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//
// 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<TKey, TValue, AccessExpireStrategy<TKey, TValue>, 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<TKey, TValue, AccessExpireStrategy<TKey, TValue>, TMutex, TEventMutex>(AccessExpireStrategy<TKey, TValue>(expire))
{
}
~AccessExpireCache()
{
}
private:
AccessExpireCache(const AccessExpireCache& aCache);
AccessExpireCache& operator = (const AccessExpireCache& aCache);
};
} // namespace Poco
#endif // Foundation_AccessExpireCache_INCLUDED
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