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authorDahlia Trimble2009-06-03 08:41:08 +0000
committerDahlia Trimble2009-06-03 08:41:08 +0000
commit9e3b592fa3636cf3d50460e303173de55bcb3920 (patch)
treeb2c39f6540fd52cc6382958f5604af1305210902
parentThanks aduffy70 for Mantis #3762: A patch to fix llGround, llGroundNormal, an... (diff)
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Thank you Imaze Rhiano for a patch that implements Cenome Memory Asset Cache (Mantis #3759)
See the files: bin/config-include/GridCommon.ini.example and bin/config-include/StandaloneCommon.ini.example to configure and enable this caching method.
Diffstat (limited to '')
-rw-r--r--CONTRIBUTORS.txt1
-rw-r--r--OpenSim/Framework/CnmMemoryCache.cs1852
-rw-r--r--OpenSim/Framework/CnmSynchronizedCache.cs746
-rw-r--r--OpenSim/Framework/ICnmCache.cs441
-rw-r--r--OpenSim/Framework/PrimeNumberHelper.cs98
-rw-r--r--OpenSim/Region/CoreModules/Asset/CenomeAssetCache.cs382
-rw-r--r--OpenSim/Region/CoreModules/Resources/CoreModulePlugin.addin.xml1
-rw-r--r--bin/config-include/GridCommon.ini.example8
-rw-r--r--bin/config-include/StandaloneCommon.ini.example8
9 files changed, 3537 insertions, 0 deletions
diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index e774812..6917c59 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -73,6 +73,7 @@ what it is today.
73* Ewe Loon 73* Ewe Loon
74* Fly-Man 74* Fly-Man
75* Flyte Xevious 75* Flyte Xevious
76* Imaze Rhiano
76* Intimidated 77* Intimidated
77* Jeremy Bongio (IBM) 78* Jeremy Bongio (IBM)
78* jhurliman 79* jhurliman
diff --git a/OpenSim/Framework/CnmMemoryCache.cs b/OpenSim/Framework/CnmMemoryCache.cs
new file mode 100644
index 0000000..6ca71ec
--- /dev/null
+++ b/OpenSim/Framework/CnmMemoryCache.cs
@@ -0,0 +1,1852 @@
1// --------------------------------------------------------------------------------------------------------------------
2// <copyright company="" file="CnmMemoryCache.cs">
3//
4// </copyright>
5// <summary>
6//
7// </summary>
8// --------------------------------------------------------------------------------------------------------------------
9
10using System;
11using System.Collections;
12using System.Collections.Generic;
13using System.Diagnostics;
14
15namespace OpenSim.Framework
16{
17 /// <summary>
18 /// Cenome memory based cache to store key/value pairs (elements) limited time and/or limited size.
19 /// </summary>
20 /// <typeparam name="TKey">
21 /// The type of keys in the cache.
22 /// </typeparam>
23 /// <typeparam name="TValue">
24 /// The type of values in the dictionary.
25 /// </typeparam>
26 /// <remarks>
27 /// <para>
28 /// Cenome memory cache stores elements to hash table generations. When new element is being added to cache, and new size would exceed
29 /// maximal allowed size or maximal amount of allowed element count, then elements in oldest generation are deleted. Last access time
30 /// is also tracked in generation level - thus it is possible that some elements are staying in cache far beyond their expiration time.
31 /// If elements in older generations are accessed through <see cref="TryGetValue"/> method, they are moved to newest generation.
32 /// </para>
33 /// </remarks>
34 public class CnmMemoryCache<TKey, TValue> : ICnmCache<TKey, TValue>
35 {
36 /// <summary>
37 /// Default maximal count.
38 /// </summary>
39 /// <seealso cref="MaxCount"/>
40 public const int DefaultMaxCount = 4096;
41
42 /// <summary>
43 /// Default maximal size.
44 /// </summary>
45 /// <remarks>
46 /// <para>
47 /// 128MB = 128 * 1024^2 = 134 217 728 bytes.
48 /// </para>
49 /// </remarks>
50 /// <seealso cref="MaxSize"/>
51 public const long DefaultMaxSize = 134217728;
52
53 /// <summary>
54 /// How many operations between time checks.
55 /// </summary>
56 private const int DefaultOperationsBetweenTimeChecks = 40;
57
58 /// <summary>
59 /// Default expiration time.
60 /// </summary>
61 /// <remarks>
62 /// <para>
63 /// 30 minutes.
64 /// </para>
65 /// </remarks>
66 public static readonly TimeSpan DefaultExpirationTime = TimeSpan.FromMinutes( 30.0 );
67
68 /// <summary>
69 /// Minimal allowed expiration time.
70 /// </summary>
71 /// <remarks>
72 /// <para>
73 /// 5 minutes.
74 /// </para>
75 /// </remarks>
76 public static readonly TimeSpan MinExpirationTime = TimeSpan.FromSeconds( 10.0 );
77
78 /// <summary>
79 /// Comparer used to compare element keys.
80 /// </summary>
81 /// <remarks>
82 /// Comparer is initialized by constructor.
83 /// </remarks>
84 /// <seealso cref="CnmMemoryCache{TKey,TValue}"/>
85 public readonly IEqualityComparer<TKey> Comparer;
86
87 /// <summary>
88 /// Expiration time.
89 /// </summary>
90 private TimeSpan m_expirationTime = DefaultExpirationTime;
91
92 /// <summary>
93 /// Generation bucket count.
94 /// </summary>
95 private int m_generationBucketCount;
96
97 /// <summary>
98 /// Generation entry count.
99 /// </summary>
100 private int m_generationElementCount;
101
102 /// <summary>
103 /// Generation max size.
104 /// </summary>
105 private long m_generationMaxSize;
106
107 /// <summary>
108 /// Maximal allowed count of elements.
109 /// </summary>
110 private int m_maxCount;
111
112 /// <summary>
113 /// Maximal allowed total size of elements.
114 /// </summary>
115 private long m_maxElementSize;
116
117 /// <summary>
118 /// Maximal size.
119 /// </summary>
120 private long m_maxSize;
121
122 /// <summary>
123 /// New generation.
124 /// </summary>
125 private IGeneration m_newGeneration;
126
127 /// <summary>
128 /// Old generation.
129 /// </summary>
130 private IGeneration m_oldGeneration;
131
132 /// <summary>
133 /// Operations between time check.
134 /// </summary>
135 private int m_operationsBetweenTimeChecks = DefaultOperationsBetweenTimeChecks;
136
137 /// <summary>
138 /// Synchronization root object, should always be private and exists always
139 /// </summary>
140 private readonly object m_syncRoot = new object();
141
142 /// <summary>
143 /// Version of cache.
144 /// </summary>
145 /// <remarks>
146 /// <para>
147 /// Updated every time when cache has been changed (element removed, expired, added, replaced).
148 /// </para>
149 /// </remarks>
150 private int m_version;
151
152 /// <summary>
153 /// Initializes a new instance of the <see cref="CnmMemoryCache{TKey,TValue}"/> class.
154 /// </summary>
155 public CnmMemoryCache()
156 : this( DefaultMaxSize )
157 {
158 }
159
160 /// <summary>
161 /// Initializes a new instance of the <see cref="CnmMemoryCache{TKey,TValue}"/> class.
162 /// </summary>
163 /// <param name="maximalSize">
164 /// Maximal cache size.
165 /// </param>
166 public CnmMemoryCache( long maximalSize )
167 : this( maximalSize, DefaultMaxCount )
168 {
169 }
170
171 /// <summary>
172 /// Initializes a new instance of the <see cref="CnmMemoryCache{TKey,TValue}"/> class.
173 /// </summary>
174 /// <param name="maximalSize">
175 /// Maximal cache size.
176 /// </param>
177 /// <param name="maximalCount">
178 /// Maximal element count.
179 /// </param>
180 public CnmMemoryCache( long maximalSize, int maximalCount )
181 : this( maximalSize, maximalCount, DefaultExpirationTime )
182 {
183 }
184
185 /// <summary>
186 /// Initializes a new instance of the <see cref="CnmMemoryCache{TKey,TValue}"/> class.
187 /// </summary>
188 /// <param name="maximalSize">
189 /// Maximal cache size.
190 /// </param>
191 /// <param name="maximalCount">
192 /// Maximal element count.
193 /// </param>
194 /// <param name="expirationTime">
195 /// Elements expiration time.
196 /// </param>
197 public CnmMemoryCache( long maximalSize, int maximalCount, TimeSpan expirationTime )
198 : this( maximalSize, maximalCount, expirationTime, EqualityComparer<TKey>.Default )
199 {
200 }
201
202 /// <summary>
203 /// Initializes a new instance of the <see cref="CnmMemoryCache{TKey,TValue}"/> class.
204 /// </summary>
205 /// <param name="maximalSize">
206 /// Maximal cache size.
207 /// </param>
208 /// <param name="maximalCount">
209 /// Maximal element count.
210 /// </param>
211 /// <param name="expirationTime">
212 /// Elements expiration time.
213 /// </param>
214 /// <param name="comparer">
215 /// Comparer used for comparing elements.
216 /// </param>
217 /// <exception cref="ArgumentNullException">
218 /// <see cref="comparer"/>is <see langword="null"/> reference.
219 /// </exception>
220 public CnmMemoryCache( long maximalSize,
221 int maximalCount,
222 TimeSpan expirationTime,
223 IEqualityComparer<TKey> comparer )
224 {
225 if( comparer == null )
226 throw new ArgumentNullException( "comparer" );
227
228 if( expirationTime < MinExpirationTime )
229 expirationTime = MinExpirationTime;
230 if( maximalCount < 8 )
231 maximalCount = 8;
232 if( maximalSize < 8 )
233 maximalSize = 8;
234 if( maximalCount > maximalSize )
235 maximalCount = (int) maximalSize;
236
237 Comparer = comparer;
238 m_expirationTime = expirationTime;
239 m_maxSize = maximalSize;
240 m_maxCount = maximalCount;
241
242 Initialize();
243 }
244
245 /// <summary>
246 /// Add element to new generation.
247 /// </summary>
248 /// <param name="bucketIndex">
249 /// The bucket index.
250 /// </param>
251 /// <param name="key">
252 /// The element's key.
253 /// </param>
254 /// <param name="value">
255 /// The element's value.
256 /// </param>
257 /// <param name="size">
258 /// The element's size.
259 /// </param>
260 protected virtual void AddToNewGeneration( int bucketIndex, TKey key, TValue value, long size )
261 {
262 // Add to newest generation
263 if( !m_newGeneration.Set( bucketIndex, key, value, size ) )
264 {
265 // Failed to add new generation
266 RecycleGenerations();
267 m_newGeneration.Set( bucketIndex, key, value, size );
268 }
269
270 m_version++;
271 }
272
273 /// <summary>
274 /// <para>
275 /// Get keys bucket index.
276 /// </para>
277 /// </summary>
278 /// <param name="key">
279 /// <para>
280 /// Key which bucket index is being retrieved.
281 /// </para>
282 /// </param>
283 /// <returns>
284 /// <para>
285 /// Bucket index.
286 /// </para>
287 /// </returns>
288 /// <remarks>
289 /// <para>
290 /// Method uses <see cref="Comparer"/> to calculate <see cref="key"/> hash code.
291 /// </para>
292 /// <para>
293 /// Bucket index is remainder when element key's hash value is divided by bucket count.
294 /// </para>
295 /// <para>
296 /// For example: key's hash is 72, bucket count is 5, element's bucket index is 72 % 5 = 2.
297 /// </para>
298 /// </remarks>
299 protected virtual int GetBucketIndex( TKey key )
300 {
301 return (Comparer.GetHashCode( key ) & 0x7FFFFFFF) % m_generationBucketCount;
302 }
303
304 /// <summary>
305 /// Purge generation from the cache.
306 /// </summary>
307 /// <param name="generation">
308 /// The generation that is purged.
309 /// </param>
310 protected virtual void PurgeGeneration( IGeneration generation )
311 {
312 generation.Clear();
313 m_version++;
314 }
315
316 /// <summary>
317 /// check expired.
318 /// </summary>
319 private void CheckExpired()
320 {
321 // Do this only one in every m_operationsBetweenTimeChecks
322 // Fetching time is using several millisecons - it is better not to do all time.
323 m_operationsBetweenTimeChecks--;
324 if( m_operationsBetweenTimeChecks <= 0 )
325 PurgeExpired();
326 }
327
328 /// <summary>
329 /// Initialize cache.
330 /// </summary>
331 private void Initialize()
332 {
333 m_version++;
334
335 m_generationMaxSize = MaxSize / 2;
336 MaxElementSize = MaxSize / 8;
337 m_generationElementCount = MaxCount / 2;
338
339 // Buckets need to be prime number to get better spread of hash values
340 m_generationBucketCount = PrimeNumberHelper.GetPrime( m_generationElementCount );
341
342 m_newGeneration = new HashGeneration( this );
343 m_oldGeneration = new HashGeneration( this );
344 m_oldGeneration.MakeOld();
345 }
346
347 /// <summary>
348 /// Recycle generations.
349 /// </summary>
350 private void RecycleGenerations()
351 {
352 // Rotate old generation to new generation, new generation to old generation
353 IGeneration temp = m_newGeneration;
354 m_newGeneration = m_oldGeneration;
355 m_newGeneration.Clear();
356 m_oldGeneration = temp;
357 m_oldGeneration.MakeOld();
358 }
359
360 #region Nested type: Enumerator
361
362 /// <summary>
363 /// Key and value pair enumerator.
364 /// </summary>
365 private class Enumerator : IEnumerator<KeyValuePair<TKey, TValue>>
366 {
367 /// <summary>
368 /// Current enumerator.
369 /// </summary>
370 private int m_currentEnumerator = -1;
371
372 /// <summary>
373 /// Enumerators to different generations.
374 /// </summary>
375 private readonly IEnumerator<KeyValuePair<TKey, TValue>>[] m_generationEnumerators =
376 new IEnumerator<KeyValuePair<TKey, TValue>>[2];
377
378 /// <summary>
379 /// Initializes a new instance of the <see cref="Enumerator"/> class.
380 /// </summary>
381 /// <param name="cache">
382 /// The cache.
383 /// </param>
384 public Enumerator( CnmMemoryCache<TKey, TValue> cache )
385 {
386 m_generationEnumerators[ 0 ] = cache.m_newGeneration.GetEnumerator();
387 m_generationEnumerators[ 1 ] = cache.m_oldGeneration.GetEnumerator();
388 }
389
390 #region IEnumerator<KeyValuePair<TKey,TValue>> Members
391
392 /// <summary>
393 /// Gets the element in the collection at the current position of the enumerator.
394 /// </summary>
395 /// <returns>
396 /// The element in the collection at the current position of the enumerator.
397 /// </returns>
398 /// <exception cref="InvalidOperationException">
399 /// The enumerator has reach end of collection or <see cref="MoveNext"/> is not called.
