mcs/class/System.Runtime.Serialization/System.Runtime.Serialization/KnownTypeCollection.cs

   1 //
   2 // KnownTypeCollection.cs
   3 //
   4 // Author:
   5 //      Atsushi Enomoto <atsushi@ximian.com>
   6 //
   7 // Copyright (C) 2005 Novell, Inc.  http://www.novell.com
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28 #if NET_2_0
  29 using System;
  30 using System.Collections;
  31 using System.Collections.Generic;
  32 using System.Collections.ObjectModel;
  33 using System.Linq;
  34 using System.Reflection;
  35 using System.Xml;
  36 using System.Xml.Schema;
  37
  38 using QName = System.Xml.XmlQualifiedName;
  39 using System.Xml.Serialization;
  40
  41 namespace System.Runtime.Serialization
  42 {
  43 /*
  44         XmlFormatter implementation design inference:
  45
  46         type definitions:
  47         - No XML Schema types are directly used. There are some maps from
  48           xs:blahType to ms:blahType where the namespaceURI for prefix "ms" is
  49           "http://schemas.microsoft.com/2003/10/Serialization/" .
  50
  51         serializable types:
  52         - An object being serialized 1) must be of type System.Object, or
  53           2) must be null, or 3) must have either a [DataContract] attribute
  54           or a [Serializable] attribute to be serializable.
  55         - When the object is either of type System.Object or null, then the
  56           XML type is "anyType".
  57         - When the object is [Serializable], then the runtime-serialization
  58           compatible object graph is written.
  59         - Otherwise the serialization is based on contract attributes.
  60           ([Serializable] takes precedence).
  61
  62         type derivation:
  63         - For type A to be serializable, the base type B of A must be
  64           serializable.
  65         - If a type which is [Serializable] and whose base type has a
  66           [DataContract], then for base type members [DataContract] is taken.
  67         - It is vice versa i.e. if the base type is [Serializable] and the
  68           derived type has a [DataContract], then [Serializable] takes place
  69           for base members.
  70
  71         known type collection:
  72         - It internally manages mapping store keyed by contract QNames.
  73           KnownTypeCollection.Add() checks if the same QName contract already
  74           exists (and raises InvalidOperationException if required).
  75
  76 */
  77         internal static class TypeExtensions
  78         {
  79                 public static T GetCustomAttribute<T> (this MemberInfo type, bool inherit)
  80                 {
  81                         var arr = type.GetCustomAttributes (typeof (T), inherit);
  82                         return arr != null && arr.Length == 1 ? (T) arr [0] : default (T);
  83                 }
  84         }
  85
  86         internal sealed class KnownTypeCollection : Collection<Type>
  87         {
  88                 internal const string MSSimpleNamespace =
  89                         "http://schemas.microsoft.com/2003/10/Serialization/";
  90                 internal const string MSArraysNamespace =
  91                         "http://schemas.microsoft.com/2003/10/Serialization/Arrays";
  92                 internal const string DefaultClrNamespaceBase =
  93                         "http://schemas.datacontract.org/2004/07/";
  94
  95                 static QName any_type, bool_type,
  96                         byte_type, date_type, decimal_type, double_type,
  97                         float_type, string_type,
  98                         short_type, int_type, long_type,
  99                         ubyte_type, ushort_type, uint_type, ulong_type,
 100                         // non-TypeCode
 101                         any_uri_type, base64_type, duration_type, qname_type,
 102                         // custom in ms nsURI schema
 103                         char_type, guid_type,
 104                         // not in ms nsURI schema
 105                         dbnull_type;
 106
 107                 static KnownTypeCollection ()
 108                 {
 109                         //any_type, bool_type,  byte_type, date_type, decimal_type, double_type,        float_type, string_type,
 110                         // short_type, int_type, long_type,     ubyte_type, ushort_type, uint_type, ulong_type,
 111                         //      any_uri_type, base64_type, duration_type, qname_type,
 112                         //      char_type, guid_type,   dbnull_type;
 113                         string s = MSSimpleNamespace;
 114                         any_type = new QName ("anyType", s);
 115                         any_uri_type = new QName ("anyURI", s);
 116                         bool_type = new QName ("boolean", s);
 117                         base64_type = new QName ("base64Binary", s);
 118                         date_type = new QName ("dateTime", s);
 119                         duration_type = new QName ("duration", s);
 120                         qname_type = new QName ("QName", s);
 121                         decimal_type = new QName ("decimal", s);
 122                         double_type = new QName ("double", s);
 123                         float_type = new QName ("float", s);
