mcs/class/System/System.Collections.Specialized/NameObjectCollectionBase.cs

   1 //
   2 // System.Collections.Specialized.NameObjectCollectionBase.cs
   3 //
   4 // Author:
   5 //   Gleb Novodran
   6 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   7 //
   8 // (C) Ximian, Inc.  http://www.ximian.com
   9 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Collections;
  33 using System.Runtime.Serialization;
  34
  35 namespace System.Collections.Specialized
  36 {
  37         [Serializable]
  38         public abstract class NameObjectCollectionBase : ICollection, IEnumerable, ISerializable, IDeserializationCallback
  39         {
  40                 private Hashtable m_ItemsContainer;
  41                 /// <summary>
  42                 /// Extends Hashtable based Items container to support storing null-key pairs
  43                 /// </summary>
  44                 private _Item m_NullKeyItem;
  45                 private ArrayList m_ItemsArray;
  46                 private IHashCodeProvider m_hashprovider;
  47                 private IComparer m_comparer;
  48                 private int m_defCapacity;
  49                 private bool m_readonly;
  50                 SerializationInfo infoCopy;
  51                 private KeysCollection keyscoll;
  52                 private IEqualityComparer equality_comparer;
  53
  54                 internal IEqualityComparer EqualityComparer {
  55                         get { return equality_comparer; }
  56                 }
  57
  58                 internal IComparer Comparer {
  59                         get {return m_comparer;}
  60                 }
  61
  62                 internal IHashCodeProvider HashCodeProvider {
  63                         get {return m_hashprovider;}
  64                 }
  65
  66                 internal class _Item
  67                 {
  68                         public string key;
  69                         public object value;
  70                         public _Item(string key, object value)
  71                         {
  72                                 this.key = key;
  73                                 this.value = value;
  74                         }
  75                 }
  76                 /// <summary>
  77                 /// Implements IEnumerable interface for KeysCollection
  78                 /// </summary>
  79                 [Serializable]
  80                 internal class _KeysEnumerator : IEnumerator
  81                 {
  82                         private NameObjectCollectionBase m_collection;
  83                         private int m_position;
  84
  85                         internal _KeysEnumerator(NameObjectCollectionBase collection)
  86                         {
  87                                 m_collection = collection;
  88                                 Reset();
  89                         }
  90                         public object Current
  91                         {
  92
  93                                 get{
  94                                         if ((m_position<m_collection.Count)||(m_position<0))
  95                                                 return m_collection.BaseGetKey(m_position);
  96                                         else
  97                                                 throw new InvalidOperationException();
  98                                 }
  99
 100                         }
 101                         public bool MoveNext()
 102                         {
 103                                 return ((++m_position) < m_collection.Count);
 104                         }
 105                         public void Reset()
 106                         {
 107                                 m_position = -1;
 108                         }
 109                 }
 110
 111                 /// <summary>
 112                 /// SDK: Represents a collection of the String keys of a collection.
 113                 /// </summary>
 114                 [Serializable]
 115                 public class KeysCollection : ICollection, IEnumerable
 116                 {
 117                         private NameObjectCollectionBase m_collection;
 118
 119                         internal KeysCollection (NameObjectCollectionBase collection)
 120                         {
 121                                 this.m_collection = collection;
 122                         }
 123
 124                         public virtual string Get( int index )
 125                         {
 126                                 return m_collection.BaseGetKey(index);
 127                         }
 128
 129                         // ICollection methods -----------------------------------
 130                         void ICollection.CopyTo (Array array, int arrayIndex)
 131                         {
 132                                 ArrayList items = m_collection.m_ItemsArray;
 133                                 if (null == array)
 134                                         throw new ArgumentNullException ("array");
 135
 136                                 if (arrayIndex < 0)
 137                                         throw new ArgumentOutOfRangeException ("arrayIndex");
 138
 139                                 if ((array.Length > 0) && (arrayIndex >= array.Length))
 140                                         throw new ArgumentException ("arrayIndex is equal to or greater than array.Length");
 141
 142                                 if (arrayIndex + items.Count > array.Length)
 143                                         throw new ArgumentException ("Not enough room from arrayIndex to end of array for this KeysCollection");
 144
 145                                 if (array != null && array.Rank > 1)
 146                                         throw new ArgumentException ("array is multidimensional");
 147
 148                                 object[] objArray = (object[])array;
 149                                 for (int i = 0; i < items.Count; i++, arrayIndex++)
 150                                         objArray [arrayIndex] = ((_Item)items [i]).key;
 151                         }
 152
 153                         bool ICollection.IsSynchronized
 154                         {
 155                                 get{
 156                                         return false;
 157                                 }
 158                         }
 159                         object ICollection.SyncRoot
 160                         {
 161                                 get{
 162                                         return m_collection;
 163                                 }
 164                         }
 165                         /// <summary>
 166                         /// Gets the number of keys in the NameObjectCollectionBase.KeysCollection
 167                         /// </summary>
 168                         public int Count
 169                         {
 170                                 get{
 171                                         return m_collection.Count;
 172                                 }
 173                         }
 174
 175                         public string this [int index] {
 176                                 get { return Get (index); }
 177                         }
 178
 179                         // IEnumerable methods --------------------------------
 180                         /// <summary>
 181                         /// SDK: Returns an enumerator that can iterate through the NameObjectCollectionBase.KeysCollection.