400 /// </exception>
401 public KeyValuePair<TKey, TValue> Current
402 {
403 get
404 {
405 if( m_currentEnumerator == -1 || m_currentEnumerator >= m_generationEnumerators.Length )
406 throw new InvalidOperationException();
407
408 return m_generationEnumerators[ m_currentEnumerator ].Current;
409 }
410 }
411
412 /// <summary>
413 /// Gets the current element in the collection.
414 /// </summary>
415 /// <returns>
416 /// The current element in the collection.
417 /// </returns>
418 /// <exception cref="T:System.InvalidOperationException">
419 /// The enumerator is positioned before the first element of the collection or after the last element.
420 /// </exception><filterpriority>2</filterpriority>
421 object IEnumerator.Current
422 {
423 get { return Current; }
424 }
425
426 /// <summary>
427 /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
428 /// </summary>
429 /// <filterpriority>2</filterpriority>
430 public void Dispose()
431 {
432 }
433
434 /// <summary>
435 /// Advances the enumerator to the next element of the collection.
436 /// </summary>
437 /// <returns>
438 /// <see langword="true"/>if the enumerator was successfully advanced to the next element; <see langword="false"/> if the enumerator has passed the end of the collection.
439 /// </returns>
440 /// <exception cref="T:System.InvalidOperationException">
441 /// The collection was modified after the enumerator was created.
442 /// </exception>
443 /// <filterpriority>2</filterpriority>
444 public bool MoveNext()
445 {
446 if( m_currentEnumerator == -1 )
447 m_currentEnumerator = 0;
448
449 while( m_currentEnumerator < m_generationEnumerators.Length )
450 {
451 if( m_generationEnumerators[ m_currentEnumerator ].MoveNext() )
452 return true;
453
454 m_currentEnumerator++;
455 }
456
457 return false;
458 }
459
460 /// <summary>
461 /// Sets the enumerator to its initial position, which is before the first element in the collection.
462 /// </summary>
463 /// <exception cref="T:System.InvalidOperationException">
464 /// The collection was modified after the enumerator was created.
465 /// </exception>
466 /// <filterpriority>2</filterpriority>
467 public void Reset()
468 {
469 foreach( IEnumerator<KeyValuePair<TKey, TValue>> enumerator in m_generationEnumerators )
470 {
471 enumerator.Reset();
472 }
473
474 m_currentEnumerator = -1;
475 }
476
477 #endregion
478 }
479
480 #endregion
481
482 #region Nested type: HashGeneration
483
484 /// <summary>
485 /// Hash generation class
486 /// </summary>
487 /// <remarks>
488 /// <para>
489 /// Current implementation is based to separated chaining with move-to-front heuristics. Hash generations have fixed
490 /// amount of buckets and it is never rehashed.
491 /// </para>
492 /// <para>
493 /// Read more about hash tables from <a href="http://en.wikipedia.org/wiki/Hash_table">Wiki article</a>.
494 /// </para>
495 /// </remarks>
496 /// <seealso href="http://en.wikipedia.org/wiki/Hash_table"/>
497 private class HashGeneration : IGeneration
498 {
499 /// <summary>
500 /// Value indicating whether generation was accessed since last time check.
501 /// </summary>
502 private bool m_accessedSinceLastTimeCheck;
503
504 /// <summary>
505 /// Index of first element's in element chain.
506 /// </summary>
507 /// <value>
508 /// -1 if there is no element in bucket; otherwise first element's index in the element chain.
509 /// </value>
510 /// <remarks>
511 /// Bucket index is remainder when element key's hash value is divided by bucket count.
512 /// For example: key's hash is 72, bucket count is 5, element's bucket index is 72 % 5 = 2.
513 /// </remarks>
514 private readonly int[] m_buckets;
515
516 /// <summary>
517 /// Cache object.
518 /// </summary>
519 private readonly CnmMemoryCache<TKey, TValue> m_cache;
520
521 /// <summary>
522 /// Generation's element array.
523 /// </summary>
524 /// <seealso cref="Element"/>
525 private readonly Element[] m_elements;
526
527 /// <summary>
528 /// Generation's expiration time.
529 /// </summary>
530 private DateTime m_expirationTime1;
531
532 /// <summary>
533 /// Index to first free element.
534 /// </summary>
535 private int m_firstFreeElement;
536
537 /// <summary>
538 /// Free element count.
539 /// </summary>
540 /// <remarks>
541 /// When generation is cleared or constructed, this is NOT set to element count.
542 /// This is only tracking elements that are removed and are currently free.
543 /// </remarks>
544 private int m_freeCount;
545
546 /// <summary>
547 /// Is this generation "new generation".
548 /// </summary>
549 private bool m_newGeneration;
550
551 /// <summary>
552 /// Next unused entry.
553 /// </summary>
554 private int m_nextUnusedElement;
555
556 /// <summary>
557 /// Size of data stored to generation.
558 /// </summary>
559 private long m_size;
560
561 /// <summary>
562 /// Initializes a new instance of the <see cref="HashGeneration"/> class.
563 /// </summary>
564 /// <param name="cache">
565 /// The cache.
566 /// </param>
567 public HashGeneration( CnmMemoryCache<TKey, TValue> cache )
568 {
569 m_cache = cache;
570 m_elements = new Element[m_cache.m_generationElementCount];
571 m_buckets = new int[m_cache.m_generationBucketCount];
572 Clear();
573 }
574
575 /// <summary>
576 /// Find element's index
577 /// </summary>
578 /// <param name="bucketIndex">
579 /// The element's bucket index.
580 /// </param>
581 /// <param name="key">
582 /// The element's key.
583 /// </param>
584 /// <param name="moveToFront">
585 /// Move element to front of elements.
586 /// </param>
587 /// <param name="previousIndex">
588 /// The previous element's index.
589 /// </param>
590 /// <returns>
591 /// Element's index, if found from the generation; -1 otherwise (if element is not found the generation).
592 /// </returns>
593 private int FindElementIndex( int bucketIndex, TKey key, bool moveToFront, out int previousIndex )
594 {
595 previousIndex = -1;
596 int elementIndex = m_buckets[ bucketIndex ];
597 while( elementIndex >= 0 )
598 {
599 if( m_cache.Comparer.Equals( key, m_elements[ elementIndex ].Key ) )
600 {
601 // Found match
602 if( moveToFront && previousIndex >= 0 )
603 {
604 // Move entry to front
605 m_elements[ previousIndex ].Next = m_elements[ elementIndex ].Next;
606 m_elements[ elementIndex ].Next = m_buckets[ bucketIndex ];
607 m_buckets[ bucketIndex ] = elementIndex;
608 previousIndex = 0;
609 }
610
611 return elementIndex;
612 }
613
614 previousIndex = elementIndex;
615 elementIndex = m_elements[ elementIndex ].Next;
616 }
617
618 return -1;
619 }
620
621 /// <summary>
622 /// Remove element front the generation.
623 /// </summary>
624 /// <param name="bucketIndex">
625 /// The bucket index.
626 /// </param>
627 /// <param name="entryIndex">
628 /// The element index.
629 /// </param>
630 /// <param name="previousIndex">
631 /// The element's previous index.
632 /// </param>
633 private void RemoveElement( int bucketIndex, int entryIndex, int previousIndex )
634 {
635 if( previousIndex >= 0 )
636 m_elements[ previousIndex ].Next = m_elements[ entryIndex ].Next;
637 else
638 m_buckets[ bucketIndex ] = m_elements[ entryIndex ].Next;
639
640 Size -= m_elements[ entryIndex ].Size;
641 m_elements[ entryIndex ].Value = default(TValue);
642 m_elements[ entryIndex ].Key = default(TKey);
643
644 // Add element to free elements list
645 m_elements[ entryIndex ].Next = m_firstFreeElement;
646 m_firstFreeElement = entryIndex;
647 m_freeCount++;
648 }
649
650 #region Nested type: Element
651
652 /// <summary>
653 /// Element that stores key, next element in chain, size and value.
654 /// </summary>
655 private struct Element
656 {
657 /// <summary>
658 /// Element's key.
659 /// </summary>
660 public TKey Key;
661
662 /// <summary>
663 /// Next element in chain.
664 /// </summary>
665 /// <remarks>
666 /// When element have value (something is stored to it), this is index of
667 /// next element with same bucket index. When element is free, this
668 /// is index of next element in free element's list.
669 /// </remarks>
670 public int Next;
671
672 /// <summary>
673 /// Size of element.
674 /// </summary>
675 /// <value>
676 /// 0 if element is free; otherwise larger than 0.
677 /// </value>
678 public long Size;
679
680 /// <summary>
681 /// Element's value.
682 /// </summary>
683 /// <remarks>
684 /// It is possible that this value is <see langword="null"/> even when element
685 /// have value - element's value is then <see langword="null"/> reference.
686 /// </remarks>
687 public TValue Value;
688
689 /// <summary>
690 /// Gets a value indicating whether element is free or have value.
691 /// </summary>
692 /// <value>
693 /// <see langword="true"/> when element is free; otherwise <see langword="false"/>.
694 /// </value>
695 public bool IsFree
696 {
697 get { return Size == 0; }
698 }
699 }
700
701 #endregion
702
703 #region Nested type: Enumerator
704
705 /// <summary>
706 /// Key value pair enumerator for <see cref="HashGeneration"/> object.
707 /// </summary>
708 private class Enumerator : IEnumerator<KeyValuePair<TKey, TValue>>
709 {
710 /// <summary>
711 /// Current element.
712 /// </summary>
713 private KeyValuePair<TKey, TValue> m_current;
714
715 /// <summary>
716 /// Current index.
717 /// </summary>
718 private int m_currentIndex;
719
720 /// <summary>
721 /// Generation that is being enumerated.
722 /// </summary>
723 private readonly HashGeneration m_generation;
724
725 /// <summary>
726 /// Cache version.
727 /// </summary>
728 /// <remarks>
729 /// When cache is change, version number is changed.
730 /// </remarks>
731 /// <seealso cref="CnmMemoryCache{TKey,TValue}.m_version"/>
732 private readonly int m_version;
733
734 /// <summary>
735 /// Initializes a new instance of the <see cref="Enumerator"/> class.
736 /// </summary>
737 /// <param name="generation">
738 /// The generation.
739 /// </param>
740 public Enumerator( HashGeneration generation )
741 {
742 m_generation = generation;
743 m_version = m_generation.m_cache.m_version;
744 }
745
746 #region IEnumerator<KeyValuePair<TKey,TValue>> Members
747
748 /// <summary>
749 /// Gets the element in the collection at the current position of the enumerator.
750 /// </summary>
751 /// <returns>
752 /// The element in the collection at the current position of the enumerator.
753 /// </returns>
754 /// <exception cref="InvalidOperationException">
755 /// The enumerator has reach end of collection or <see cref="MoveNext"/> is not called.
756 /// </exception>
757 public KeyValuePair<TKey, TValue> Current
758 {
759 get
760 {
761 if( m_currentIndex == 0 || m_currentIndex >= m_generation.Count )
762 throw new InvalidOperationException();
763
764 return m_current;
765 }
766 }
767
768 /// <summary>
769 /// Gets the current element in the collection.
770 /// </summary>
771 /// <returns>
772 /// The current element in the collection.
773 /// </returns>
774 /// <exception cref="InvalidOperationException">
775 /// The enumerator is positioned before the first element of the collection or after the last element.
776 /// </exception><filterpriority>2</filterpriority>
777 object IEnumerator.Current
778 {
779 get { return Current; }
780 }
781
782 /// <summary>
783 /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
784 /// </summary>
785 /// <filterpriority>2</filterpriority>
786 public void Dispose()
787 {
788 }
789
790 /// <summary>
791 /// Advances the enumerator to the next element of the collection.
792 /// </summary>
793 /// <returns>
794 /// true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.
795 /// </returns>
796 /// <exception cref="InvalidOperationException">
797 /// The collection was modified after the enumerator was created.
798 /// </exception>
799 public bool MoveNext()
800 {
801 if( m_version != m_generation.m_cache.m_version )
802 throw new InvalidOperationException();
803
804 while( m_currentIndex < m_generation.Count )
805 {
806 if( m_generation.m_elements[ m_currentIndex ].IsFree )
807 {
808 m_currentIndex++;
809 continue;
810 }
811
812 m_current = new KeyValuePair<TKey, TValue>( m_generation.m_elements[ m_currentIndex ].Key,
813 m_generation.m_elements[ m_currentIndex ].Value );
814 m_currentIndex++;
815 return true;
816 }
817
818 m_current = new KeyValuePair<TKey, TValue>();
819 return false;
820 }
821
822 /// <summary>
823 /// Sets the enumerator to its initial position, which is before the first element in the collection.
824 /// </summary>
825 /// <exception cref="InvalidOperationException">
826 /// The collection was modified after the enumerator was created.
827 /// </exception>
828 /// <filterpriority>2</filterpriority>
829 public void Reset()
830 {
831 if( m_version != m_generation.m_cache.m_version )
832 throw new InvalidOperationException();
833
834 m_currentIndex = 0;
835 }
836
837 #endregion
838 }
839
840 #endregion
841
842 #region IGeneration Members
843
844 /// <summary>
845 /// Gets or sets a value indicating whether generation was accessed since last time check.
846 /// </summary>
847 public bool AccessedSinceLastTimeCheck
848 {
849 get { return m_accessedSinceLastTimeCheck; }
850
851 set { m_accessedSinceLastTimeCheck = value; }
852 }
853
854 /// <summary>
855 /// Gets element count in generation.
856 /// </summary>
857 public int Count
858 {
859 get { return m_nextUnusedElement - m_freeCount; }
860 }
861
862 /// <summary>
863 /// Gets or sets generation's expiration time.
864 /// </summary>
865 public DateTime ExpirationTime
866 {
867 get { return m_expirationTime1; }
868
869 set { m_expirationTime1 = value; }
870 }
871
872 /// <summary>
873 /// Gets or sets size of data stored to generation.
874 /// </summary>
875 public long Size
876 {
877 get { return m_size; }
878
879 private set { m_size = value; }
880 }
881
882 /// <summary>
883 /// Clear all elements from the generation and make generation new again.
884 /// </summary>
885 /// <remarks>
886 /// When generation is new, it is allowed to add new elements to it and
887 /// <see cref="IGeneration.TryGetValue"/>doesn't remove elements from it.
888 /// </remarks>
889 /// <seealso cref="IGeneration.MakeOld"/>
890 public void Clear()
891 {
892 for( int i = m_buckets.Length - 1 ; i >= 0 ; i-- )
893 {
894 m_buckets[ i ] = -1;
895 }
896
897 Array.Clear( m_elements, 0, m_elements.Length );
898 Size = 0;
899 m_firstFreeElement = -1;
900 m_freeCount = 0;
901 m_nextUnusedElement = 0;
902 m_newGeneration = true;
903 ExpirationTime = DateTime.MaxValue;
904 }
905
906 /// <summary>
907 /// Determines whether the <see cref="IGeneration"/> contains an element with the specific key.
908 /// </summary>
909 /// <param name="bucketIndex">
910 /// The bucket index for the <see cref="key"/> to locate in <see cref="IGeneration"/>.