 124                         byte_type = new QName ("byte", s);
 125                         short_type = new QName ("short", s);
 126                         int_type = new QName ("int", s);
 127                         long_type = new QName ("long", s);
 128                         ubyte_type = new QName ("unsignedByte", s);
 129                         ushort_type = new QName ("unsignedShort", s);
 130                         uint_type = new QName ("unsignedInt", s);
 131                         ulong_type = new QName ("unsignedLong", s);
 132                         string_type = new QName ("string", s);
 133                         guid_type = new QName ("guid", s);
 134                         char_type = new QName ("char", s);
 135
 136                         dbnull_type = new QName ("DBNull", MSSimpleNamespace + "System");
 137                 }
 138
 139                 // FIXME: find out how QName and guid are processed
 140
 141                 internal QName GetXmlName (Type type)
 142                 {
 143                         SerializationMap map = FindUserMap (type);
 144                         if (map != null)
 145                                 return map.XmlName;
 146                         return GetPredefinedTypeName (type);
 147                 }
 148
 149                 internal static QName GetPredefinedTypeName (Type type)
 150                 {
 151                         QName name = GetPrimitiveTypeName (type);
 152                         if (name != QName.Empty)
 153                                 return name;
 154                         if (type == typeof (DBNull))
 155                                 return dbnull_type;
 156                         return QName.Empty;
 157                 }
 158
 159                 internal static QName GetPrimitiveTypeName (Type type)
 160                 {
 161                         if (type.IsGenericType && type.GetGenericTypeDefinition () == typeof (Nullable<>))
 162                                 return GetPrimitiveTypeName (type.GetGenericArguments () [0]);
 163
 164                         if (type.IsEnum)
 165                                 return QName.Empty;
 166
 167                         switch (Type.GetTypeCode (type)) {
 168                         case TypeCode.Object: // other than System.Object
 169                         case TypeCode.DBNull: // it is natively mapped, but not in ms serialization namespace.
 170                         case TypeCode.Empty:
 171                         default:
 172                                 if (type == typeof (object))
 173                                         return any_type;
 174                                 if (type == typeof (Guid))
 175                                         return guid_type;
 176                                 if (type == typeof (TimeSpan))
 177                                         return duration_type;
 178                                 if (type == typeof (byte []))
 179                                         return base64_type;
 180                                 if (type == typeof (Uri))
 181                                         return any_uri_type;
 182                                 return QName.Empty;
 183                         case TypeCode.Boolean:
 184                                 return bool_type;
 185                         case TypeCode.Byte:
 186                                 return ubyte_type;
 187                         case TypeCode.Char:
 188                                 return char_type;
 189                         case TypeCode.DateTime:
 190                                 return date_type;
 191                         case TypeCode.Decimal:
 192                                 return decimal_type;
 193                         case TypeCode.Double:
 194                                 return double_type;
 195                         case TypeCode.Int16:
 196                                 return short_type;
 197                         case TypeCode.Int32:
 198                                 return int_type;
 199                         case TypeCode.Int64:
 200                                 return long_type;
 201                         case TypeCode.SByte:
 202                                 return byte_type;
 203                         case TypeCode.Single:
 204                                 return float_type;
 205                         case TypeCode.String:
 206                                 return string_type;
 207                         case TypeCode.UInt16:
 208                                 return ushort_type;
 209                         case TypeCode.UInt32:
 210                                 return uint_type;
 211                         case TypeCode.UInt64:
 212                                 return ulong_type;
 213                         }
 214                 }
 215
 216                 internal static string PredefinedTypeObjectToString (object obj)
 217                 {
 218                         Type type = obj.GetType ();
 219                         switch (Type.GetTypeCode (type)) {
 220                         case TypeCode.Object: // other than System.Object
 221                         case TypeCode.Empty:
 222                         default:
 223                                 if (type == typeof (object))