 182                         /// </summary>
 183                         /// <returns></returns>
 184                         public IEnumerator GetEnumerator()
 185                         {
 186                                 return new _KeysEnumerator(m_collection);
 187                         }
 188                 }
 189
 190                 //--------------- Protected Instance Constructors --------------
 191
 192                 /// <summary>
 193                 /// SDK: Initializes a new instance of the NameObjectCollectionBase class that is empty.
 194                 /// </summary>
 195                 protected NameObjectCollectionBase ()
 196                 {
 197                         m_readonly = false;
 198                         m_hashprovider = CaseInsensitiveHashCodeProvider.DefaultInvariant;
 199                         m_comparer = CaseInsensitiveComparer.DefaultInvariant;
 200                         m_defCapacity = 0;
 201                         Init();
 202                 }
 203
 204                 protected NameObjectCollectionBase( int capacity )
 205                 {
 206                         m_readonly = false;
 207                         m_hashprovider = CaseInsensitiveHashCodeProvider.DefaultInvariant;
 208                         m_comparer = CaseInsensitiveComparer.DefaultInvariant;
 209                         m_defCapacity = capacity;
 210                         Init();
 211                 }
 212
 213                 internal NameObjectCollectionBase (IEqualityComparer equalityComparer, IComparer comparer, IHashCodeProvider hcp)
 214                 {
 215                         equality_comparer = equalityComparer;
 216                         m_comparer = comparer;
 217                         m_hashprovider = hcp;
 218                         m_readonly = false;
 219                         m_defCapacity = 0;
 220                         Init ();
 221                 }
 222
 223                 protected NameObjectCollectionBase (IEqualityComparer equalityComparer) : this( (equalityComparer == null ? StringComparer.InvariantCultureIgnoreCase : equalityComparer), null, null)
 224                 {
 225                 }
 226
 227                 [Obsolete ("Use NameObjectCollectionBase(IEqualityComparer)")]
 228                 protected NameObjectCollectionBase( IHashCodeProvider hashProvider, IComparer comparer )
 229                 {
 230                         m_comparer = comparer;
 231                         m_hashprovider = hashProvider;
 232                         m_readonly = false;
 233                         m_defCapacity = 0;
 234                         Init ();
 235                 }
 236
 237                 protected NameObjectCollectionBase (SerializationInfo info, StreamingContext context)
 238                 {
 239                         infoCopy = info;
 240                 }
 241
 242                 protected NameObjectCollectionBase (int capacity, IEqualityComparer equalityComparer)
 243                 {
 244                         m_readonly = false;
 245                         equality_comparer = (equalityComparer == null ? StringComparer.InvariantCultureIgnoreCase : equalityComparer);
 246                         m_defCapacity = capacity;
 247                         Init();
 248                 }
 249
 250                 [Obsolete ("Use NameObjectCollectionBase(int,IEqualityComparer)")]
 251                 protected NameObjectCollectionBase( int capacity, IHashCodeProvider hashProvider, IComparer comparer )
 252                 {
 253                         m_readonly = false;
 254
 255                         m_hashprovider = hashProvider;
 256                         m_comparer = comparer;
 257                         m_defCapacity = capacity;
 258                         Init();
 259                 }
 260
 261                 private void Init ()
 262                 {
 263                         if (m_ItemsContainer != null) {
 264                                 m_ItemsContainer.Clear ();
 265                                 m_ItemsContainer = null;
 266                         }
 267
 268                         if (m_ItemsArray != null) {
 269                                 m_ItemsArray.Clear ();
 270                                 m_ItemsArray = null;
 271                         }
 272                         if (equality_comparer != null)
 273                                 m_ItemsContainer = new Hashtable (m_defCapacity, equality_comparer);
 274                         else
 275                                 m_ItemsContainer = new Hashtable (m_defCapacity, m_hashprovider, m_comparer);
 276                         m_ItemsArray = new ArrayList();
 277                         m_NullKeyItem = null;
 278                 }
 279
 280                 //--------------- Public Instance Properties -------------------
 281
 282                 public virtual NameObjectCollectionBase.KeysCollection Keys {
 283                         get {
 284                                 if (keyscoll == null)
 285                                         keyscoll = new KeysCollection (this);
 286                                 return keyscoll;
 287                         }
 288                 }
 289
 290                 //--------------- Public Instance Methods ----------------------
 291                 //
 292                 /// <summary>
 293                 /// SDK: Returns an enumerator that can iterate through the NameObjectCollectionBase.
