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60 lines
1.6 KiB
C++
60 lines
1.6 KiB
C++
//
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// ExpireCache.h
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//
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// Library: Foundation
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// Package: Cache
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// Module: ExpireCache
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//
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// Definition of the ExpireCache 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_ExpireCache_INCLUDED
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#define Foundation_ExpireCache_INCLUDED
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#include "Poco/AbstractCache.h"
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#include "Poco/ExpireStrategy.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 ExpireCache : public AbstractCache<TKey, TValue, ExpireStrategy<TKey, TValue>, TMutex, TEventMutex>
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/// An ExpireCache caches entries for a fixed time period (per default 10 minutes).
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/// Entries expire independently of the access pattern, i.e. after a constant time.
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/// If you require your objects to expire after they were not accessed for a given time
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/// period use a Poco::AccessExpireCache.
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///
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/// Be careful when using an ExpireCache. A cache is often used
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/// like cache.has(x) followed by cache.get x). Note that it could happen
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/// that the "has" call works, then the current execution thread gets descheduled, time passes,
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/// the entry gets invalid, thus leading to an empty SharedPtr being returned
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/// when "get" is invoked.
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{
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public:
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ExpireCache(Timestamp::TimeDiff expire = 600000)
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: AbstractCache<TKey, TValue, ExpireStrategy<TKey, TValue>, TMutex, TEventMutex>(ExpireStrategy<TKey, TValue>(expire))
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{
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}
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~ExpireCache() { }
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private:
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ExpireCache(const ExpireCache & aCache);
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ExpireCache & operator=(const ExpireCache & aCache);
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};
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} // namespace Poco
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#endif // Foundation_ExpireCache_INCLUDED
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