 224                                         return String.Empty;
 225                                 if (type == typeof (Guid))
 226                                         return XmlConvert.ToString ((Guid) obj);
 227                                 if (type == typeof (TimeSpan))
 228                                         return XmlConvert.ToString ((TimeSpan) obj);
 229                                 if (type == typeof (byte []))
 230                                         return Convert.ToBase64String ((byte []) obj);
 231                                 if (type == typeof (Uri))
 232                                         return ((Uri) obj).ToString ();
 233                                 throw new Exception ("Internal error: missing predefined type serialization for type " + type.FullName);
 234                         case TypeCode.DBNull: // predefined, but not primitive
 235                                 return String.Empty;
 236                         case TypeCode.Boolean:
 237                                 return XmlConvert.ToString ((bool) obj);
 238                         case TypeCode.Byte:
 239                                 return XmlConvert.ToString ((int)((byte) obj));
 240                         case TypeCode.Char:
 241                                 return XmlConvert.ToString ((uint) (char) obj);
 242                         case TypeCode.DateTime:
 243                                 return XmlConvert.ToString ((DateTime) obj, XmlDateTimeSerializationMode.RoundtripKind);
 244                         case TypeCode.Decimal:
 245                                 return XmlConvert.ToString ((decimal) obj);
 246                         case TypeCode.Double:
 247                                 return XmlConvert.ToString ((double) obj);
 248                         case TypeCode.Int16:
 249                                 return XmlConvert.ToString ((short) obj);
 250                         case TypeCode.Int32:
 251                                 return XmlConvert.ToString ((int) obj);
 252                         case TypeCode.Int64:
 253                                 return XmlConvert.ToString ((long) obj);
 254                         case TypeCode.SByte:
 255                                 return XmlConvert.ToString ((sbyte) obj);
 256                         case TypeCode.Single:
 257                                 return XmlConvert.ToString ((float) obj);
 258                         case TypeCode.String:
 259                                 return (string) obj;
 260                         case TypeCode.UInt16:
 261                                 return XmlConvert.ToString ((int) (ushort) obj);
 262                         case TypeCode.UInt32:
 263                                 return XmlConvert.ToString ((uint) obj);
 264                         case TypeCode.UInt64:
 265                                 return XmlConvert.ToString ((ulong) obj);
 266                         }
 267                 }
 268
 269                 // FIXME: xsd types and ms serialization types should be differentiated.
 270                 internal static Type GetPrimitiveTypeFromName (string name)
 271                 {
 272                         switch (name) {
 273                         case "anyURI":
 274                                 return typeof (Uri);
 275                         case "boolean":
 276                                 return typeof (bool);
 277                         case "base64Binary":
 278                                 return typeof (byte []);
 279                         case "dateTime":
 280                                 return typeof (DateTime);
 281                         case "duration":
 282                                 return typeof (TimeSpan);
 283                         case "QName":
 284                                 return typeof (QName);
 285                         case "decimal":
 286                                 return typeof (decimal);
 287                         case "double":
 288                                 return typeof (double);
 289                         case "float":
 290                                 return typeof (float);
 291                         case "byte":
 292                                 return typeof (sbyte);
 293                         case "short":
 294                                 return typeof (short);
 295                         case "int":
 296                                 return typeof (int);
 297                         case "long":
 298                                 return typeof (long);
 299                         case "unsignedByte":
 300                                 return typeof (byte);
 301                         case "unsignedShort":
 302                                 return typeof (ushort);
 303                         case "unsignedInt":
 304                                 return typeof (uint);
 305                         case "unsignedLong":
 306                                 return typeof (ulong);
 307                         case "string":
 308                                 return typeof (string);
 309                         case "anyType":
 310                                 return typeof (object);
 311                         case "guid":
