// // AccessExpireCache.h // // Library: Foundation // Package: Cache // Module: AccessExpireCache // // Definition of the AccessExpireCache class. // // Copyright (c) 2006, Applied Informatics Software Engineering GmbH. // and Contributors. // // SPDX-License-Identifier: BSL-1.0 // #ifndef Foundation_AccessExpireCache_INCLUDED #define Foundation_AccessExpireCache_INCLUDED #include "Poco/AbstractCache.h" #include "Poco/AccessExpireStrategy.h" namespace Poco { template < class TKey, class TValue, class TMutex = FastMutex, class TEventMutex = FastMutex > class AccessExpireCache: public AbstractCache, TMutex, TEventMutex> /// An AccessExpireCache caches entries for a fixed time period (per default 10 minutes). /// Entries expire when they are not accessed with get() during this time period. Each access resets /// the start time for expiration. /// Be careful when using an AccessExpireCache. A cache is often used /// like cache.has(x) followed by cache.get x). Note that it could happen /// that the "has" call works, then the current execution thread gets descheduled, time passes, /// the entry gets invalid, thus leading to an empty SharedPtr being returned /// when "get" is invoked. { public: AccessExpireCache(Timestamp::TimeDiff expire = 600000): AbstractCache, TMutex, TEventMutex>(AccessExpireStrategy(expire)) { } ~AccessExpireCache() { } private: AccessExpireCache(const AccessExpireCache& aCache); AccessExpireCache& operator = (const AccessExpireCache& aCache); }; } // namespace Poco #endif // Foundation_AccessExpireCache_INCLUDED