 294                 ///
 295                 /// <remark>This enumerator returns the keys of the collection as strings.</remark>
 296                 /// </summary>
 297                 /// <returns></returns>
 298                 public virtual IEnumerator GetEnumerator()
 299                 {
 300                         return new _KeysEnumerator(this);
 301                 }
 302
 303                 // ISerializable
 304                 public virtual void GetObjectData (SerializationInfo info, StreamingContext context)
 305                 {
 306                         if (info == null)
 307                                 throw new ArgumentNullException ("info");
 308
 309                         int count = Count;
 310                         string [] keys = new string [count];
 311                         object [] values = new object [count];
 312                         int i = 0;
 313                         foreach (_Item item in m_ItemsArray) {
 314                                 keys [i] = item.key;
 315                                 values [i] = item.value;
 316                                 i++;
 317                         }
 318
 319                         if (equality_comparer != null) {
 320                                 info.AddValue ("KeyComparer", equality_comparer, typeof (IEqualityComparer));
 321                                 info.AddValue ("Version", 4, typeof (int));
 322                         } else {
 323                                 info.AddValue ("HashProvider", m_hashprovider, typeof (IHashCodeProvider));
 324                                 info.AddValue ("Comparer", m_comparer, typeof (IComparer));
 325                                 info.AddValue ("Version", 2, typeof (int));
 326                         }
 327                         info.AddValue("ReadOnly", m_readonly);
 328                         info.AddValue("Count", count);
 329                         info.AddValue("Keys", keys, typeof(string[]));
 330                         info.AddValue("Values", values, typeof(object[]));
 331                 }
 332
 333                 // ICollection
 334                 public virtual int Count
 335                 {
 336                         get{
 337                                 return m_ItemsArray.Count;
 338                         }
 339                 }
 340
 341                 bool ICollection.IsSynchronized
 342                 {
 343                         get { return false; }
 344                 }
 345
 346                 object ICollection.SyncRoot
 347                 {
 348                         get { return this; }
 349                 }
 350
 351                 void ICollection.CopyTo (Array array, int index)
 352                 {
 353                         ((ICollection)Keys).CopyTo (array, index);
 354                 }
 355
 356                 // IDeserializationCallback
 357                 public virtual void OnDeserialization (object sender)
 358                 {
 359                         SerializationInfo info = infoCopy;
 360
 361                         // If a subclass overrides the serialization constructor
 362                         // and inplements its own serialization process, infoCopy will
 363                         // be null and we can ignore this callback.
 364                         if (info == null)
 365                                 return;
 366
 367                         infoCopy = null;
 368                         m_hashprovider = (IHashCodeProvider) info.GetValue ("HashProvider",
 369                                                                             typeof (IHashCodeProvider));
 370                         if (m_hashprovider == null) {
 371                                 equality_comparer = (IEqualityComparer) info.GetValue ("KeyComparer", typeof (IEqualityComparer));
 372                         } else {
 373                                 m_comparer = (IComparer) info.GetValue ("Comparer", typeof (IComparer));
 374                                 if (m_comparer == null)
 375                                         throw new SerializationException ("The comparer is null");
 376                         }
 377                         m_readonly = info.GetBoolean ("ReadOnly");
 378                         string [] keys = (string []) info.GetValue ("Keys", typeof (string []));
 379                         if (keys == null)
 380                                 throw new SerializationException ("keys is null");
 381
 382                         object [] values = (object []) info.GetValue ("Values", typeof (object []));
 383                         if (values == null)
 384                                 throw new SerializationException ("values is null");
 385
 386                         Init ();
 387                         int count = keys.Length;
 388                         for (int i = 0; i < count; i++)
 389                                 BaseAdd (keys [i], values [i]);
 390                 }
 391
 392                 //--------------- Protected Instance Properties ----------------
 393                 /// <summary>
 394                 /// SDK: Gets or sets a value indicating whether the NameObjectCollectionBase instance is read-only.