 312                                 return typeof (Guid);
 313                         case "char":
 314                                 return typeof (char);
 315                         default:
 316                                 return null;
 317                         }
 318                 }
 319
 320
 321                 internal static object PredefinedTypeStringToObject (string s,
 322                         string name, XmlReader reader)
 323                 {
 324                         switch (name) {
 325                         case "anyURI":
 326                                 return new Uri(s,UriKind.RelativeOrAbsolute);
 327                         case "boolean":
 328                                 return XmlConvert.ToBoolean (s);
 329                         case "base64Binary":
 330                                 return Convert.FromBase64String (s);
 331                         case "dateTime":
 332                                 return XmlConvert.ToDateTime (s, XmlDateTimeSerializationMode.RoundtripKind);
 333                         case "duration":
 334                                 return XmlConvert.ToTimeSpan (s);
 335                         case "QName":
 336                                 int idx = s.IndexOf (':');
 337                                 string l = idx < 0 ? s : s.Substring (idx + 1);
 338                                 return idx < 0 ? new QName (l) :
 339                                         new QName (l, reader.LookupNamespace (
 340                                                 s.Substring (0, idx)));
 341                         case "decimal":
 342                                 return XmlConvert.ToDecimal (s);
 343                         case "double":
 344                                 return XmlConvert.ToDouble (s);
 345                         case "float":
 346                                 return XmlConvert.ToSingle (s);
 347                         case "byte":
 348                                 return XmlConvert.ToSByte (s);
 349                         case "short":
 350                                 return XmlConvert.ToInt16 (s);
 351                         case "int":
 352                                 return XmlConvert.ToInt32 (s);
 353                         case "long":
 354                                 return XmlConvert.ToInt64 (s);
 355                         case "unsignedByte":
 356                                 return XmlConvert.ToByte (s);
 357                         case "unsignedShort":
 358                                 return XmlConvert.ToUInt16 (s);
 359                         case "unsignedInt":
 360                                 return XmlConvert.ToUInt32 (s);
 361                         case "unsignedLong":
 362                                 return XmlConvert.ToUInt64 (s);
 363                         case "string":
 364                                 return s;
 365                         case "guid":
 366                                 return XmlConvert.ToGuid (s);
 367                         case "anyType":
 368                                 return s;
 369                         case "char":
 370                                 return (char) XmlConvert.ToUInt32 (s);
 371                         default:
 372                                 throw new Exception ("Unanticipated primitive type: " + name);
 373                         }
 374                 }
 375
 376                 List<SerializationMap> contracts = new List<SerializationMap> ();
 377
 378                 public KnownTypeCollection ()
 379                 {
 380                 }
 381
 382                 protected override void ClearItems ()
 383                 {
 384                         base.Clear ();
 385                 }
 386
 387                 protected override void InsertItem (int index, Type type)
 388                 {
 389                         if (ShouldNotRegister (type))
 390                                 return;
 391                         if (!Contains (type)) {
 392                                 TryRegister (type);
 393                                 base.InsertItem (index, type);
 394                         }
 395                 }
 396
 397                 // FIXME: it could remove other types' dependencies.
 398                 protected override void RemoveItem (int index)
 399                 {
 400                         Type t = base [index];
 401                         List<SerializationMap> l = new List<SerializationMap> ();
 402                         foreach (SerializationMap m in contracts) {
 403                                 if (m.RuntimeType == t)
 404                                         l.Add (m);
 405                         }
 406                         foreach (SerializationMap m in l) {
 407                                 contracts.Remove (m);
 408                                 base.RemoveItem (index);
 409                         }
 410                 }
 411
 412                 protected override void SetItem (int index, Type type)
 413                 {
 414                         if (ShouldNotRegister (type))
 415                                 return;
 416
 417                         // Since this collection is not assured to be ordered, it ignores the whole Set operation if the type already exists.