911 /// </param>
912 /// <param name="key">
913 /// The key to locate in the <see cref="IGeneration"/>.
914 /// </param>
915 /// <returns>
916 /// <see langword="true"/>if the <see cref="IGeneration"/> contains an element with the <see cref="key"/>;
917 /// otherwise <see langword="false"/>.
918 /// </returns>
919 public bool Contains( int bucketIndex, TKey key )
920 {
921 int previousIndex;
922 if( FindElementIndex( bucketIndex, key, true, out previousIndex ) == -1 )
923 return false;
924
925 AccessedSinceLastTimeCheck = true;
926 return true;
927 }
928
929 /// <summary>
930 /// Returns an enumerator that iterates through the elements stored <see cref="HashGeneration"/>.
931 /// </summary>
932 /// <returns>
933 /// A <see cref="IEnumerator"/> that can be used to iterate through the <see cref="HashGeneration"/>.
934 /// </returns>
935 /// <filterpriority>1</filterpriority>
936 public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
937 {
938 return new Enumerator( this );
939 }
940
941 /// <summary>
942 /// Make from generation old generation.
943 /// </summary>
944 /// <remarks>
945 /// When generation is old, <see cref="IGeneration.TryGetValue"/> hit removes element from the generation.
946 /// </remarks>
947 /// <seealso cref="IGeneration.Clear"/>
948 public void MakeOld()
949 {
950 m_newGeneration = false;
951 }
952
953 /// <summary>
954 /// Remove element associated with the key from the generation.
955 /// </summary>
956 /// <param name="bucketIndex">
957 /// The element's bucket index.
958 /// </param>
959 /// <param name="key">
960 /// The element's key.
961 /// </param>
962 /// <returns>
963 /// <see langword="true"/>, if remove was successful; otherwise <see langword="false"/>.
964 /// </returns>
965 public bool Remove( int bucketIndex, TKey key )
966 {
967 int previousIndex;
968 int entryIndex = FindElementIndex( bucketIndex, key, false, out previousIndex );
969 if( entryIndex != -1 )
970 {
971 RemoveElement( bucketIndex, entryIndex, previousIndex );
972 AccessedSinceLastTimeCheck = true;
973 return true;
974 }
975
976 return false;
977 }
978
979 /// <summary>
980 /// Set or add element to generation.
981 /// </summary>
982 /// <param name="bucketIndex">
983 /// The element's bucket index.
984 /// </param>
985 /// <param name="key">
986 /// The element's key.
987 /// </param>
988 /// <param name="value">
989 /// The element's value.
990 /// </param>
991 /// <param name="size">
992 /// The element's size.
993 /// </param>
994 /// <returns>
995 /// <see langword="true"/>, if setting or adding was successful; otherwise <see langword="false"/>.
996 /// </returns>
997 /// <remarks>
998 /// <para>
999 /// If element was already existing in generation and new element size fits to collection limits,
1000 /// then it's value is replaced with new one and size information is updated. If element didn't
1001 /// exists in generation before, then generation must have empty space for a new element and
1002 /// size must fit generation's limits, before element is added to generation.
1003 /// </para>
1004 /// </remarks>
1005 public bool Set( int bucketIndex, TKey key, TValue value, long size )
1006 {
1007 Debug.Assert( m_newGeneration, "It is possible to insert new elements only to newest generation." );
1008 Debug.Assert( size > 0, "New element size should be more than 0." );
1009
1010 int previousIndex;
1011 int elementIndex = FindElementIndex( bucketIndex, key, true, out previousIndex );
1012 if( elementIndex == -1 )
1013 {
1014 // New key
1015 if( Size + size > m_cache.m_generationMaxSize ||
1016 (m_nextUnusedElement == m_cache.m_generationElementCount && m_freeCount == 0) )
1017 {
1018 // Generation is full
1019 return false;
1020 }
1021
1022 // Increase size of generation
1023 Size += size;
1024
1025 // Get first free entry and update free entry list
1026 if( m_firstFreeElement != -1 )
1027 {
1028 // There was entry that was removed
1029 elementIndex = m_firstFreeElement;
1030 m_firstFreeElement = m_elements[ elementIndex ].Next;
1031 m_freeCount--;
1032 }
1033 else
1034 {
1035 // No entries removed so far - just take a last one
1036 elementIndex = m_nextUnusedElement;
1037 m_nextUnusedElement++;
1038 }
1039
1040 Debug.Assert( m_elements[ elementIndex ].IsFree, "Allocated element is not free." );
1041
1042 // Move new entry to front
1043 m_elements[ elementIndex ].Next = m_buckets[ bucketIndex ];
1044 m_buckets[ bucketIndex ] = elementIndex;
1045
1046 // Set key and update count
1047 m_elements[ elementIndex ].Key = key;
1048 }
1049 else
1050 {
1051 // Existing key
1052 if( Size - m_elements[ elementIndex ].Size + size > m_cache.m_generationMaxSize )
1053 {
1054 // Generation is full
1055 // Remove existing element, because generation is going to be recycled to
1056 // old generation and element is stored to new generation
1057 RemoveElement( bucketIndex, elementIndex, previousIndex );
1058 return false;
1059 }
1060
1061 // Update generation's size
1062 Size = Size - m_elements[ elementIndex ].Size + size;
1063 }
1064
1065 // Finally set value and size
1066 m_elements[ elementIndex ].Value = value;
1067 m_elements[ elementIndex ].Size = size;
1068
1069 // Success - key was inserterted to generation
1070 AccessedSinceLastTimeCheck = true;
1071 return true;
1072 }
1073
1074 /// <summary>
1075 /// Try to get element associated with key.
1076 /// </summary>
1077 /// <param name="bucketIndex">
1078 /// The element's bucket index.
1079 /// </param>
1080 /// <param name="key">
1081 /// The element's key.
1082 /// </param>
1083 /// <param name="value">
1084 /// The element's value.
1085 /// </param>
1086 /// <param name="size">
1087 /// The element's size.
1088 /// </param>
1089 /// <returns>
1090 /// <see langword="true"/>, if element was successful retrieved; otherwise <see langword="false"/>.
1091 /// </returns>
1092 /// <remarks>
1093 /// <para>
1094 /// If element is not found from generation then <paramref name="value"/> and <paramref name="size"/>
1095 /// are set to default value (default(TValue) and 0).
1096 /// </para>
1097 /// </remarks>
1098 public bool TryGetValue( int bucketIndex, TKey key, out TValue value, out long size )
1099 {
1100 // Find entry index,
1101 int previousIndex;
1102 int elementIndex = FindElementIndex( bucketIndex, key, m_newGeneration, out previousIndex );
1103 if( elementIndex == -1 )
1104 {
1105 value = default(TValue);
1106 size = 0;
1107 return false;
1108 }
1109
1110 value = m_elements[ elementIndex ].Value;
1111 size = m_elements[ elementIndex ].Size;
1112
1113 if( !m_newGeneration )
1114 {
1115 // Old generation - remove element, because it is moved to new generation
1116 RemoveElement( bucketIndex, elementIndex, previousIndex );
1117 }
1118
1119 AccessedSinceLastTimeCheck = true;
1120 return true;
1121 }
1122
1123 /// <summary>
1124 /// Returns an enumerator that iterates through a collection.
1125 /// </summary>
1126 /// <returns>
1127 /// An <see cref="T:System.Collections.IEnumerator"/> object that can be used to iterate through the collection.
1128 /// </returns>
1129 /// <filterpriority>2</filterpriority>
1130 IEnumerator IEnumerable.GetEnumerator()
1131 {
1132 return GetEnumerator();
1133 }
1134
1135 #endregion
1136 }
1137
1138 #endregion
1139
1140 #region Nested type: IGeneration
1141
1142 /// <summary>
1143 /// Cache element generation interface
1144 /// </summary>
1145 /// <remarks>
1146 /// <para>
1147 /// Generation can hold limited count of elements and limited size of data.
1148 /// </para>
1149 /// <para>
1150 /// There are two kind generations: "new generation" and "old generation(s)". All new elements
1151 /// are added to "new generation".
1152 /// </para>
1153 /// </remarks>
1154 protected interface IGeneration : IEnumerable<KeyValuePair<TKey, TValue>>
1155 {
1156 /// <summary>
1157 /// Gets or sets a value indicating whether generation was accessed since last time check.
1158 /// </summary>
1159 bool AccessedSinceLastTimeCheck { get; set; }
1160
1161 /// <summary>
1162 /// Gets element count in generation.
1163 /// </summary>
1164 int Count { get; }
1165
1166 /// <summary>
1167 /// Gets or sets generation's expiration time.
1168 /// </summary>
1169 DateTime ExpirationTime { get; set; }
1170
1171 /// <summary>
1172 /// Gets size of data stored to generation.
1173 /// </summary>
1174 long Size { get; }
1175
1176 /// <summary>
1177 /// Clear all elements from the generation and make generation new again.
1178 /// </summary>
1179 /// <remarks>
1180 /// When generation is new, it is allowed to add new elements to it and
1181 /// <see cref="TryGetValue"/>doesn't remove elements from it.
1182 /// </remarks>
1183 /// <seealso cref="MakeOld"/>
1184 void Clear();
1185
1186 /// <summary>
1187 /// Determines whether the <see cref="IGeneration"/> contains an element with the specific key.
1188 /// </summary>
1189 /// <param name="bucketIndex">
1190 /// The bucket index for the <see cref="key"/> to locate in <see cref="IGeneration"/>.
1191 /// </param>
1192 /// <param name="key">
1193 /// The key to locate in the <see cref="IGeneration"/>.
1194 /// </param>
1195 /// <returns>
1196 /// <see langword="true"/>if the <see cref="IGeneration"/> contains an element with the <see cref="key"/>;
1197 /// otherwise <see langword="false"/>.
1198 /// </returns>
1199 bool Contains( int bucketIndex, TKey key );
1200
1201 /// <summary>
1202 /// Make from generation old generation.
1203 /// </summary>
1204 /// <remarks>
1205 /// When generation is old, <see cref="TryGetValue"/> hit removes element from the generation.
1206 /// </remarks>
1207 /// <seealso cref="Clear"/>
1208 void MakeOld();
1209
1210 /// <summary>
1211 /// Remove element associated with the key from the generation.
1212 /// </summary>
1213 /// <param name="bucketIndex">
1214 /// The element's bucket index.
1215 /// </param>
1216 /// <param name="key">
1217 /// The element's key.
1218 /// </param>
1219 /// <returns>
1220 /// <see langword="true"/>, if remove was successful; otherwise <see langword="false"/>.
1221 /// </returns>
1222 bool Remove( int bucketIndex, TKey key );
1223
1224 /// <summary>
1225 /// Set or add element to generation.
1226 /// </summary>
1227 /// <param name="bucketIndex">
1228 /// The element's bucket index.
1229 /// </param>
1230 /// <param name="key">
1231 /// The element's key.
1232 /// </param>
1233 /// <param name="value">
1234 /// The element's value.
1235 /// </param>
1236 /// <param name="size">
1237 /// The element's size.
1238 /// </param>
1239 /// <returns>
1240 /// <see langword="true"/>, if setting or adding was successful; otherwise <see langword="false"/>.
1241 /// </returns>
1242 /// <remarks>
1243 /// <para>
1244 /// If element was already existing in generation and new element size fits to collection limits,
1245 /// then it's value is replaced with new one and size information is updated. If element didn't
1246 /// exists in generation before, then generation must have empty space for a new element and
1247 /// size must fit generation's limits, before element is added to generation.
1248 /// </para>
1249 /// </remarks>
1250 bool Set( int bucketIndex, TKey key, TValue value, long size );
1251
1252 /// <summary>
1253 /// Try to get element associated with key.
1254 /// </summary>
1255 /// <param name="bucketIndex">
1256 /// The element's bucket index.
1257 /// </param>
1258 /// <param name="key">
1259 /// The element's key.
1260 /// </param>
1261 /// <param name="value">
1262 /// The element's value.
1263 /// </param>
1264 /// <param name="size">
1265 /// The element's size.
1266 /// </param>
1267 /// <returns>
1268 /// <see langword="true"/>, if element was successful retrieved; otherwise <see langword="false"/>.
1269 /// </returns>
1270 /// <remarks>
1271 /// <para>
1272 /// If element is not found from generation then <paramref name="value"/> and <paramref name="size"/>
1273 /// are set to default value (default(TValue) and 0).
1274 /// </para>
1275 /// </remarks>
1276 bool TryGetValue( int bucketIndex, TKey key, out TValue value, out long size );
1277 }
1278
1279 #endregion
1280
1281 #region ICnmCache<TKey,TValue> Members
1282
1283 /// <summary>
1284 /// Gets current count of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
1285 /// </summary>
1286 /// <remarks>
1287 /// <para>
1288 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
1289 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1290 /// </para>
1291 /// </remarks>
1292 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
1293 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1294 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1295 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
1296 public int Count
1297 {
1298 get { return m_newGeneration.Count + m_oldGeneration.Count; }
1299 }
1300
1301 /// <summary>
1302 /// Gets or sets elements expiration time.
1303 /// </summary>
1304 /// <value>
1305 /// Elements expiration time.
1306 /// </value>
1307 /// <remarks>
1308 /// <para>
1309 /// When element has been stored in <see cref="ICnmCache{TKey,TValue}"/> longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
1310 /// and it is not accessed through <see cref="ICnmCache{TKey,TValue}.TryGetValue"/> method or element's value is
1311 /// not replaced by <see cref="ICnmCache{TKey,TValue}.Set"/> method, then it is automatically removed from the
1312 /// <see cref="ICnmCache{TKey,TValue}"/>.
1313 /// </para>
1314 /// <para>
1315 /// It is possible that <see cref="ICnmCache{TKey,TValue}"/> implementation removes element before it's expiration time,
1316 /// because total size or count of elements stored to cache is larger than <see cref="ICnmCache{TKey,TValue}.MaxSize"/> or <see cref="ICnmCache{TKey,TValue}.MaxCount"/>.
1317 /// </para>
1318 /// <para>
1319 /// It is also possible that element stays in cache longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>.
1320 /// </para>
1321 /// <para>
1322 /// Calling <see cref="ICnmCache{TKey,TValue}.PurgeExpired"/> try to remove all elements that are expired.
1323 /// </para>
1324 /// <para>
1325 /// To disable time limit in cache, set <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> to <see cref="DateTime.MaxValue"/>.
1326 /// </para>
1327 /// </remarks>
1328 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
1329 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1330 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1331 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1332 /// <seealso cref="ICnmCache{TKey,TValue}.Count"/>
1333 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
1334 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
1335 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
1336 public TimeSpan ExpirationTime
1337 {
1338 get { return m_expirationTime; }
1339
1340 set
1341 {
1342 if( value < MinExpirationTime )
1343 value = MinExpirationTime;
1344
1345 if( m_expirationTime == value )
1346 return;
1347
1348 m_newGeneration.ExpirationTime = (m_newGeneration.ExpirationTime - m_expirationTime) + value;
1349 m_oldGeneration.ExpirationTime = (m_oldGeneration.ExpirationTime - m_expirationTime) + value;
1350 m_expirationTime = value;
1351
1352 PurgeExpired();
1353 }
1354 }
1355
1356 /// <summary>
1357 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting count of elements.