 395                 /// </summary>
 396                 protected bool IsReadOnly
 397                 {
 398                         get{
 399                                 return m_readonly;
 400                         }
 401                         set{
 402                                 m_readonly=value;
 403                         }
 404                 }
 405
 406                 //--------------- Protected Instance Methods -------------------
 407                 /// <summary>
 408                 /// Adds an Item with the specified key and value into the <see cref="NameObjectCollectionBase"/>NameObjectCollectionBase instance.
 409                 /// </summary>
 410                 /// <param name="name"></param>
 411                 /// <param name="value"></param>
 412                 protected void BaseAdd( string name, object value )
 413                 {
 414                         if (this.IsReadOnly)
 415                                 throw new NotSupportedException("Collection is read-only");
 416
 417                         _Item newitem=new _Item(name, value);
 418
 419                         if (name==null){
 420                                 //todo: consider nullkey entry
 421                                 if (m_NullKeyItem==null)
 422                                         m_NullKeyItem = newitem;
 423                         }
 424                         else
 425                                 if (m_ItemsContainer[name]==null){
 426                                         m_ItemsContainer.Add(name,newitem);
 427                                 }
 428                         m_ItemsArray.Add(newitem);
 429                 }
 430
 431                 protected void BaseClear()
 432                 {
 433                         if (this.IsReadOnly)
 434                                 throw new NotSupportedException("Collection is read-only");
 435                         Init();
 436                 }
 437
 438                 /// <summary>
 439                 /// SDK: Gets the value of the entry at the specified index of the NameObjectCollectionBase instance.
 440                 /// </summary>
 441                 /// <param name="index"></param>
 442                 /// <returns></returns>
 443                 protected object BaseGet( int index )
 444                 {
 445                         return ((_Item)m_ItemsArray[index]).value;
 446                 }
 447
 448                 /// <summary>
 449                 /// SDK: Gets the value of the first entry with the specified key from the NameObjectCollectionBase instance.
 450                 /// </summary>
 451                 /// <remark>CAUTION: The BaseGet method does not distinguish between a null reference which is returned because the specified key is not found and a null reference which is returned because the value associated with the key is a null reference.</remark>
 452                 /// <param name="name"></param>
 453                 /// <returns></returns>
 454                 protected object BaseGet( string name )
 455                 {
 456                         _Item item = FindFirstMatchedItem(name);
 457                         /// CAUTION: The BaseGet method does not distinguish between a null reference which is returned because the specified key is not found and a null reference which is returned because the value associated with the key is a null reference.
 458                         if (item==null)
 459                                 return null;
 460                         else
 461                                 return item.value;
 462                 }
 463
 464                 /// <summary>
 465                 /// SDK:Returns a String array that contains all the keys in the NameObjectCollectionBase instance.
 466                 /// </summary>
 467                 /// <returns>A String array that contains all the keys in the NameObjectCollectionBase instance.</returns>
 468                 protected string[] BaseGetAllKeys()
 469                 {
 470                         int cnt = m_ItemsArray.Count;
 471                         string[] allKeys = new string[cnt];
 472                         for(int i=0; i<cnt; i++)
 473                                 allKeys[i] = BaseGetKey(i);//((_Item)m_ItemsArray[i]).key;
 474
 475                         return allKeys;
 476                 }
 477
 478                 /// <summary>
 479                 /// SDK: Returns an Object array that contains all the values in the NameObjectCollectionBase instance.
