// // ExpireCache.h // // $Id: //poco/1.4/Foundation/include/Poco/ExpireCache.h#1 $ // // Library: Foundation // Package: Cache // Module: ExpireCache // // Definition of the ExpireCache class. // // Copyright (c) 2006, Applied Informatics Software Engineering GmbH. // and Contributors. // // Permission is hereby granted, free of charge, to any person or organization // obtaining a copy of the software and accompanying documentation covered by // this license (the "Software") to use, reproduce, display, distribute, // execute, and transmit the Software, and to prepare derivative works of the // Software, and to permit third-parties to whom the Software is furnished to // do so, all subject to the following: // // The copyright notices in the Software and this entire statement, including // the above license grant, this restriction and the following disclaimer, // must be included in all copies of the Software, in whole or in part, and // all derivative works of the Software, unless such copies or derivative // works are solely in the form of machine-executable object code generated by // a source language processor. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT // SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE // FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER // DEALINGS IN THE SOFTWARE. // #ifndef Foundation_ExpireCache_INCLUDED #define Foundation_ExpireCache_INCLUDED #include "Poco/AbstractCache.h" #include "Poco/ExpireStrategy.h" namespace Poco { template < class TKey, class TValue, class TMutex = FastMutex, class TEventMutex = FastMutex > class ExpireCache: public AbstractCache, TMutex, TEventMutex> /// An ExpireCache caches entries for a fixed time period (per default 10 minutes). /// Entries expire independently of the access pattern, i.e. after a constant time. /// If you require your objects to expire after they were not accessed for a given time /// period use a Poco::AccessExpireCache. /// /// Be careful when using an ExpireCache. 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: ExpireCache(Timestamp::TimeDiff expire = 600000): AbstractCache, TMutex, TEventMutex>(ExpireStrategy(expire)) { } ~ExpireCache() { } private: ExpireCache(const ExpireCache& aCache); ExpireCache& operator = (const ExpireCache& aCache); }; } // namespace Poco #endif // Foundation_ExpireCache_INCLUDED