1358 /// </summary>
1359 /// <value>
1360 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> count of elements is limited;
1361 /// otherwise, <see langword="false"/>.
1362 /// </value>
1363 /// <remarks>
1364 /// <para>
1365 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
1366 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1367 /// </para>
1368 /// </remarks>
1369 /// <seealso cref="ICnmCache{TKey,TValue}.Count"/>
1370 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
1371 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1372 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
1373 public bool IsCountLimited
1374 {
1375 get { return true; }
1376 }
1377
1378 /// <summary>
1379 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting size of elements.
1380 /// </summary>
1381 /// <value>
1382 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> total size of elements is limited;
1383 /// otherwise, <see langword="false"/>.
1384 /// </value>
1385 /// <remarks>
1386 /// <para>
1387 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
1388 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1389 /// </para>
1390 /// </remarks>
1391 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
1392 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
1393 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
1394 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1395 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
1396 public bool IsSizeLimited
1397 {
1398 get { return true; }
1399 }
1400
1401 /// <summary>
1402 /// Gets a value indicating whether or not access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe).
1403 /// </summary>
1404 /// <value>
1405 /// <see langword="true"/> if access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe);
1406 /// otherwise, <see langword="false"/>.
1407 /// </value>
1408 /// <remarks>
1409 /// <para>
1410 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/> object, use
1411 /// <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> in <see cref="CnmSynchronizedCache{TKey,TValue}"/> class
1412 /// to retrieve synchronized wrapper for <see cref="ICnmCache{TKey,TValue}"/> object.
1413 /// </para>
1414 /// </remarks>
1415 /// <seealso cref="ICnmCache{TKey,TValue}.SyncRoot"/>
1416 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
1417 public bool IsSynchronized
1418 {
1419 get { return false; }
1420 }
1421
1422 /// <summary>
1423 /// Gets a value indicating whether elements stored to <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time.
1424 /// </summary>
1425 /// <value>
1426 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> has a fixed total size of elements;
1427 /// otherwise, <see langword="false"/>.
1428 /// </value>
1429 /// <remarks>
1430 /// If <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time and element is not accessed through <see cref="ICnmCache{TKey,TValue}.Set"/>
1431 /// or <see cref="ICnmCache{TKey,TValue}.TryGetValue"/> methods in <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> , then element is automatically removed from
1432 /// the cache. Depending on implementation of the <see cref="ICnmCache{TKey,TValue}"/>, some of the elements may
1433 /// stay longer in cache.
1434 /// </remarks>
1435 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
1436 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1437 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1438 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1439 public bool IsTimeLimited
1440 {
1441 get { return ExpirationTime != TimeSpan.MaxValue; }
1442 }
1443
1444 /// <summary>
1445 /// Gets or sets maximal allowed count of elements that can be stored to <see cref="ICnmCache{TKey,TValue}"/>.
1446 /// </summary>
1447 /// <value>
1448 /// <see cref="int.MaxValue"/>, if <see cref="ICnmCache{TKey,TValue}"/> is not limited by count of elements;
1449 /// otherwise maximal allowed count of elements.
1450 /// </value>
1451 /// <remarks>
1452 /// <para>
1453 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
1454 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1455 /// </para>
1456 /// </remarks>
1457 public int MaxCount
1458 {
1459 get { return m_maxCount; }
1460
1461 set
1462 {
1463 if( value < 8 )
1464 value = 8;
1465 if( m_maxCount == value )
1466 return;
1467
1468 m_maxCount = value;
1469 Initialize();
1470 }
1471 }
1472
1473 /// <summary>
1474 /// <para>Gets maximal allowed element size.</para>
1475 /// </summary>
1476 /// <value>
1477 /// Maximal allowed element size.
1478 /// </value>
1479 /// <remarks>
1480 /// <para>
1481 /// If element's size is larger than <see cref="ICnmCache{TKey,TValue}.MaxElementSize"/>, then element is
1482 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>.
1483 /// </para>
1484 /// </remarks>
1485 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1486 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1487 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
1488 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
1489 public long MaxElementSize
1490 {
1491 get { return m_maxElementSize; }
1492
1493 private set { m_maxElementSize = value; }
1494 }
1495
1496 /// <summary>
1497 /// Gets or sets maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
1498 /// </summary>
1499 /// <value>
1500 /// Maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
1501 /// </value>
1502 /// <remarks>
1503 /// <para>
1504 /// Normally size is total bytes used by elements in the cache. But it can be any other suitable unit of measure.
1505 /// </para>
1506 /// <para>
1507 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
1508 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1509 /// </para>
1510 /// </remarks>
1511 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
1512 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1513 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
1514 public long MaxSize
1515 {
1516 get { return m_maxSize; }
1517
1518 set
1519 {
1520 if( value < 8 )
1521 value = 8;
1522 if( m_maxSize == value )
1523 return;
1524
1525 m_maxSize = value;
1526 Initialize();
1527 }
1528 }
1529
1530 /// <summary>
1531 /// Gets total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
1532 /// </summary>
1533 /// <value>
1534 /// Total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
1535 /// </value>
1536 /// <remarks>
1537 /// <para>
1538 /// Normally bytes, but can be any suitable unit of measure.
1539 /// </para>
1540 /// <para>
1541 /// Element's size is given when element is added or replaced by <see cref="ICnmCache{TKey,TValue}.Set"/> method.
1542 /// </para>
1543 /// <para>
1544 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
1545 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
1546 /// </para>
1547 /// </remarks>
1548 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
1549 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1550 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
1551 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1552 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
1553 public long Size
1554 {
1555 get { return m_newGeneration.Size + m_oldGeneration.Size; }
1556 }
1557
1558 /// <summary>
1559 /// Gets an object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
1560 /// </summary>
1561 /// <value>
1562 /// An object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
1563 /// </value>
1564 /// <remarks>
1565 /// <para>
1566 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/>, use <see cref="CnmSynchronizedCache{TKey,TValue}"/>
1567 /// method <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> to retrieve synchronized wrapper interface to
1568 /// <see cref="ICnmCache{TKey,TValue}"/>.
1569 /// </para>
1570 /// </remarks>
1571 /// <seealso cref="ICnmCache{TKey,TValue}.IsSynchronized"/>
1572 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
1573 public object SyncRoot
1574 {
1575 get { return m_syncRoot; }
1576 }
1577
1578 /// <summary>
1579 /// Removes all elements from the <see cref="ICnmCache{TKey,TValue}"/>.
1580 /// </summary>
1581 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1582 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
1583 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
1584 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
1585 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1586 public void Clear()
1587 {
1588 m_newGeneration.Clear();
1589 m_oldGeneration.Clear();
1590 m_oldGeneration.MakeOld();
1591 m_version++;
1592 }
1593
1594 /// <summary>
1595 /// Returns an enumerator that iterates through the elements stored to <see cref="CnmMemoryCache{TKey,TValue}"/>.
1596 /// </summary>
1597 /// <returns>
1598 /// A <see cref="IEnumerator{T}"/> that can be used to iterate through the collection.
1599 /// </returns>
1600 /// <filterpriority>1</filterpriority>
1601 public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
1602 {
1603 return new Enumerator( this );
1604 }
1605
1606 /// <summary>
1607 /// Purge expired elements from the <see cref="ICnmCache{TKey,TValue}"/>.
1608 /// </summary>
1609 /// <remarks>
1610 /// <para>
1611 /// Element becomes expired when last access time to it has been longer time than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>.
1612 /// </para>
1613 /// <para>
1614 /// Depending on <see cref="ICnmCache{TKey,TValue}"/> implementation, some of expired elements
1615 /// may stay longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> in the cache.
1616 /// </para>
1617 /// </remarks>
1618 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
1619 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
1620 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1621 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
1622 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
1623 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
1624 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
1625 public void PurgeExpired()
1626 {
1627 m_operationsBetweenTimeChecks = DefaultOperationsBetweenTimeChecks;
1628
1629 if( !IsTimeLimited )
1630 return;
1631
1632 DateTime now = DateTime.Now;
1633 if( m_newGeneration.AccessedSinceLastTimeCheck )
1634 {
1635 // New generation has been accessed since last check
1636 // Update it's expiration time.
1637 m_newGeneration.ExpirationTime = now + ExpirationTime;
1638 m_newGeneration.AccessedSinceLastTimeCheck = false;
1639 }
1640 else if( m_newGeneration.ExpirationTime < now )
1641 {
1642 // New generation has been expired.
1643 // --> also old generation must be expired.
1644 PurgeGeneration( m_newGeneration );
1645 PurgeGeneration( m_oldGeneration );
1646 return;
1647 }
1648
1649 if( m_oldGeneration.ExpirationTime < now )
1650 PurgeGeneration( m_oldGeneration );
1651 }
1652
1653 /// <summary>
1654 /// Removes element associated with <paramref name="key"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
1655 /// </summary>
1656 /// <param name="key">
1657 /// The key that is associated with element to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
1658 /// </param>
1659 /// <exception cref="ArgumentNullException">
1660 /// <paramref name="key"/>is <see langword="null"/>.
1661 /// </exception>
1662 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1663 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
1664 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
1665 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
1666 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1667 public void Remove( TKey key )
1668 {
1669 if( key == null )
1670 throw new ArgumentNullException( "key" );
1671
1672 int bucketIndex = GetBucketIndex( key );
1673 if( !m_newGeneration.Remove( bucketIndex, key ) )
1674 {
1675 if( !m_oldGeneration.Remove( bucketIndex, key ) )
1676 {
1677 CheckExpired();
1678 return;
1679 }
1680 }
1681
1682 CheckExpired();
1683 m_version++;
1684 }
1685
1686 /// <summary>
1687 /// Removes elements that are associated with one of <paramref name="keys"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
1688 /// </summary>
1689 /// <param name="keys">
1690 /// The keys that are associated with elements to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
1691 /// </param>
1692 /// <exception cref="ArgumentNullException">
1693 /// <paramref name="keys"/>is <see langword="null"/>.
1694 /// </exception>
1695 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1696 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
1697 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
1698 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
1699 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1700 public void RemoveRange( IEnumerable<TKey> keys )
1701 {
1702 if( keys == null )
1703 throw new ArgumentNullException( "keys" );
1704
1705 foreach( TKey key in keys )
1706 {
1707 if( key == null )
1708 continue;
1709
1710 int bucketIndex = GetBucketIndex( key );
1711 if( !m_newGeneration.Remove( bucketIndex, key ) )
1712 m_oldGeneration.Remove( bucketIndex, key );
1713 }
1714
1715 CheckExpired();
1716 m_version++;
1717 }
1718
1719 /// <summary>
1720 /// Add or replace an element with the provided <paramref name="key"/>, <paramref name="value"/> and <paramref name="size"/> to
1721 /// <see cref="ICnmCache{TKey,TValue}"/>.
1722 /// </summary>
1723 /// <param name="key">
1724 /// The object used as the key of the element. Can't be <see langword="null"/> reference.
1725 /// </param>
1726 /// <param name="value">
1727 /// The object used as the value of the element to add or replace. <see langword="null"/> is allowed.
1728 /// </param>
1729 /// <param name="size">
1730 /// The element's size. Normally bytes, but can be any suitable unit of measure.
1731 /// </param>
1732 /// <returns>
1733 /// <see langword="true"/>if element has been added successfully to the <see cref="ICnmCache{TKey,TValue}"/>;
1734 /// otherwise <see langword="false"/>.
1735 /// </returns>
1736 /// <exception cref="ArgumentNullException">
1737 /// <paramref name="key"/>is <see langword="null"/>.
1738 /// </exception>
1739 /// <exception cref="ArgumentOutOfRangeException">
1740 /// The element's <paramref name="size"/> is less than 0.
1741 /// </exception>
1742 /// <remarks>
1743 /// <para>
1744 /// If element's <paramref name="size"/> is larger than <see cref="ICnmCache{TKey,TValue}.MaxElementSize"/>, then element is
1745 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>, however - possible older element is
1746 /// removed from the <see cref="ICnmCache{TKey,TValue}"/>.
1747 /// </para>
1748 /// <para>
1749 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
1750 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
1751 /// </para>
1752 /// <para>
1753 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
1754 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
1755 /// </para>
1756 /// </remarks>
1757 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
1758 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
1759 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
1760 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
1761 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
1762 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
1763 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1764 public bool Set( TKey key, TValue value, long size )
1765 {
1766 if( key == null )
1767 throw new ArgumentNullException( "key" );
1768
1769 if( size < 0 )
1770 throw new ArgumentOutOfRangeException( "size", size, "Value's size can't be less than 0." );
1771
1772 if( size > MaxElementSize )
1773 {
1774 // Entry size is too big to fit cache - ignore it
1775 Remove( key );
1776 return false;
1777 }
1778
1779 if( size == 0 )
1780 size = 1;
1781
1782 int bucketIndex = GetBucketIndex( key );
1783 m_oldGeneration.Remove( bucketIndex, key );
1784 AddToNewGeneration( bucketIndex, key, value, size );
1785 CheckExpired();
1786
1787 return true;
1788 }
1789
1790 /// <summary>
1791 /// Gets the <paramref name="value"/> associated with the specified <paramref name="key"/>.
1792 /// </summary>
1793 /// <returns>
1794 /// <see langword="true"/>if the <see cref="ICnmCache{TKey,TValue}"/> contains an element with
1795 /// the specified key; otherwise, <see langword="false"/>.
1796 /// </returns>
1797 /// <param name="key">
1798 /// The key whose <paramref name="value"/> to get.
1799 /// </param>
1800 /// <param name="value">
1801 /// When this method returns, the value associated with the specified <paramref name="key"/>,
1802 /// if the <paramref name="key"/> is found; otherwise, the
1803 /// default value for the type of the <paramref name="value"/> parameter. This parameter is passed uninitialized.
1804 /// </param>
1805 /// <exception cref="ArgumentNullException">
1806 /// <paramref name="key"/>is <see langword="null"/>.
1807 /// </exception>
1808 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
1809 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
1810 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
1811 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
1812 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
1813 public bool TryGetValue( TKey key, out TValue value )
1814 {
1815 if( key == null )
1816 throw new ArgumentNullException( "key" );
1817
1818 int bucketIndex = GetBucketIndex( key );
1819 long size;
1820 if( m_newGeneration.TryGetValue( bucketIndex, key, out value, out size ) )
1821 {
1822 CheckExpired();
1823 return true;
1824 }
1825
1826 if( m_oldGeneration.TryGetValue( bucketIndex, key, out value, out size ) )
1827 {
1828 // Move element to new generation
1829 AddToNewGeneration( bucketIndex, key, value, size );
1830 CheckExpired();
1831 return true;
1832 }
1833
1834 CheckExpired();
1835 return false;
1836 }
1837
1838 /// <summary>
1839 /// Returns an enumerator that iterates through a collection.
