         DiffGrRows.Add (id, Row); // for later use
 326                                         state = DataRowState.Modified;
 327                                 }
 328                                 else if (string.Compare (changes, "inserted", true) == 0) {
 329                                         state = DataRowState.Added;
 330                                 }
 331                                 else
 332                                         throw new InvalidOperationException ("Invalid row change state");
 333                         }
 334                         else
 335                                 state = DataRowState.Unchanged;
 336
 337                         // If row had errors add row to hashtable for later use
 338                         if (error != null && string.Compare (error, "true", true) == 0)
 339                                 ErrorRows.Add (id, Row);
 340
 341                         LoadColumns (Table, Row, reader, DataRowVersion.Current);
 342                         Table.Rows.Add (Row);
 343
 344                         if (state != DataRowState.Added)
 345                                 Row.AcceptChanges ();
 346                 }
 347
 348                 DataTable GetTable (string name)
 349                 {
 350                         if (DSet != null)
 351                                 return DSet.Tables [name];
 352                         else if (name == table.TableName)
 353                                 return table;
 354                         else
 355                                 return null;
 356                 }
 357
 358
 359                 #endregion // Private methods
 360         }
 361 }