 418                         if (Contains (type))
 419                                 return;
 420
 421                         if (index != Count)
 422                                 RemoveItem (index);
 423                         if (TryRegister (type))
 424                                 base.InsertItem (index - 1, type);
 425                 }
 426
 427                 internal SerializationMap FindUserMap (QName qname)
 428                 {
 429                         return contracts.FirstOrDefault (c => c.XmlName == qname);
 430                 }
 431
 432                 internal Type GetSerializedType (Type type)
 433                 {
 434                         Type element = GetCollectionElementType (type);
 435                         if (element == null)
 436                                 return type;
 437                         QName name = GetQName (type);
 438                         var map = FindUserMap (name);
 439                         if (map != null)
 440                                 return map.RuntimeType;
 441                         return type;
 442                 }
 443
 444                 internal SerializationMap FindUserMap (Type type)
 445                 {
 446                         for (int i = 0; i < contracts.Count; i++)
 447                                 if (type == contracts [i].RuntimeType)
 448                                         return contracts [i];
 449                         return null;
 450                 }
 451
 452                 internal QName GetQName (Type type)
 453                 {
 454                         SerializationMap map = FindUserMap (type);
 455                         if (map != null)
 456                                 // already mapped.
 457                                 return map.XmlName;
 458                         return GetStaticQName (type);
 459                 }
 460
 461                 public static QName GetStaticQName (Type type)
 462                 {
 463                         if (IsPrimitiveNotEnum (type))
 464                                 return GetPrimitiveTypeName (type);
 465
 466                         if (type.IsEnum)
 467                                 return GetEnumQName (type);
 468
 469                         QName qname = GetContractQName (type);
 470                         if (qname != null)
 471                                 return qname;
 472
 473                         if (type.GetInterface ("System.Xml.Serialization.IXmlSerializable") != null)
 474                                 //FIXME: Reusing GetSerializableQName here, since we just
 475                                 //need name of the type..
 476                                 return GetSerializableQName (type);
 477
 478                         qname = GetCollectionContractQName (type);
 479                         if (qname != null)
 480                                 return qname;
 481
 482                         Type element = GetCollectionElementType (type);
 483                         if (element != null)
 484                                 return GetCollectionQName (element);
 485
 486                         if (GetAttribute<SerializableAttribute> (type) != null)
 487                                 return GetSerializableQName (type);
 488
 489                         // default type map - still uses GetContractQName().
 490                         return GetContractQName (type, null, null);
 491                 }
 492
 493                 internal static QName GetContractQName (Type type)
 494                 {
 495                         var a = GetAttribute<DataContractAttribute> (type);
 496                         return a == null ? null : GetContractQName (type, a.Name, a.Namespace);
 497                 }
 498
 499                 static QName GetCollectionContractQName (Type type)
 500                 {
 501                         var a = GetAttribute<CollectionDataContractAttribute> (type);
 502                         return a == null ? null : GetContractQName (type, a.Name, a.Namespace);
 503                 }
 504
 505                 static QName GetContractQName (Type type, string name, string ns)
 506                 {
 507                         if (name == null)
 508                                 name = GetDefaultName (type);
 509                         if (ns == null)
 510                                 ns = GetDefaultNamespace (type);
 511                         return new QName (name, ns);
 512                 }
 513
 514                 static QName GetEnumQName (Type type)
 515                 {
 516                         string name = null, ns = null;
 517
 518                         if (!type.IsEnum)
 519                                 return null;
 520
 521                         var dca = GetAttribute<DataContractAttribute> (type);
 522
 523                         if (dca != null) {
 524                                 ns = dca.Namespace;
 525                                 name = dca.Name;
 526                         }
 527
 528                         if (ns == null)
 529                                 ns = GetDefaultNamespace (type);
 530
 531                         if (name == null)
 532                                 name = type.Namespace == null ? type.Name : type.FullName.Substring (type.Namespace.Length + 1).Replace ('+', '.');
 533
 534                         return new QName (name, ns);
 535                 }
 536
 537                 internal static string GetDefaultName (Type type)
 538                 {
 539                         // FIXME: there could be decent ways to get
 540                         // the same result...