1840 /// </summary>
1841 /// <returns>
1842 /// An <see cref="T:System.Collections.IEnumerator"/> object that can be used to iterate through the collection.
1843 /// </returns>
1844 /// <filterpriority>2</filterpriority>
1845 IEnumerator IEnumerable.GetEnumerator()
1846 {
1847 return GetEnumerator();
1848 }
1849
1850 #endregion
1851 }
1852}
diff --git a/OpenSim/Framework/CnmSynchronizedCache.cs b/OpenSim/Framework/CnmSynchronizedCache.cs
new file mode 100644
index 0000000..418a095
--- /dev/null
+++ b/OpenSim/Framework/CnmSynchronizedCache.cs
@@ -0,0 +1,746 @@
1/*
2 * Copyright (c) Contributors, http://opensimulator.org/
3 * See CONTRIBUTORS.TXT for a full list of copyright holders.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of the OpenSimulator Project nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27using System;
28using System.Collections;
29using System.Collections.Generic;
30using System.Threading;
31
32namespace OpenSim.Framework
33{
34 /// <summary>
35 /// Synchronized Cenome cache wrapper.
36 /// </summary>
37 /// <typeparam name="TKey">
38 /// The type of keys in the cache.
39 /// </typeparam>
40 /// <typeparam name="TValue">
41 /// The type of values in the cache.
42 /// </typeparam>
43 /// <remarks>
44 /// <para>
45 /// Enumerator will block other threads, until enumerator's <see cref="IDisposable.Dispose"/> method is called.
46 /// "foreach" statement is automatically calling it.
47 /// </para>
48 /// </remarks>
49 public class CnmSynchronizedCache<TKey, TValue> : ICnmCache<TKey, TValue>
50 {
51 /// <summary>
52 /// The cache object.
53 /// </summary>
54 private readonly ICnmCache<TKey, TValue> m_cache;
55
56 /// <summary>
57 /// Synchronization root.
58 /// </summary>
59 private readonly object m_syncRoot;
60
61 /// <summary>
62 /// Initializes a new instance of the <see cref="CnmSynchronizedCache{TKey,TValue}"/> class.
63 /// Initializes a new instance of the <see cref="CnmSynchronizedCache{TKey,TValue}"/> class.
64 /// </summary>
65 /// <param name="cache">
66 /// The cache.
67 /// </param>
68 private CnmSynchronizedCache( ICnmCache<TKey, TValue> cache )
69 {
70 m_cache = cache;
71 m_syncRoot = m_cache.SyncRoot;
72 }
73
74 /// <summary>
75 /// Returns a <see cref="ICnmCache{TKey,TValue}"/> wrapper that is synchronized (thread safe).
76 /// </summary>
77 /// <param name="cache">
78 /// The <see cref="ICnmCache{TKey,TValue}"/> to synchronize.
79 /// </param>
80 /// <returns>
81 /// A <see cref="ICnmCache{TKey,TValue}"/> wrapper that is synchronized (thread safe).
82 /// </returns>
83 /// <exception cref="ArgumentNullException">
84 /// <paramref name="cache"/>is null.
85 /// </exception>
86 public static ICnmCache<TKey, TValue> Synchronized( ICnmCache<TKey, TValue> cache )
87 {
88 if( cache == null )
89 throw new ArgumentNullException( "cache" );
90 return cache.IsSynchronized ? cache : new CnmSynchronizedCache<TKey, TValue>( cache );
91 }
92
93 #region Nested type: SynchronizedEnumerator
94
95 /// <summary>
96 /// Synchronized enumerator.
97 /// </summary>
98 private class SynchronizedEnumerator : IEnumerator<KeyValuePair<TKey, TValue>>
99 {
100 /// <summary>
101 /// Enumerator that is being synchronized.
102 /// </summary>
103 private readonly IEnumerator<KeyValuePair<TKey, TValue>> m_enumerator;
104
105 /// <summary>
106 /// Synchronization root.
107 /// </summary>
108 private object m_syncRoot;
109
110 /// <summary>
111 /// Initializes a new instance of the <see cref="SynchronizedEnumerator"/> class.
112 /// </summary>
113 /// <param name="enumerator">
114 /// The enumerator that is being synchronized.
115 /// </param>
116 /// <param name="syncRoot">
117 /// The sync root.
118 /// </param>
119 public SynchronizedEnumerator( IEnumerator<KeyValuePair<TKey, TValue>> enumerator, object syncRoot )
120 {
121 m_syncRoot = syncRoot;
122 m_enumerator = enumerator;
123 Monitor.Enter( m_syncRoot );
124 }
125
126 /// <summary>
127 /// Finalizes an instance of the <see cref="SynchronizedEnumerator"/> class.
128 /// </summary>
129 ~SynchronizedEnumerator()
130 {
131 Dispose();
132 }
133
134 #region IEnumerator<KeyValuePair<TKey,TValue>> Members
135
136 /// <summary>
137 /// Gets the element in the collection at the current position of the enumerator.
138 /// </summary>
139 /// <returns>
140 /// The element in the collection at the current position of the enumerator.
141 /// </returns>
142 /// <exception cref="InvalidOperationException">
143 /// The enumerator has reach end of collection or <see cref="MoveNext"/> is not called.
144 /// </exception>
145 public KeyValuePair<TKey, TValue> Current
146 {
147 get { return m_enumerator.Current; }
148 }
149
150 /// <summary>
151 /// Gets the current element in the collection.
152 /// </summary>
153 /// <returns>
154 /// The current element in the collection.
155 /// </returns>
156 /// <exception cref="InvalidOperationException">
157 /// The enumerator is positioned before the first element of the collection or after the last element.
158 /// </exception><filterpriority>2</filterpriority>
159 object IEnumerator.Current
160 {
161 get { return Current; }
162 }
163
164 /// <summary>
165 /// Releases synchronization lock.
166 /// </summary>
167 public void Dispose()
168 {
169 if( m_syncRoot != null )
170 {
171 Monitor.Exit( m_syncRoot );
172 m_syncRoot = null;
173 }
174
175 m_enumerator.Dispose();
176 GC.SuppressFinalize( this );
177 }
178
179 /// <summary>
180 /// Advances the enumerator to the next element of the collection.
181 /// </summary>
182 /// <returns>
183 /// true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.
184 /// </returns>
185 /// <exception cref="InvalidOperationException">
186 /// The collection was modified after the enumerator was created.
187 /// </exception>
188 public bool MoveNext()
189 {
190 return m_enumerator.MoveNext();
191 }
192
193 /// <summary>
194 /// Sets the enumerator to its initial position, which is before the first element in the collection.
195 /// </summary>
196 /// <exception cref="InvalidOperationException">
197 /// The collection was modified after the enumerator was created.
198 /// </exception>
199 public void Reset()
200 {
201 m_enumerator.Reset();
202 }
203
204 #endregion
205 }
206
207 #endregion
208
209 #region ICnmCache<TKey,TValue> Members
210
211 /// <summary>
212 /// Gets current count of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
213 /// </summary>
214 /// <remarks>
215 /// <para>
216 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
217 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
218 /// </para>
219 /// </remarks>
220 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
221 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
222 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
223 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
224 public int Count
225 {
226 get
227 {
228 lock( m_syncRoot )
229 {
230 return m_cache.Count;
231 }
232 }
233 }
234
235 /// <summary>
236 /// Gets or sets elements expiration time.
237 /// </summary>
238 /// <value>
239 /// Elements expiration time.
240 /// </value>
241 /// <remarks>
242 /// <para>
243 /// When element has been stored in <see cref="ICnmCache{TKey,TValue}"/> longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
244 /// and it is not accessed through <see cref="ICnmCache{TKey,TValue}.TryGetValue"/> method or element's value is
245 /// not replaced by <see cref="ICnmCache{TKey,TValue}.Set"/> method, then it is automatically removed from the
246 /// <see cref="ICnmCache{TKey,TValue}"/>.
247 /// </para>
248 /// <para>
249 /// It is possible that <see cref="ICnmCache{TKey,TValue}"/> implementation removes element before it's expiration time,
250 /// because total size or count of elements stored to cache is larger than <see cref="ICnmCache{TKey,TValue}.MaxSize"/> or <see cref="ICnmCache{TKey,TValue}.MaxCount"/>.
251 /// </para>
252 /// <para>
253 /// It is also possible that element stays in cache longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>.
254 /// </para>
255 /// <para>
256 /// Calling <see cref="ICnmCache{TKey,TValue}.PurgeExpired"/> try to remove all elements that are expired.
257 /// </para>
258 /// <para>
259 /// To disable time limit in cache, set <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> to <see cref="DateTime.MaxValue"/>.
260 /// </para>
261 /// </remarks>
262 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
263 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
264 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
265 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
266 /// <seealso cref="ICnmCache{TKey,TValue}.Count"/>
267 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
268 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
269 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
270 public TimeSpan ExpirationTime
271 {
272 get
273 {
274 lock( m_syncRoot )
275 {
276 return m_cache.ExpirationTime;
277 }
278 }
279
280 set
281 {
282 lock( m_syncRoot )
283 {
284 m_cache.ExpirationTime = value;
285 }
286 }
287 }
288
289 /// <summary>
290 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting count of elements.
291 /// </summary>
292 /// <value>
293 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> count of elements is limited;
294 /// otherwise, <see langword="false"/>.
295 /// </value>
296 /// <remarks>
297 /// <para>
298 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
299 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
300 /// </para>
301 /// </remarks>
302 /// <seealso cref="ICnmCache{TKey,TValue}.Count"/>
303 /// <seealso cref="ICnmCache{TKey,TValue}.MaxCount"/>
304 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
305 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
306 public bool IsCountLimited
307 {
308 get
309 {
310 lock( m_syncRoot )
311 {
312 return m_cache.IsCountLimited;
313 }
314 }
315 }
316
317 /// <summary>
318 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting size of elements.
319 /// </summary>
320 /// <value>
321 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> total size of elements is limited;
322 /// otherwise, <see langword="false"/>.
323 /// </value>
324 /// <remarks>
325 /// <para>
326 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
327 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
328 /// </para>
329 /// </remarks>
330 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
331 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
332 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
333 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
334 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
335 public bool IsSizeLimited
336 {
337 get
338 {
339 lock( m_syncRoot )
340 {
341 return m_cache.IsSizeLimited;
342 }
343 }
344 }
345
346 /// <summary>
347 /// Gets a value indicating whether or not access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe).
348 /// </summary>
349 /// <value>
350 /// <see langword="true"/> if access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe);
351 /// otherwise, <see langword="false"/>.
352 /// </value>
353 /// <remarks>
354 /// <para>
355 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/> object, use
356 /// <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> in <see cref="CnmSynchronizedCache{TKey,TValue}"/> class
357 /// to retrieve synchronized wrapper for <see cref="ICnmCache{TKey,TValue}"/> object.
358 /// </para>
359 /// </remarks>
360 /// <seealso cref="ICnmCache{TKey,TValue}.SyncRoot"/>
361 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
362 public bool IsSynchronized
363 {
364 get { return true; }
365 }
366
367 /// <summary>
368 /// Gets a value indicating whether elements stored to <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time.
369 /// </summary>
370 /// <value>
371 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> has a fixed total size of elements;
372 /// otherwise, <see langword="false"/>.
373 /// </value>
374 /// <remarks>
375 /// If <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time and element is not accessed through <see cref="ICnmCache{TKey,TValue}.Set"/>
376 /// or <see cref="ICnmCache{TKey,TValue}.TryGetValue"/> methods in <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> , then element is automatically removed from
377 /// the cache. Depending on implementation of the <see cref="ICnmCache{TKey,TValue}"/>, some of the elements may
378 /// stay longer in cache.
379 /// </remarks>
380 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
381 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
382 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
383 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
384 public bool IsTimeLimited
385 {
386 get
387 {
388 lock( m_syncRoot )
389 {
390 return m_cache.IsTimeLimited;
391 }
392 }
393 }
394
395 /// <summary>
396 /// Gets or sets maximal allowed count of elements that can be stored to <see cref="ICnmCache{TKey,TValue}"/>.
397 /// </summary>
398 /// <value>
399 /// <see cref="int.MaxValue"/>, if <see cref="ICnmCache{TKey,TValue}"/> is not limited by count of elements;
400 /// otherwise maximal allowed count of elements.
401 /// </value>
402 /// <remarks>
403 /// <para>
404 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
405 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
406 /// </para>
407 /// </remarks>
408 public int MaxCount
409 {
410 get
411 {
412 lock( m_syncRoot )
413 {
414 return m_cache.MaxCount;
415 }
416 }
417
418 set
419 {
420 lock( m_syncRoot )
421 {
422 m_cache.MaxCount = value;
423 }
424 }
425 }
426
427 /// <summary>
428 /// <para>Gets maximal allowed element size.</para>
429 /// </summary>
430 /// <value>
431 /// Maximal allowed element size.
432 /// </value>
433 /// <remarks>
434 /// <para>
435 /// If element's size is larger than <see cref="ICnmCache{TKey,TValue}.MaxElementSize"/>, then element is
436 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>.
437 /// </para>
438 /// </remarks>
439 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
440 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
441 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
442 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
443 public long MaxElementSize
444 {
445 get
446 {
447 lock( m_syncRoot )
448 {
449 return m_cache.MaxElementSize;
450 }
451 }
452 }
453
454 /// <summary>
455 /// Gets or sets maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
456 /// </summary>
457 /// <value>
458 /// Maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
459 /// </value>
460 /// <remarks>
461 /// <para>
462 /// Normally size is total bytes used by elements in the cache. But it can be any other suitable unit of measure.
463 /// </para>
464 /// <para>
465 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
466 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
467 /// </para>
468 /// </remarks>
469 /// <exception cref="ArgumentOutOfRangeException">value is less than 0.</exception>
470 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
471 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
472 /// <seealso cref="ICnmCache{TKey,TValue}.Size"/>
473 public long MaxSize
474 {
475 get
476 {
477 lock( m_syncRoot )
478 {
479 return m_cache.MaxSize;
480 }
481 }
482
483 set
484 {
485 lock( m_syncRoot )
486 {
487 m_cache.MaxSize = value;
488 }
489 }
490 }
491
492 /// <summary>
493 /// Gets total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
494 /// </summary>
495 /// <value>
496 /// Total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
497 /// </value>
498 /// <remarks>
499 /// <para>
500 /// Normally bytes, but can be any suitable unit of measure.
501 /// </para>
502 /// <para>
503 /// Element's size is given when element is added or replaced by <see cref="ICnmCache{TKey,TValue}.Set"/> method.
