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//

// AccessExpireCache.h

//

// $Id: //poco/1.3/Foundation/include/Poco/AccessExpireCache.h#1 $

//

// Library: Foundation

// Package: Cache

// Module:  AccessExpireCache

//

// Definition of the AccessExpireCache 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,

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// DEALINGS IN THE SOFTWARE.

//

#ifndef  Foundation_AccessExpireCache_INCLUDED

#define  Foundation_AccessExpireCache_INCLUDED

#include "Poco/AbstractCache.h"

#include "Poco/AccessExpireStrategy.h"

namespace Poco {

template <class TKey, class TValue> 

class AccessExpireCache: public AbstractCache<TKey, TValue, AccessExpireStrategy<TKey, TValue> >

        /// 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<TKey, TValue, AccessExpireStrategy<TKey, TValue> >(AccessExpireStrategy<TKey, TValue>(expire))

        {

        }

        ~AccessExpireCache()

        {

        }

private:

        AccessExpireCache(const AccessExpireCache& aCache);

        AccessExpireCache& operator = (const AccessExpireCache& aCache);

};

} // namespace Poco

#endif // Foundation_AccessExpireCache_INCLUDED