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66 lines
2.1 KiB
C++
66 lines
2.1 KiB
C++
//
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// UniqueAccessExpireLRUCache.h
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//
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// Library: Foundation
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// Package: Cache
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// Module: UniqueAccessExpireLRUCache
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//
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// Definition of the UniqueAccessExpireLRUCache class.
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//
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// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
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// and Contributors.
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//
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// SPDX-License-Identifier: BSL-1.0
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//
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#ifndef Foundation_UniqueAccessExpireLRUCache_INCLUDED
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#define Foundation_UniqueAccessExpireLRUCache_INCLUDED
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#include "Poco/AbstractCache.h"
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#include "Poco/LRUStrategy.h"
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#include "Poco/StrategyCollection.h"
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#include "Poco/UniqueAccessExpireStrategy.h"
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namespace Poco
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{
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template <class TKey, class TValue, class TMutex = FastMutex, class TEventMutex = FastMutex>
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class UniqueAccessExpireLRUCache : public AbstractCache<TKey, TValue, StrategyCollection<TKey, TValue>, TMutex, TEventMutex>
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/// A UniqueAccessExpireLRUCache combines LRU caching and time based per entry expire caching.
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/// One can define for each cache entry a separate timepoint
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/// but also limit the size of the cache (per default: 1024).
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/// Each TValue object must thus offer the following method:
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///
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/// const Poco::Timespan& getTimeout() const;
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///
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/// which returns the relative timespan for how long the entry should be valid without being accessed!
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/// The absolute expire timepoint is calculated as now() + getTimeout().
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/// Accessing an object will update this absolute expire timepoint.
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/// You can use the Poco::AccessExpirationDecorator to add the getExpiration
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/// method to values that do not have a getExpiration function.
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{
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public:
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UniqueAccessExpireLRUCache(long cacheSize = 1024)
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: AbstractCache<TKey, TValue, StrategyCollection<TKey, TValue>, TMutex, TEventMutex>(StrategyCollection<TKey, TValue>())
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{
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this->_strategy.pushBack(new LRUStrategy<TKey, TValue>(cacheSize));
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this->_strategy.pushBack(new UniqueAccessExpireStrategy<TKey, TValue>());
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}
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~UniqueAccessExpireLRUCache() { }
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private:
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UniqueAccessExpireLRUCache(const UniqueAccessExpireLRUCache & aCache);
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UniqueAccessExpireLRUCache & operator=(const UniqueAccessExpireLRUCache & aCache);
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};
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} // namespace Poco
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#endif // Foundation_UniqueAccessExpireLRUCache_INCLUDED
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