504 /// </para>
505 /// <para>
506 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
507 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
508 /// </para>
509 /// </remarks>
510 /// <seealso cref="ICnmCache{TKey,TValue}.MaxElementSize"/>
511 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
512 /// <seealso cref="ICnmCache{TKey,TValue}.MaxSize"/>
513 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
514 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
515 public long Size
516 {
517 get
518 {
519 lock( m_syncRoot )
520 {
521 return m_cache.Size;
522 }
523 }
524 }
525
526 /// <summary>
527 /// Gets an object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
528 /// </summary>
529 /// <value>
530 /// An object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
531 /// </value>
532 /// <remarks>
533 /// <para>
534 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/>, use <see cref="CnmSynchronizedCache{TKey,TValue}"/>
535 /// method <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> to retrieve synchronized wrapper interface to
536 /// <see cref="ICnmCache{TKey,TValue}"/>.
537 /// </para>
538 /// </remarks>
539 /// <seealso cref="ICnmCache{TKey,TValue}.IsSynchronized"/>
540 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
541 public object SyncRoot
542 {
543 get { return m_syncRoot; }
544 }
545
546 /// <summary>
547 /// Removes all elements from the <see cref="ICnmCache{TKey,TValue}"/>.
548 /// </summary>
549 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
550 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
551 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
552 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
553 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
554 public void Clear()
555 {
556 lock( m_syncRoot )
557 {
558 m_cache.Clear();
559 }
560 }
561
562 /// <summary>
563 /// Returns an enumerator that iterates through the elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
564 /// </summary>
565 /// <returns>
566 /// A <see cref="IEnumerator{T}"/> that can be used to iterate through the collection.
567 /// </returns>
568 /// <filterpriority>1</filterpriority>
569 public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
570 {
571 lock( m_syncRoot )
572 {
573 return new SynchronizedEnumerator( m_cache.GetEnumerator(), m_syncRoot );
574 }
575 }
576
577 /// <summary>
578 /// Purge expired elements from the <see cref="ICnmCache{TKey,TValue}"/>.
579 /// </summary>
580 /// <remarks>
581 /// <para>
582 /// Element becomes expired when last access time to it has been longer time than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/>.
583 /// </para>
584 /// <para>
585 /// Depending on <see cref="ICnmCache{TKey,TValue}"/> implementation, some of expired elements
586 /// may stay longer than <see cref="ICnmCache{TKey,TValue}.ExpirationTime"/> in the cache.
587 /// </para>
588 /// </remarks>
589 /// <seealso cref="ICnmCache{TKey,TValue}.IsTimeLimited"/>
590 /// <seealso cref="ICnmCache{TKey,TValue}.ExpirationTime"/>
591 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
592 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
593 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
594 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
595 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
596 public void PurgeExpired()
597 {
598 lock( m_syncRoot )
599 {
600 m_cache.PurgeExpired();
601 }
602 }
603
604 /// <summary>
605 /// Removes element associated with <paramref name="key"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
606 /// </summary>
607 /// <param name="key">
608 /// The key that is associated with element to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
609 /// </param>
610 /// <exception cref="ArgumentNullException">
611 /// <paramref name="key"/>is <see langword="null"/>.
612 /// </exception>
613 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
614 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
615 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
616 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
617 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
618 public void Remove( TKey key )
619 {
620 lock( m_syncRoot )
621 {
622 m_cache.Remove( key );
623 }
624 }
625
626 /// <summary>
627 /// Removes elements that are associated with one of <paramref name="keys"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
628 /// </summary>
629 /// <param name="keys">
630 /// The keys that are associated with elements to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
631 /// </param>
632 /// <exception cref="ArgumentNullException">
633 /// <paramref name="keys"/>is <see langword="null"/>.
634 /// </exception>
635 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
636 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
637 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
638 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
639 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
640 public void RemoveRange( IEnumerable<TKey> keys )
641 {
642 lock( m_syncRoot )
643 {
644 m_cache.RemoveRange( keys );
645 }
646 }
647
648 /// <summary>
649 /// Add or replace an element with the provided <paramref name="key"/>, <paramref name="value"/> and <paramref name="size"/> to
650 /// <see cref="ICnmCache{TKey,TValue}"/>.
651 /// </summary>
652 /// <param name="key">
653 /// The object used as the key of the element. Can't be <see langword="null"/> reference.
654 /// </param>
655 /// <param name="value">
656 /// The object used as the value of the element to add or replace. <see langword="null"/> is allowed.
657 /// </param>
658 /// <param name="size">
659 /// The element's size. Normally bytes, but can be any suitable unit of measure.
660 /// </param>
661 /// <returns>
662 /// <see langword="true"/>if element has been added successfully to the <see cref="ICnmCache{TKey,TValue}"/>;
663 /// otherwise <see langword="false"/>.
664 /// </returns>
665 /// <exception cref="ArgumentNullException">
666 /// <paramref name="key"/>is <see langword="null"/>.
667 /// </exception>
668 /// <exception cref="ArgumentOutOfRangeException">
669 /// The element's <paramref name="size"/> is less than 0.
670 /// </exception>
671 /// <remarks>
672 /// <para>
673 /// If element's <paramref name="size"/> is larger than <see cref="ICnmCache{TKey,TValue}.MaxElementSize"/>, then element is
674 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>, however - possible older element is
675 /// removed from the <see cref="ICnmCache{TKey,TValue}"/>.
676 /// </para>
677 /// <para>
678 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
679 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
680 /// </para>
681 /// <para>
682 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
683 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
684 /// </para>
685 /// </remarks>
686 /// <seealso cref="ICnmCache{TKey,TValue}.IsSizeLimited"/>
687 /// <seealso cref="ICnmCache{TKey,TValue}.IsCountLimited"/>
688 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
689 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
690 /// <seealso cref="ICnmCache{TKey,TValue}.TryGetValue"/>
691 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
692 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
693 public bool Set( TKey key, TValue value, long size )
694 {
695 lock( m_syncRoot )
696 {
697 return m_cache.Set( key, value, size );
698 }
699 }
700
701 /// <summary>
702 /// Gets the <paramref name="value"/> associated with the specified <paramref name="key"/>.
703 /// </summary>
704 /// <returns>
705 /// <see langword="true"/>if the <see cref="ICnmCache{TKey,TValue}"/> contains an element with
706 /// the specified key; otherwise, <see langword="false"/>.
707 /// </returns>
708 /// <param name="key">
709 /// The key whose <paramref name="value"/> to get.
710 /// </param>
711 /// <param name="value">
712 /// When this method returns, the value associated with the specified <paramref name="key"/>,
713 /// if the <paramref name="key"/> is found; otherwise, the
714 /// default value for the type of the <paramref name="value"/> parameter. This parameter is passed uninitialized.
715 /// </param>
716 /// <exception cref="ArgumentNullException">
717 /// <paramref name="key"/>is <see langword="null"/>.
718 /// </exception>
719 /// <seealso cref="ICnmCache{TKey,TValue}.Set"/>
720 /// <seealso cref="ICnmCache{TKey,TValue}.Remove"/>
721 /// <seealso cref="ICnmCache{TKey,TValue}.RemoveRange"/>
722 /// <seealso cref="ICnmCache{TKey,TValue}.Clear"/>
723 /// <seealso cref="ICnmCache{TKey,TValue}.PurgeExpired"/>
724 public bool TryGetValue( TKey key, out TValue value )
725 {
726 lock( m_syncRoot )
727 {
728 return m_cache.TryGetValue( key, out value );
729 }
730 }
731
732 /// <summary>
733 /// Returns an enumerator that iterates through the elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
734 /// </summary>
735 /// <returns>
736 /// A <see cref="IEnumerator"/> that can be used to iterate through the collection.
737 /// </returns>
738 /// <filterpriority>1</filterpriority>
739 IEnumerator IEnumerable.GetEnumerator()
740 {
741 return GetEnumerator();
742 }
743
744 #endregion
745 }
746}
diff --git a/OpenSim/Framework/ICnmCache.cs b/OpenSim/Framework/ICnmCache.cs
new file mode 100644
index 0000000..cba8a7f
--- /dev/null
+++ b/OpenSim/Framework/ICnmCache.cs
@@ -0,0 +1,441 @@
1/*
2 * Copyright (c) Contributors, http://opensimulator.org/
3 * See CONTRIBUTORS.TXT for a full list of copyright holders.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of the OpenSimulator Project nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28using System;
29using System.Collections.Generic;
30
31namespace OpenSim.Framework
32{
33 /// <summary>
34 /// Represent generic cache to store key/value pairs (elements) limited by time, size and count of elements.
35 /// </summary>
36 /// <typeparam name="TKey">
37 /// The type of keys in the cache.
38 /// </typeparam>
39 /// <typeparam name="TValue">
40 /// The type of values in the cache.
41 /// </typeparam>
42 /// <remarks>
43 /// <para>
44 /// Cache store limitations:
45 /// </para>
46 /// <list type="table">
47 /// <listheader>
48 /// <term>Limitation</term>
49 /// <description>Description</description>
50 /// </listheader>
51 /// <item>
52 /// <term>Time</term>
53 /// <description>
54 /// Element that is not accessed through <see cref="TryGetValue"/> or <see cref="Set"/> in last <see cref="ExpirationTime"/> are
55 /// removed from the cache automatically. Depending on implementation of the cache some of elements may stay longer in cache.
56 /// <see cref="IsTimeLimited"/> returns <see langword="true"/>, if cache is limited by time.
57 /// </description>
58 /// </item>
59 /// <item>
60 /// <term>Count</term>
61 /// <description>
62 /// When adding an new element to cache that already have <see cref="MaxCount"/> of elements, cache will remove less recently
63 /// used element(s) from the cache, until element fits to cache.
64 /// <see cref="IsCountLimited"/> returns <see langword="true"/>, if cache is limiting element count.
65 /// </description>
66 /// </item>
67 /// <item>
68 /// <term>Size</term>
69 /// <description>
70 /// <description>
71 /// When adding an new element to cache that already have <see cref="MaxSize"/> of elements, cache will remove less recently
72 /// used element(s) from the cache, until element fits to cache.
73 /// <see cref="IsSizeLimited"/> returns <see langword="true"/>, if cache is limiting total size of elements.
74 /// Normally size is bytes used by element in the cache. But it can be any other suitable unit of measure.
75 /// </description>
76 /// </description>
77 /// </item>
78 /// </list>
79 /// </remarks>
80 public interface ICnmCache<TKey, TValue> : IEnumerable<KeyValuePair<TKey, TValue>>
81 {
82 /// <summary>
83 /// Gets current count of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
84 /// </summary>
85 /// <remarks>
86 /// <para>
87 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
88 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
89 /// </para>
90 /// </remarks>
91 /// <seealso cref="MaxCount"/>
92 /// <seealso cref="IsCountLimited"/>
93 /// <seealso cref="IsSizeLimited"/>
94 /// <seealso cref="IsTimeLimited"/>
95 int Count { get; }
96
97 /// <summary>
98 /// Gets or sets elements expiration time.
99 /// </summary>
100 /// <value>
101 /// Elements expiration time.
102 /// </value>
103 /// <remarks>
104 /// <para>
105 /// When element has been stored in <see cref="ICnmCache{TKey,TValue}"/> longer than <see cref="ExpirationTime"/>
106 /// and it is not accessed through <see cref="TryGetValue"/> method or element's value is
107 /// not replaced by <see cref="Set"/> method, then it is automatically removed from the
108 /// <see cref="ICnmCache{TKey,TValue}"/>.
109 /// </para>
110 /// <para>
111 /// It is possible that <see cref="ICnmCache{TKey,TValue}"/> implementation removes element before it's expiration time,
112 /// because total size or count of elements stored to cache is larger than <see cref="MaxSize"/> or <see cref="MaxCount"/>.
113 /// </para>
114 /// <para>
115 /// It is also possible that element stays in cache longer than <see cref="ExpirationTime"/>.
116 /// </para>
117 /// <para>
118 /// Calling <see cref="PurgeExpired"/> try to remove all elements that are expired.
119 /// </para>
120 /// <para>
121 /// To disable time limit in cache, set <see cref="ExpirationTime"/> to <see cref="DateTime.MaxValue"/>.
122 /// </para>
123 /// </remarks>
124 /// <seealso cref="IsTimeLimited"/>
125 /// <seealso cref="IsCountLimited"/>
126 /// <seealso cref="IsSizeLimited"/>
127 /// <seealso cref="PurgeExpired"/>
128 /// <seealso cref="Count"/>
129 /// <seealso cref="MaxCount"/>
130 /// <seealso cref="MaxSize"/>
131 /// <seealso cref="Size"/>
132 TimeSpan ExpirationTime { get; set; }
133
134 /// <summary>
135 /// Gets a value indicating whether or not access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe).
136 /// </summary>
137 /// <value>
138 /// <see langword="true"/> if access to the <see cref="ICnmCache{TKey,TValue}"/> is synchronized (thread safe);
139 /// otherwise, <see langword="false"/>.
140 /// </value>
141 /// <remarks>
142 /// <para>
143 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/> object, use
144 /// <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> in <see cref="CnmSynchronizedCache{TKey,TValue}"/> class
145 /// to retrieve synchronized wrapper for <see cref="ICnmCache{TKey,TValue}"/> object.
146 /// </para>
147 /// </remarks>
148 /// <seealso cref="SyncRoot"/>
149 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
150 bool IsSynchronized { get; }
151
152 /// <summary>
153 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting count of elements.
154 /// </summary>
155 /// <value>
156 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> count of elements is limited;
157 /// otherwise, <see langword="false"/>.
158 /// </value>
159 /// <remarks>
160 /// <para>
161 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
162 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
163 /// </para>
164 /// </remarks>
165 /// <seealso cref="Count"/>
166 /// <seealso cref="MaxCount"/>
167 /// <seealso cref="IsSizeLimited"/>
168 /// <seealso cref="IsTimeLimited"/>
169 bool IsCountLimited { get; }
170
171 /// <summary>
172 /// Gets a value indicating whether <see cref="ICnmCache{TKey,TValue}"/> is limiting size of elements.
173 /// </summary>
174 /// <value>
175 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> total size of elements is limited;
176 /// otherwise, <see langword="false"/>.
177 /// </value>
178 /// <remarks>
179 /// <para>
180 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
181 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
182 /// </para>
183 /// </remarks>
184 /// <seealso cref="MaxElementSize"/>
185 /// <seealso cref="Size"/>
186 /// <seealso cref="MaxSize"/>
187 /// <seealso cref="IsCountLimited"/>
188 /// <seealso cref="IsTimeLimited"/>
189 bool IsSizeLimited { get; }
190
191 /// <summary>
192 /// Gets a value indicating whether elements stored to <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time.
193 /// </summary>
194 /// <value>
195 /// <see langword="true"/> if the <see cref="ICnmCache{TKey,TValue}"/> has a fixed total size of elements;
196 /// otherwise, <see langword="false"/>.
197 /// </value>
198 /// <remarks>
199 /// If <see cref="ICnmCache{TKey,TValue}"/> have limited inactivity time and element is not accessed through <see cref="Set"/>
200 /// or <see cref="TryGetValue"/> methods in <see cref="ExpirationTime"/> , then element is automatically removed from
201 /// the cache. Depending on implementation of the <see cref="ICnmCache{TKey,TValue}"/>, some of the elements may
202 /// stay longer in cache.