 480                 /// </summary>
 481                 /// <returns>An Object array that contains all the values in the NameObjectCollectionBase instance.</returns>
 482                 protected object[] BaseGetAllValues()
 483                 {
 484                         int cnt = m_ItemsArray.Count;
 485                         object[] allValues = new object[cnt];
 486                         for(int i=0; i<cnt; i++)
 487                                 allValues[i] = BaseGet(i);
 488
 489                         return allValues;
 490                 }
 491
 492                 protected object[] BaseGetAllValues( Type type )
 493                 {
 494                         if (type == null)
 495                                 throw new ArgumentNullException("'type' argument can't be null");
 496                         int cnt = m_ItemsArray.Count;
 497                         object[] allValues = (object[]) Array.CreateInstance (type, cnt);
 498                         for(int i=0; i<cnt; i++)
 499                                 allValues[i] = BaseGet(i);
 500
 501                         return allValues;
 502                 }
 503
 504                 protected string BaseGetKey( int index )
 505                 {
 506                         return ((_Item)m_ItemsArray[index]).key;
 507                 }
 508
 509                 /// <summary>
 510                 /// Gets a value indicating whether the NameObjectCollectionBase instance contains entries whose keys are not a null reference
 511                 /// </summary>
 512                 /// <returns>true if the NameObjectCollectionBase instance contains entries whose keys are not a null reference otherwise, false.</returns>
 513                 protected bool BaseHasKeys()
 514                 {
 515                         return (m_ItemsContainer.Count>0);
 516                 }
 517
 518                 protected void BaseRemove( string name )
 519                 {
 520                         int cnt = 0;
 521                         String key;
 522                         if (this.IsReadOnly)
 523                                 throw new NotSupportedException("Collection is read-only");
 524                         if (name!=null)
 525                         {
 526                                 m_ItemsContainer.Remove(name);
 527                         }
 528                         else {
 529                                 m_NullKeyItem = null;
 530                         }
 531
 532                         cnt = m_ItemsArray.Count;
 533                         for (int i=0 ; i< cnt; ){
 534                                 key=BaseGetKey(i);
 535                                 if (Equals (key, name)) {
 536                                         m_ItemsArray.RemoveAt(i);
 537                                         cnt--;
 538                                 }
 539                                 else
 540                                         i++;
 541                         }
 542                 }
 543
 544                 /// <summary>
 545                 ///
 546                 /// </summary>
 547                 /// <param name="index"></param>
 548                 /// <LAME>This function implemented the way Microsoft implemented it -
 549                 /// item is removed from hashtable and array without considering the case when there are two items with the same key but different values in array.
 550                 /// E.g. if
 551                 /// hashtable is [("Key1","value1")] and array contains [("Key1","value1")("Key1","value2")] then
 552                 /// after RemoveAt(1) the collection will be in following state:
 553                 /// hashtable:[]
 554                 /// array: [("Key1","value1")]
 555                 /// It's ok only then the key is uniquely assosiated with the value
 556                 /// To fix it a comparsion of objects stored under the same key in the hashtable and in the arraylist should be added
 557                 /// </LAME>>
 558                 protected void BaseRemoveAt( int index )
 559                 {
 560                         if (this.IsReadOnly)
 561                                 throw new NotSupportedException("Collection is read-only");
 562                         string key = BaseGetKey(index);
 563                         if (key!=null){
 564                                 // TODO: see LAME description above
 565                                 m_ItemsContainer.Remove(key);
 566                         }
 567                         else
 568                                 m_NullKeyItem = null;
 569                         m_ItemsArray.RemoveAt(index);
 570                 }
 571
 572                 /// <summary>
 573                 /// SDK: Sets the value of the entry at the specified index of the NameObjectCollectionBase instance.
 574                 /// </summary>
 575                 /// <param name="index"></param>
 576                 /// <param name="value"></param>
 577                 protected void BaseSet( int index, object value )
 578                 {
 579                         if (this.IsReadOnly)
 580                                 throw new NotSupportedException("Collection is read-only");
 581                         _Item item = (_Item)m_ItemsArray[index];
 582                         item.value = value;
 583                 }
 584
 585                 /// <summary>
 586                 /// Sets the value of the first entry with the specified key in the NameObjectCollectionBase instance, if found; otherwise, adds an entry with the specified key and value into the NameObjectCollectionBase instance.
 587                 /// </summary>
 588                 /// <param name="name">The String key of the entry to set. The key can be a null reference </param>
 589                 /// <param name="value">The Object that represents the new value of the entry to set. The value can be a null reference</param>
 590                 protected void BaseSet( string name, object value )
 591                 {
 592                         if (this.IsReadOnly)
 593                                 throw new NotSupportedException("Collection is read-only");
 594                         _Item item = FindFirstMatchedItem(name);
 595                         if (item!=null)
 596                                 item.value=value;
 597                         else
 598                                 BaseAdd(name, value);
 599                 }
 600
 601                 [MonoTODO]
 602                 private _Item FindFirstMatchedItem(string name)
 603                 {
 604                         if (name!=null)
 605                                 return (_Item)m_ItemsContainer[name];
 606                         else {
 607                                 //TODO: consider null key case
 608                                 return m_NullKeyItem;
 609                         }
 610                 }
 611
 612                 internal bool Equals (string s1, string s2)
 613                 {
 614                         if (m_comparer != null)
 615                                 return (m_comparer.Compare (s1, s2) == 0);
 616                         else
 617                                 return equality_comparer.Equals (s1, s2);
 618                 }
 619         }
 620 }