1//
2// UniqueAccessExpireLRUCache.h
3//
4// Library: Foundation
5// Package: Cache
6// Module: UniqueAccessExpireLRUCache
7//
8// Definition of the UniqueAccessExpireLRUCache class.
9//
10// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
11// and Contributors.
12//
13// SPDX-License-Identifier: BSL-1.0
14//
15
16
17#ifndef Foundation_UniqueAccessExpireLRUCache_INCLUDED
18#define Foundation_UniqueAccessExpireLRUCache_INCLUDED
19
20
21#include "Poco/AbstractCache.h"
22#include "Poco/StrategyCollection.h"
23#include "Poco/UniqueAccessExpireStrategy.h"
24#include "Poco/LRUStrategy.h"
25
26
27namespace Poco {
28
29
30template <
31 class TKey,
32 class TValue,
33 class TMutex = FastMutex,
34 class TEventMutex = FastMutex
35>
36class UniqueAccessExpireLRUCache: public AbstractCache<TKey, TValue, StrategyCollection<TKey, TValue>, TMutex, TEventMutex>
37 /// A UniqueAccessExpireLRUCache combines LRU caching and time based per entry expire caching.
38 /// One can define for each cache entry a separate timepoint
39 /// but also limit the size of the cache (per default: 1024).
40 /// Each TValue object must thus offer the following method:
41 ///
42 /// const Poco::Timespan& getTimeout() const;
43 ///
44 /// which returns the relative timespan for how long the entry should be valid without being accessed!
45 /// The absolute expire timepoint is calculated as now() + getTimeout().
46 /// Accessing an object will update this absolute expire timepoint.
47 /// You can use the Poco::AccessExpirationDecorator to add the getExpiration
48 /// method to values that do not have a getExpiration function.
49{
50public:
51 UniqueAccessExpireLRUCache(long cacheSize = 1024):
52 AbstractCache<TKey, TValue, StrategyCollection<TKey, TValue>, TMutex, TEventMutex>(StrategyCollection<TKey, TValue>())
53 {
54 this->_strategy.pushBack(new LRUStrategy<TKey, TValue>(cacheSize));
55 this->_strategy.pushBack(new UniqueAccessExpireStrategy<TKey, TValue>());
56 }
57
58 ~UniqueAccessExpireLRUCache()
59 {
60 }
61
62private:
63 UniqueAccessExpireLRUCache(const UniqueAccessExpireLRUCache& aCache);
64 UniqueAccessExpireLRUCache& operator = (const UniqueAccessExpireLRUCache& aCache);
65};
66
67
68} // namespace Poco
69
70
71#endif // Foundation_UniqueAccessExpireLRUCache_INCLUDED
72