203 /// </remarks>
204 /// <seealso cref="ExpirationTime"/>
205 /// <seealso cref="PurgeExpired"/>
206 /// <seealso cref="IsCountLimited"/>
207 /// <seealso cref="IsSizeLimited"/>
208 bool IsTimeLimited { get; }
209
210 /// <summary>
211 /// Gets or sets maximal allowed count of elements that can be stored to <see cref="ICnmCache{TKey,TValue}"/>.
212 /// </summary>
213 /// <value>
214 /// <see cref="int.MaxValue"/>, if <see cref="ICnmCache{TKey,TValue}"/> is not limited by count of elements;
215 /// otherwise maximal allowed count of elements.
216 /// </value>
217 /// <remarks>
218 /// <para>
219 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
220 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
221 /// </para>
222 /// </remarks>
223 int MaxCount { get; set; }
224
225 /// <summary>
226 /// <para>Gets maximal allowed element size.</para>
227 /// </summary>
228 /// <value>
229 /// Maximal allowed element size.
230 /// </value>
231 /// <remarks>
232 /// <para>
233 /// If element's size is larger than <see cref="MaxElementSize"/>, then element is
234 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>.
235 /// </para>
236 /// </remarks>
237 /// <seealso cref="Set"/>
238 /// <seealso cref="IsSizeLimited"/>
239 /// <seealso cref="Size"/>
240 /// <seealso cref="MaxSize"/>
241 long MaxElementSize { get; }
242
243 /// <summary>
244 /// Gets or sets maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
245 /// </summary>
246 /// <value>
247 /// Maximal allowed total size for elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
248 /// </value>
249 /// <remarks>
250 /// <para>
251 /// Normally size is total bytes used by elements in the cache. But it can be any other suitable unit of measure.
252 /// </para>
253 /// <para>
254 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
255 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
256 /// </para>
257 /// </remarks>
258 /// <exception cref="ArgumentOutOfRangeException">value is less than 0.</exception>
259 /// <seealso cref="MaxElementSize"/>
260 /// <seealso cref="IsSizeLimited"/>
261 /// <seealso cref="Size"/>
262 long MaxSize { get; set; }
263
264 /// <summary>
265 /// Gets total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
266 /// </summary>
267 /// <value>
268 /// Total size of elements stored to <see cref="ICnmCache{TKey,TValue}"/>.
269 /// </value>
270 /// <remarks>
271 /// <para>
272 /// Normally bytes, but can be any suitable unit of measure.
273 /// </para>
274 /// <para>
275 /// Element's size is given when element is added or replaced by <see cref="Set"/> method.
276 /// </para>
277 /// <para>
278 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
279 /// <see cref="ICnmCache{TKey,TValue}"/> will remove less recently used elements until it can fit an new element.
280 /// </para>
281 /// </remarks>
282 /// <seealso cref="MaxElementSize"/>
283 /// <seealso cref="IsSizeLimited"/>
284 /// <seealso cref="MaxSize"/>
285 /// <seealso cref="IsCountLimited"/>
286 /// <seealso cref="ExpirationTime"/>
287 long Size { get; }
288
289 /// <summary>
290 /// Gets an object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
291 /// </summary>
292 /// <value>
293 /// An object that can be used to synchronize access to the <see cref="ICnmCache{TKey,TValue}"/>.
294 /// </value>
295 /// <remarks>
296 /// <para>
297 /// To get synchronized (thread safe) access to <see cref="ICnmCache{TKey,TValue}"/>, use <see cref="CnmSynchronizedCache{TKey,TValue}"/>
298 /// method <see cref="CnmSynchronizedCache{TKey,TValue}.Synchronized"/> to retrieve synchronized wrapper interface to
299 /// <see cref="ICnmCache{TKey,TValue}"/>.
300 /// </para>
301 /// </remarks>
302 /// <seealso cref="IsSynchronized"/>
303 /// <seealso cref="CnmSynchronizedCache{TKey,TValue}"/>
304 object SyncRoot { get; }
305
306 /// <summary>
307 /// Removes all elements from the <see cref="ICnmCache{TKey,TValue}"/>.
308 /// </summary>
309 /// <seealso cref="Set"/>
310 /// <seealso cref="Remove"/>
311 /// <seealso cref="RemoveRange"/>
312 /// <seealso cref="TryGetValue"/>
313 /// <seealso cref="PurgeExpired"/>
314 void Clear();
315
316 /// <summary>
317 /// Purge expired elements from the <see cref="ICnmCache{TKey,TValue}"/>.
318 /// </summary>
319 /// <remarks>
320 /// <para>
321 /// Element becomes expired when last access time to it has been longer time than <see cref="ExpirationTime"/>.
322 /// </para>
323 /// <para>
324 /// Depending on <see cref="ICnmCache{TKey,TValue}"/> implementation, some of expired elements
325 /// may stay longer than <see cref="ExpirationTime"/> in the cache.
326 /// </para>
327 /// </remarks>
328 /// <seealso cref="IsTimeLimited"/>
329 /// <seealso cref="ExpirationTime"/>
330 /// <seealso cref="Set"/>
331 /// <seealso cref="Remove"/>
332 /// <seealso cref="RemoveRange"/>
333 /// <seealso cref="TryGetValue"/>
334 /// <seealso cref="Clear"/>
335 void PurgeExpired();
336
337 /// <summary>
338 /// Removes element associated with <paramref name="key"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
339 /// </summary>
340 /// <param name="key">
341 /// The key that is associated with element to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
342 /// </param>
343 /// <exception cref="ArgumentNullException">
344 /// <paramref name="key"/> is <see langword="null"/>.
345 /// </exception>
346 /// <seealso cref="Set"/>
347 /// <seealso cref="RemoveRange"/>
348 /// <seealso cref="TryGetValue"/>
349 /// <seealso cref="Clear"/>
350 /// <seealso cref="PurgeExpired"/>
351 void Remove( TKey key );
352
353 /// <summary>
354 /// Removes elements that are associated with one of <paramref name="keys"/> from the <see cref="ICnmCache{TKey,TValue}"/>.
355 /// </summary>
356 /// <param name="keys">
357 /// The keys that are associated with elements to remove from the <see cref="ICnmCache{TKey,TValue}"/>.
358 /// </param>
359 /// <exception cref="ArgumentNullException">
360 /// <paramref name="keys"/> is <see langword="null"/>.
361 /// </exception>
362 /// <seealso cref="Set"/>
363 /// <seealso cref="Remove"/>
364 /// <seealso cref="TryGetValue"/>
365 /// <seealso cref="Clear"/>
366 /// <seealso cref="PurgeExpired"/>
367 void RemoveRange( IEnumerable<TKey> keys );
368
369 /// <summary>
370 /// Add or replace an element with the provided <paramref name="key"/>, <paramref name="value"/> and <paramref name="size"/> to
371 /// <see cref="ICnmCache{TKey,TValue}"/>.
372 /// </summary>
373 /// <param name="key">
374 /// The object used as the key of the element. Can't be <see langword="null"/> reference.
375 /// </param>
376 /// <param name="value">
377 /// The object used as the value of the element to add or replace. <see langword="null"/> is allowed.
378 /// </param>
379 /// <param name="size">
380 /// The element's size. Normally bytes, but can be any suitable unit of measure.
381 /// </param>
382 /// <returns>
383 /// <see langword="true"/> if element has been added successfully to the <see cref="ICnmCache{TKey,TValue}"/>;
384 /// otherwise <see langword="false"/>.
385 /// </returns>
386 /// <exception cref="ArgumentNullException">
387 /// <paramref name="key"/>is <see langword="null"/>.
388 /// </exception>
389 /// <exception cref="ArgumentOutOfRangeException">
390 /// The element's <paramref name="size"/> is less than 0.
391 /// </exception>
392 /// <remarks>
393 /// <para>
394 /// If element's <paramref name="size"/> is larger than <see cref="MaxElementSize"/>, then element is
395 /// not added to the <see cref="ICnmCache{TKey,TValue}"/>, however - possible older element is
396 /// removed from the <see cref="ICnmCache{TKey,TValue}"/>.
397 /// </para>
398 /// <para>
399 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting total size of elements,
400 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
401 /// </para>
402 /// <para>
403 /// When adding an new element to <see cref="ICnmCache{TKey,TValue}"/> that is limiting element count,
404 /// <see cref="ICnmCache{TKey,TValue}"/>will remove less recently used elements until it can fit an new element.
405 /// </para>
406 /// </remarks>
407 /// <seealso cref="IsSizeLimited"/>
408 /// <seealso cref="IsCountLimited"/>
409 /// <seealso cref="Remove"/>
410 /// <seealso cref="RemoveRange"/>
411 /// <seealso cref="TryGetValue"/>
412 /// <seealso cref="Clear"/>
413 /// <seealso cref="PurgeExpired"/>
414 bool Set( TKey key, TValue value, long size );
415
416 /// <summary>
417 /// Gets the <paramref name="value"/> associated with the specified <paramref name="key"/>.
418 /// </summary>
419 /// <returns>
420 /// <see langword="true"/>if the <see cref="ICnmCache{TKey,TValue}"/> contains an element with
421 /// the specified key; otherwise, <see langword="false"/>.
422 /// </returns>
423 /// <param name="key">
424 /// The key whose <paramref name="value"/> to get.
425 /// </param>
426 /// <param name="value">
427 /// When this method returns, the value associated with the specified <paramref name="key"/>,
428 /// if the <paramref name="key"/> is found; otherwise, the
429 /// default value for the type of the <paramref name="value"/> parameter. This parameter is passed uninitialized.
430 /// </param>
431 /// <exception cref="ArgumentNullException">
432 /// <paramref name="key"/>is <see langword="null"/>.
433 /// </exception>
434 /// <seealso cref="Set"/>
435 /// <seealso cref="Remove"/>
436 /// <seealso cref="RemoveRange"/>
437 /// <seealso cref="Clear"/>
438 /// <seealso cref="PurgeExpired"/>
439 bool TryGetValue( TKey key, out TValue value );
440 }
441}
diff --git a/OpenSim/Framework/PrimeNumberHelper.cs b/OpenSim/Framework/PrimeNumberHelper.cs
new file mode 100644
index 0000000..e4bf615
--- /dev/null
+++ b/OpenSim/Framework/PrimeNumberHelper.cs
@@ -0,0 +1,98 @@
1// --------------------------------------------------------------------------------------------------------------------
2// <copyright company="" file="PrimeNumberHelper.cs">
3//
4// </copyright>
5// <summary>
6//
7// </summary>
8//
9// --------------------------------------------------------------------------------------------------------------------
10
11using System;
12
13namespace OpenSim.Framework
14{
15 /// <summary>
16 /// Utility class that is used to find small prime numbers and test is number prime number.
17 /// </summary>
18 public static class PrimeNumberHelper
19 {
20 /// <summary>
21 /// Precalculated prime numbers.
22 /// </summary>
23 private static readonly int[] Primes = new int[]
24 {
25 3, 7, 11, 17, 23, 29, 37, 47, 59, 71, 89, 107, 131, 163, 197, 239,
26 293, 353, 431, 521, 631, 761, 919, 1103, 1327, 1597, 1931, 2333,
27 2801, 3371, 4049, 4861, 5839, 7013, 8419, 10103, 12143, 14591,
28 17519, 21023, 25229, 30293, 36353, 43627, 52361, 62851, 75431,
29 90523, 108631, 130363, 156437, 187751, 225307, 270371, 324449,
30 389357, 467237, 560689, 672827, 807403, 968897, 1162687, 1395263,
31 1674319, 2009191, 2411033, 2893249, 3471899, 4166287, 4999559,
32 5999471, 7199369
33 };
34
35 /// <summary>
36 /// Get prime number that is equal or larger than <see cref="min"/>.
37 /// </summary>
38 /// <param name="min">
39 /// Minimal returned prime number.
40 /// </param>
41 /// <returns>
42 /// Primer number that is equal or larger than <see cref="min"/>. If <see cref="min"/> is too large, return -1.
43 /// </returns>
44 public static int GetPrime( int min )
45 {
46 if( min <= 2 )
47 return 2;
48
49 if( Primes[ Primes.Length - 1 ] < min )
50 {
51 for( int i = min | 1 ; i < 0x7FFFFFFF ; i += 2 )
52 {
53 if( IsPrime( i ) )
54 return i;
55 }
56
57 return -1;
58 }
59
60 for( int i = Primes.Length - 2 ; i >= 0 ; i-- )
61 {
62 if( min == Primes[ i ] )
63 return min;
64
65 if( min > Primes[ i ] )
66 return Primes[ i + 1 ];
67 }
68
69 return 2;
70 }
71
72 /// <summary>
73 /// Just basic Sieve of Eratosthenes prime number test.
74 /// </summary>
75 /// <param name="candinate">
76 /// Number that is tested.
77 /// </param>
78 /// <returns>
79 /// true, if <see cref="candinate"/> is prime number; otherwise false.
80 /// </returns>
81 public static bool IsPrime( int candinate )
82 {
83 if( (candinate & 1) == 0 )
84
85 // Even number - only prime if 2
86 return candinate == 2;
87
88 int upperBound = (int) Math.Sqrt( candinate );
89 for( int i = 3 ; i < upperBound ; i += 2 )
90 {
91 if( candinate % i == 0 )
92 return false;
93 }
94
95 return true;
96 }
97 }
98}
diff --git a/OpenSim/Region/CoreModules/Asset/CenomeAssetCache.cs b/OpenSim/Region/CoreModules/Asset/CenomeAssetCache.cs
new file mode 100644
index 0000000..00a8143
--- /dev/null
+++ b/OpenSim/Region/CoreModules/Asset/CenomeAssetCache.cs
@@ -0,0 +1,382 @@
1// --------------------------------------------------------------------------------------------------------------------
2// <copyright company="" file="CenomeAssetCache.cs">
3//
4// </copyright>
5// <summary>
6//
7// </summary>
8//
9// --------------------------------------------------------------------------------------------------------------------
10using System;
11using System.Reflection;
12using log4net;
13using Nini.Config;
14using OpenSim.Framework;
15using OpenSim.Region.Framework.Interfaces;
16using OpenSim.Region.Framework.Scenes;
17
18namespace OpenSim.Region.CoreModules.Asset
19{
20 /// <summary>
21 /// Cenome memory asset cache.
22 /// </summary>
23 /// <remarks>
24 /// <para>
25 /// Cache is enabled by setting "AssetCaching" configuration to value "CenomeMemoryAssetCache".
26 /// When cache is successfully enable log should have message
27 /// "[ASSET CACHE]: Cenome asset cache enabled (MaxSize = XXX bytes, MaxCount = XXX, ExpirationTime = XXX)".
28 /// </para>
29 /// <para>
30 /// Cache's size is limited by two parameters:
31 /// maximal allowed size in bytes and maximal allowed asset count. When new asset
32 /// is added to cache that have achieved either size or count limitation, cache
33 /// will automatically remove less recently used assets from cache. Additionally
34 /// asset's lifetime is controlled by expiration time.