 541                         string name = type.Namespace == null || type.Namespace.Length == 0 ? type.Name : type.FullName.Substring (type.Namespace.Length + 1).Replace ('+', '.');
 542                         if (type.IsGenericType) {
 543                                 name = name.Substring (0, name.IndexOf ('`')) + "Of";
 544                                 foreach (var t in type.GetGenericArguments ())
 545                                         name += t.Name; // FIXME: check namespaces too
 546                         }
 547                         return name;
 548                 }
 549
 550                 internal static string GetDefaultNamespace (Type type)
 551                 {
 552                         foreach (ContractNamespaceAttribute a in type.Assembly.GetCustomAttributes (typeof (ContractNamespaceAttribute), true))
 553                                 if (a.ClrNamespace == type.Namespace)
 554                                         return a.ContractNamespace;
 555                         return DefaultClrNamespaceBase + type.Namespace;
 556                 }
 557
 558                 static QName GetCollectionQName (Type element)
 559                 {
 560                         QName eqname = GetStaticQName (element);
 561
 562                         string ns = eqname.Namespace;
 563                         if (eqname.Namespace == MSSimpleNamespace)
 564                                 //Arrays of Primitive types
 565                                 ns = MSArraysNamespace;
 566
 567                         return new QName (
 568                                 "ArrayOf" + XmlConvert.EncodeLocalName (eqname.Name),
 569                                 ns);
 570                 }
 571
 572                 static QName GetSerializableQName (Type type)
 573                 {
 574 #if !NET_2_1
 575                         // First, check XmlSchemaProviderAttribute and try GetSchema() to see if it returns a schema in the expected format.
 576                         var xpa = type.GetCustomAttribute<XmlSchemaProviderAttribute> (true);
 577                         if (xpa != null) {
 578                                 var mi = type.GetMethod (xpa.MethodName, BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static);
 579                                 if (mi != null) {
 580                                         try {
 581                                                 var xss = new XmlSchemaSet ();
 582                                                 return (XmlQualifiedName) mi.Invoke (null, new object [] {xss});
 583                                         } catch {
 584                                                 // ignore.
 585                                         }
 586                                 }
 587                         }
 588 #endif
 589
 590                         string xmlName = type.Name;
 591                         if (type.IsGenericType) {
 592                                 xmlName = xmlName.Substring (0, xmlName.IndexOf ('`')) + "Of";
 593                                 foreach (var t in type.GetGenericArguments ())
 594                                         xmlName += GetStaticQName (t).Name; // FIXME: check namespaces too
 595                         }
 596                         string xmlNamespace = GetDefaultNamespace (type);
 597                         var x = GetAttribute<XmlRootAttribute> (type);
 598                         if (x != null) {
 599                                 xmlName = x.ElementName;
 600                                 xmlNamespace = x.Namespace;
 601                         }
 602                         return new QName (XmlConvert.EncodeLocalName (xmlName), xmlNamespace);
 603                 }
 604
 605                 static bool IsPrimitiveNotEnum (Type type)
 606                 {
 607                         if (type.IsEnum)
 608                                 return false;
 609                         if (Type.GetTypeCode (type) != TypeCode.Object) // explicitly primitive
 610                                 return true;
 611                         if (type == typeof (Guid) || type == typeof (object) || type == typeof(TimeSpan) || type == typeof(byte[]) || type==typeof(Uri)) // special primitives
 612                                 return true;
 613                         // nullable
 614                         if (type.IsGenericType && type.GetGenericTypeDefinition () == typeof (Nullable<>))
 615                                 return IsPrimitiveNotEnum (type.GetGenericArguments () [0]);
 616                         return false;
 617                 }
 618
 619                 bool ShouldNotRegister (Type type)
 620                 {
 621                         return IsPrimitiveNotEnum (type);
 622                 }
 623
 624                 internal bool TryRegister (Type type)
 625                 {
 626                         // exclude predefined maps
 627                         if (ShouldNotRegister (type))
 628                                 return false;
 629
 630                         if (FindUserMap (type) != null)
 631                                 return false;
 632
 633                         if (RegisterEnum (type) != null)