35 /// </para>
36 /// <para>
37 /// <list type="table">
38 /// <listheader>
39 /// <term>Configuration</term>
40 /// <description>Description</description>
41 /// </listheader>
42 /// <item>
43 /// <term>MaxSize</term>
44 /// <description>Maximal size of the cache in bytes. Default value: 128MB (134 217 728 bytes).</description>
45 /// </item>
46 /// <item>
47 /// <term>MaxCount</term>
48 /// <description>Maximal count of assets stored to cache. Default value: 4096 assets.</description>
49 /// </item>
50 /// <item>
51 /// <term>ExpirationTime</term>
52 /// <description>Asset's expiration time in minutes. Default value: 30 minutes.</description>
53 /// </item>
54 /// </list>
55 /// </para>
56 /// </remarks>
57 /// <example>
58 /// Enabling Cenome Asset Cache:
59 /// <code>
60 /// [Modules]
61 /// AssetCaching = "CenomeMemoryAssetCache"
62 /// </code>
63 /// Setting size and expiration time limitations:
64 /// <code>
65 /// [AssetService]
66 /// ; 256 MB (default: 134217728)
67 /// MaxSize = 268435456
68 /// ; How many assets it is possible to store cache (default: 4096)
69 /// MaxCount = 16384
70 /// ; Expiration time - 1 hour (default: 30 minutes)
71 /// ExpirationTime = 60
72 /// </code>
73 /// </example>
74 public class CenomeMemoryAssetCache : IImprovedAssetCache, ISharedRegionModule
75 {
76 /// <summary>
77 /// Cache's default maximal asset count.
78 /// </summary>
79 /// <remarks>
80 /// <para>
81 /// Assuming that average asset size is about 32768 bytes.
82 /// </para>
83 /// </remarks>
84 public const int DefaultMaxCount = 4096;
85
86 /// <summary>
87 /// Default maximal size of the cache in bytes
88 /// </summary>
89 /// <remarks>
90 /// <para>
91 /// 128MB = 128 * 1024^2 = 134 217 728 bytes.
92 /// </para>
93 /// </remarks>
94 public const long DefaultMaxSize = 134217728;
95
96 /// <summary>
97 /// Asset's default expiration time in the cache.
98 /// </summary>
99 public static readonly TimeSpan DefaultExpirationTime = TimeSpan.FromMinutes( 30.0 );
100
101 /// <summary>
102 /// Log manager instance.
103 /// </summary>
104 private static readonly ILog Log = LogManager.GetLogger( MethodBase.GetCurrentMethod().DeclaringType );
105
106 /// <summary>
107 /// Cache object.
108 /// </summary>
109 private ICnmCache<string, AssetBase> m_cache;
110
111 /// <summary>
112 /// Count of cache commands
113 /// </summary>
114 private int m_cachedCount;
115
116 /// <summary>
117 /// How many gets before dumping statistics
118 /// </summary>
119 /// <remarks>
120 /// If 0 or less, then disabled.
121 /// </remarks>
122 private int m_debugEpoch;
123
124 /// <summary>
125 /// Is Cenome asset cache enabled.
126 /// </summary>
127 private bool m_enabled;
128
129 /// <summary>
130 /// Count of get requests
131 /// </summary>
132 private int m_getCount;
133
134 /// <summary>
135 /// How many hits
136 /// </summary>
137 private int m_hitCount;
138
139 /// <summary>
140 /// Initialize asset cache module with default parameters.
141 /// </summary>
142 public void Initialize()
143 {
144 Initialize( DefaultMaxSize, DefaultMaxCount, DefaultExpirationTime );
145 }
146
147 /// <summary>
148 /// Initialize asset cache module, with custom parameters.
149 /// </summary>
150 /// <param name="maximalSize">
151 /// Cache's maximal size in bytes.
152 /// </param>
153 /// <param name="maximalCount">
154 /// Cache's maximal count of assets.
155 /// </param>
156 /// <param name="expirationTime">
157 /// Asset's expiration time.
158 /// </param>
159 public void Initialize( long maximalSize, int maximalCount, TimeSpan expirationTime )
160 {
161 if( maximalSize <= 0 || maximalCount <= 0 )
162 {
163 Log.Info( "[ASSET CACHE]: Cenome asset cache is not enabled." );
164 m_enabled = false;
165 return;
166 }
167
168 if( expirationTime <= TimeSpan.Zero )
169 {
170 // Disable expiration time
171 expirationTime = TimeSpan.MaxValue;
172 }
173
174 // Create cache and add synchronization wrapper over it
175 m_cache =
176 CnmSynchronizedCache<string, AssetBase>.Synchronized( new CnmMemoryCache<string, AssetBase>(
177 maximalSize, maximalCount, expirationTime ) );
178 m_enabled = true;
179 Log.InfoFormat(
180 "[ASSET CACHE]: Cenome asset cache enabled (MaxSize = {0} bytes, MaxCount = {1}, ExpirationTime = {2})",
181 maximalSize,
182 maximalCount,
183 expirationTime );
184 }
185
186 #region IImprovedAssetCache Members
187
188 /// <summary>
189 /// Cache asset.
190 /// </summary>
191 /// <param name="asset">
192 /// The asset that is being cached.
193 /// </param>
194 public void Cache( AssetBase asset )
195 {
196 long size = asset.Data != null ? asset.Data.Length : 1;
197 m_cache.Set( asset.ID, asset, size );
198 m_cachedCount++;
199 }
200
201 /// <summary>
202 /// Clear asset cache.
203 /// </summary>
204 public void Clear()
205 {
206 m_cache.Clear();
207 }
208
209 /// <summary>
210 /// Expire (remove) asset stored to cache.
211 /// </summary>
212 /// <param name="id">
213 /// The expired asset's id.
214 /// </param>
215 public void Expire( string id )
216 {
217 m_cache.Remove( id );
218 }
219
220 /// <summary>
221 /// Get asset stored
222 /// </summary>
223 /// <param name="id">
224 /// The asset's id.
225 /// </param>
226 /// <returns>
227 /// Asset if it is found from cache; otherwise <see langword="null"/>.
228 /// </returns>
229 /// <remarks>
230 /// <para>
231 /// Caller should always check that is return value <see langword="null"/>.
232 /// Cache doesn't guarantee in any situation that asset is stored to it.
233 /// </para>
234 /// </remarks>
235 public AssetBase Get( string id )
236 {
237 m_getCount++;
238 AssetBase assetBase;
239 if( m_cache.TryGetValue( id, out assetBase ) )
240 m_hitCount++;
241
242 if( m_getCount == m_debugEpoch )
243 {
244 Log.InfoFormat(
245 "[ASSET CACHE]: Cached = {0}, Get = {1}, Hits = {2}%, Size = {3} bytes, Avg. A. Size = {4} bytes",
246 m_cachedCount,
247 m_getCount,
248 ((double) m_hitCount / m_getCount) * 100.0,
249 m_cache.Size,
250 m_cache.Size / m_cache.Count );
251 m_getCount = 0;
252 m_hitCount = 0;
253 m_cachedCount = 0;
254 }
255
256 return assetBase;
257 }
258
259 #endregion
260
261 #region ISharedRegionModule Members
262
263 /// <summary>
264 /// Gets region module's name.
265 /// </summary>
266 public string Name
267 {
268 get { return "CenomeMemoryAssetCache"; }
269 }
270
271 /// <summary>
272 /// New region is being added to server.
273 /// </summary>
274 /// <param name="scene">
275 /// Region's scene.
276 /// </param>
277 public void AddRegion( Scene scene )
278 {
279 if( m_enabled )
280 scene.RegisterModuleInterface<IImprovedAssetCache>( this );
281 }
282
283 /// <summary>
284 /// Close region module.
285 /// </summary>
286 public void Close()
287 {
288 m_enabled = false;
289 m_cache.Clear();
290 m_cache = null;
291 }
292
293 /// <summary>
294 /// Initialize region module.
295 /// </summary>
296 /// <param name="source">
297 /// Configuration source.
298 /// </param>
299 public void Initialise( IConfigSource source )
300 {
301 m_cache = null;
302 m_enabled = false;
303
304 IConfig moduleConfig = source.Configs[ "Modules" ];
305 if( moduleConfig == null )
306 return;
307
308 string name = moduleConfig.GetString( "AssetCaching" );
309 Log.DebugFormat( "[XXX] name = {0} (this module's name: {1}", name, Name );
310
311 if( name != Name )
312 return;
313
314 // This module is used
315 long maxSize = DefaultMaxSize;
316 int maxCount = DefaultMaxCount;
317 TimeSpan expirationTime = DefaultExpirationTime;
318
319 IConfig assetConfig = source.Configs[ "AssetCache" ];
320 if( assetConfig != null )
321 {
322 // Get optional configurations
323 maxSize = assetConfig.GetLong( "MaxSize", DefaultMaxSize );
324 maxCount = assetConfig.GetInt( "MaxCount", DefaultMaxCount );
325 expirationTime =
326 TimeSpan.FromMinutes( assetConfig.GetInt( "ExpirationTime", (int) DefaultExpirationTime.TotalMinutes ) );
327
328 // Debugging purposes only
329 m_debugEpoch = assetConfig.GetInt( "DebugEpoch", 0 );
330 }
331
332 Initialize( maxSize, maxCount, expirationTime );
333 }
334
335 /// <summary>
336 /// Initialization post handling.
337 /// </summary>
338 /// <remarks>
339 /// <para>
340 /// Modules can use this to initialize connection with other modules.
341 /// </para>
342 /// </remarks>
343 public void PostInitialise()
344 {
345 }
346
347 /// <summary>
348 /// Region has been loaded.
349 /// </summary>
350 /// <param name="scene">
351 /// Region's scene.
352 /// </param>
353 /// <remarks>
354 /// <para>
355 /// This is needed for all module types. Modules will register
356 /// Interfaces with scene in AddScene, and will also need a means
357 /// to access interfaces registered by other modules. Without
358 /// this extra method, a module attempting to use another modules'
359 /// interface would be successful only depending on load order,
360 /// which can't be depended upon, or modules would need to resort
361 /// to ugly kludges to attempt to request interfaces when needed
362 /// and unnecessary caching logic repeated in all modules.
363 /// The extra function stub is just that much cleaner.
364 /// </para>
365 /// </remarks>
366 public void RegionLoaded( Scene scene )
367 {
368 }
369
370 /// <summary>
371 /// Region is being removed.
372 /// </summary>
373 /// <param name="scene">
374 /// Region scene that is being removed.
375 /// </param>
376 public void RemoveRegion( Scene scene )
377 {
378 }
379
380 #endregion
381 }
382}
diff --git a/OpenSim/Region/CoreModules/Resources/CoreModulePlugin.addin.xml b/OpenSim/Region/CoreModules/Resources/CoreModulePlugin.addin.xml
index 393f340..9969ebe 100644
--- a/OpenSim/Region/CoreModules/Resources/CoreModulePlugin.addin.xml
+++ b/OpenSim/Region/CoreModules/Resources/CoreModulePlugin.addin.xml
@@ -19,6 +19,7 @@
19 <RegionModule id="HGAssetBroker" type="OpenSim.Region.CoreModules.ServiceConnectors.Asset.HGAssetBroker" /> 19 <RegionModule id="HGAssetBroker" type="OpenSim.Region.CoreModules.ServiceConnectors.Asset.HGAssetBroker" />
20 <RegionModule id="CoreAssetCache" type="OpenSim.Region.CoreModules.Asset.CoreAssetCache" /> 20 <RegionModule id="CoreAssetCache" type="OpenSim.Region.CoreModules.Asset.CoreAssetCache" />
21 <RegionModule id="CoreAssetCache" type="OpenSim.Region.CoreModules.Asset.GlynnTuckerAssetCache" /> 21 <RegionModule id="CoreAssetCache" type="OpenSim.Region.CoreModules.Asset.GlynnTuckerAssetCache" />
22 <RegionModule id="CenomeMemoryAssetCache" type="OpenSim.Region.CoreModules.Asset.CenomeMemoryAssetCache"/>
22 <RegionModule id="UrlModule" type="OpenSim.Region.CoreModules.Scripting.LSLHttp.UrlModule" /> 23 <RegionModule id="UrlModule" type="OpenSim.Region.CoreModules.Scripting.LSLHttp.UrlModule" />
23 <RegionModule id="Chat" type="OpenSim.Region.CoreModules.Avatar.Chat.ChatModule" /> 24 <RegionModule id="Chat" type="OpenSim.Region.CoreModules.Avatar.Chat.ChatModule" />
24 </Extension> 25 </Extension>
diff --git a/bin/config-include/GridCommon.ini.example b/bin/config-include/GridCommon.ini.example
index 8a95776..3825374 100644
--- a/bin/config-include/GridCommon.ini.example
+++ b/bin/config-include/GridCommon.ini.example
@@ -1,6 +1,7 @@
1[Modules] 1[Modules]
2 ;AssetCaching = "CoreAssetCache" 2 ;AssetCaching = "CoreAssetCache"
3 AssetCaching = "GlynnTuckerAssetCache" 3 AssetCaching = "GlynnTuckerAssetCache"
4 ;AssetCaching = "CenomeMemoryAssetCache"
4 5
5[AssetCache] 6[AssetCache]
6 ; Number of buckets for assets 7 ; Number of buckets for assets
@@ -16,3 +17,10 @@
16 ; 17 ;
17 AssetServerURI = "http://myassetserver.com:8003" 18 AssetServerURI = "http://myassetserver.com:8003"
18 19
20 ; Optional configurations for CenomeMemoryAssetCache
21 ; Cache size 128 MB (default: 134217728)
22 ; MaxSize = 134217728
23 ; Maximal asset count
24 ; MaxCount = 4096
25 ; Asset's expiration time (minutes)
26 ; ExpirationTime = 30 \ No newline at end of file
diff --git a/bin/config-include/StandaloneCommon.ini.example b/bin/config-include/StandaloneCommon.ini.example
index d607092..d772256 100644
--- a/bin/config-include/StandaloneCommon.ini.example
+++ b/bin/config-include/StandaloneCommon.ini.example
@@ -1,6 +1,7 @@
1[Modules] 1[Modules]
2 ;AssetCaching = "CoreAssetCache" 2 ;AssetCaching = "CoreAssetCache"
3 AssetCaching = "GlynnTuckerAssetCache" 3 AssetCaching = "GlynnTuckerAssetCache"
4 ;AssetCaching = "CenomeMemoryAssetCache"
4 5
5[AssetCache] 6[AssetCache]
6 ; Number of buckets for assets 7 ; Number of buckets for assets
@@ -20,3 +21,10 @@
20 AssetLoaderArgs = "assets/AssetSets.xml" 21 AssetLoaderArgs = "assets/AssetSets.xml"
21 22
22 23
24 ; Optional configurations for CenomeMemoryAssetCache
25 ; Cache size 128 MB (default: 134217728)
26 ; MaxSize = 134217728
27 ; Maximal asset count
28 ; MaxCount = 4096
29 ; Asset's expiration time (minutes)
30 ; ExpirationTime = 30 \ No newline at end of file