 634                                 return true;
 635
 636                         if (RegisterDictionary (type) != null)
 637                                 return true;
 638
 639                         if (RegisterCollectionContract (type) != null)
 640                                 return true;
 641
 642                         if (RegisterContract (type) != null)
 643                                 return true;
 644
 645                         if (RegisterIXmlSerializable (type) != null)
 646                                 return true;
 647
 648                         if (RegisterCollection (type) != null)
 649                                 return true;
 650
 651                         if (GetAttribute<SerializableAttribute> (type) != null) {
 652                                 RegisterSerializable (type);
 653                                 return true;
 654                         }
 655
 656                         RegisterDefaultTypeMap (type);
 657                         return true;
 658                 }
 659
 660                 static Type GetCollectionElementType (Type type)
 661                 {
 662                         if (type.IsArray)
 663                                 return type.GetElementType ();
 664
 665                         Type [] ifaces = type.GetInterfaces ();
 666                         foreach (Type i in ifaces)
 667                                 if (i.IsGenericType && i.GetGenericTypeDefinition ().Equals (typeof (ICollection<>)))
 668                                         return i.GetGenericArguments () [0];
 669                         foreach (Type i in ifaces)
 670                                 if (i == typeof (IList))
 671                                         return typeof (object);
 672                         return null;
 673                 }
 674
 675                 internal static T GetAttribute<T> (ICustomAttributeProvider ap) where T : Attribute
 676                 {
 677                         object [] atts = ap.GetCustomAttributes (typeof (T), false);
 678                         return atts.Length == 0 ? null : (T) atts [0];
 679                 }
 680
 681                 private CollectionContractTypeMap RegisterCollectionContract (Type type)
 682                 {
 683                         var cdca = GetAttribute<CollectionDataContractAttribute> (type);
 684                         if (cdca == null)
 685                                 return null;
 686
 687                         Type element = GetCollectionElementType (type);
 688                         if (element == null)
 689                                 throw new InvalidOperationException (String.Format ("Type '{0}' is marked as collection contract, but it is not a collection", type));
 690
 691                         TryRegister (element); // must be registered before the name conflict check.
 692
 693                         QName qname = GetCollectionContractQName (type);
 694                         CheckStandardQName (qname);
 695                         if (FindUserMap (qname) != null)
 696                                 throw new InvalidOperationException (String.Format ("Failed to add type {0} to known type collection. There already is a registered type for XML name {1}", type, qname));
 697
 698                         var ret = new CollectionContractTypeMap (type, cdca, element, qname, this);
 699                         contracts.Add (ret);
 700                         return ret;
 701                 }
 702
 703                 private CollectionTypeMap RegisterCollection (Type type)
 704                 {
 705                         Type element = GetCollectionElementType (type);
 706                         if (element == null)
 707                                 return null;
 708
 709                         TryRegister (element);
 710
 711                         QName qname = GetCollectionQName (element);
 712
 713                         var map = FindUserMap (qname);
 714                         if (map != null) {
 715                                 var cmap = map as CollectionTypeMap;
 716                                 if (cmap == null || cmap.RuntimeType != type)
 717                                         throw new InvalidOperationException (String.Format ("Failed to add type {0} to known type collection. There already is a registered type for XML name {1}", type, qname));
 718                                 return cmap;
 719                         }
 720
 721                         CollectionTypeMap ret =
 722                                 new CollectionTypeMap (type, element, qname, this);
 723                         contracts.Add (ret);
 724                         return ret;
 725                 }
 726
 727                 static bool TypeImplementsIDictionary (Type type)
 728                 {
 729                         foreach (var iface in type.GetInterfaces ())
 730                                 if (iface == typeof (IDictionary) || (iface.IsGenericType && iface.GetGenericTypeDefinition () == typeof (IDictionary<,>)))
 731                                         return true;
 732
 733                         return false;
 734                 }
 735
 736                 // it also supports contract-based dictionary.
 737                 private DictionaryTypeMap RegisterDictionary (Type type)
 738                 {
 739                         if (!TypeImplementsIDictionary (type))
 740                                 return null;
 741
 742                         var cdca = GetAttribute<CollectionDataContractAttribute> (type);
 743
 744                         DictionaryTypeMap ret =
 745                                 new DictionaryTypeMap (type, cdca, this);
 746
 747                         if (FindUserMap (ret.XmlName) != null)
 748                                 throw new InvalidOperationException (String.Format ("Failed to add type {0} to known type collection. There already is a registered type for XML name {1}", type, ret.XmlName));
 749                         contracts.Add (ret);
 750
 751                         TryRegister (ret.KeyType);
 752                         TryRegister (ret.ValueType);
 753
 754                         return ret;
 755                 }
 756
 757                 private SerializationMap RegisterSerializable (Type type)
 758                 {
 759                         QName qname = GetSerializableQName (type);
 760
 761                         if (FindUserMap (qname) != null)
 762                                 throw new InvalidOperationException (String.Format ("There is already a registered type for XML name {0}", qname));
 763
 764                         SharedTypeMap ret = new SharedTypeMap (type, qname, this);
 765                         contracts.Add (ret);
 766                         ret.Initialize ();
 767                         return ret;
 768                 }
 769
 770                 private SerializationMap RegisterIXmlSerializable (Type type)
 771                 {
 772                         if (type.GetInterface ("System.Xml.Serialization.IXmlSerializable") == null)
 773                                 return null;
 774
 775                         QName qname = GetSerializableQName (type);
 776
 777                         if (FindUserMap (qname) != null)
 778                                 throw new InvalidOperationException (String.Format ("There is already a registered type for XML name {0}", qname));
 779
 780                         XmlSerializableMap ret = new XmlSerializableMap (type, qname, this);
 781                         contracts.Add (ret);
 782
 783                         return ret;
 784                 }
 785
 786                 void CheckStandardQName (QName qname)
 787                 {
 788                         switch (qname.Namespace) {
 789                         case XmlSchema.Namespace:
 790                         case XmlSchema.InstanceNamespace:
 791                         case MSSimpleNamespace:
 792                         case MSArraysNamespace:
 793                                 throw new InvalidOperationException (String.Format ("Namespace {0} is reserved and cannot be used for user serialization", qname.Namespace));
 794                         }
 795
 796                 }
 797
 798                 private SharedContractMap RegisterContract (Type type)
 799                 {
 800                         QName qname = GetContractQName (type);
 801                         if (qname == null)
 802                                 return null;
 803                         CheckStandardQName (qname);
 804                         if (FindUserMap (qname) != null)
 805                                 throw new InvalidOperationException (String.Format ("There is already a registered type for XML name {0}", qname));
 806
 807                         SharedContractMap ret = new SharedContractMap (type, qname, this);
 808                         contracts.Add (ret);
 809                         ret.Initialize ();
 810
 811                         if (type.BaseType != typeof (object)) {
 812                                 TryRegister (type.BaseType);
 813                                 if (!FindUserMap (type.BaseType).IsContractAllowedType)
 814                                         throw new InvalidDataContractException (String.Format ("To be serializable by data contract, type '{0}' cannot inherit from non-contract and non-Serializable type '{1}'", type, type.BaseType));
 815                         }
 816
 817                         object [] attrs = type.GetCustomAttributes (typeof (KnownTypeAttribute), true);
 818                         for (int i = 0; i < attrs.Length; i++) {
 819                                 KnownTypeAttribute kt = (KnownTypeAttribute) attrs [i];
 820                                 TryRegister (kt.Type);
 821                         }
 822
 823                         return ret;
 824                 }
 825
 826                 DefaultTypeMap RegisterDefaultTypeMap (Type type)
 827                 {
 828                         DefaultTypeMap ret = new DefaultTypeMap (type, this);
 829                         contracts.Add (ret);
 830                         ret.Initialize ();
 831                         return ret;
 832                 }
 833
 834                 private EnumMap RegisterEnum (Type type)
 835                 {
 836                         QName qname = GetEnumQName (type);
 837                         if (qname == null)
 838                                 return null;
 839
 840                         if (FindUserMap (qname) != null)
 841                                 throw new InvalidOperationException (String.Format ("There is already a registered type for XML name {0}", qname));
 842
 843                         EnumMap ret =
 844                                 new EnumMap (type, qname, this);
 845                         contracts.Add (ret);
 846                         return ret;
 847                 }
 848         }
 849 }
 850 #endif