1//
2// AccessExpireCache.h
3//
4// Library: Foundation
5// Package: Cache
6// Module: AccessExpireCache
7//
8// Definition of the AccessExpireCache class.
9//
10// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
11// and Contributors.
12//
13// SPDX-License-Identifier: BSL-1.0
14//
15
16
17#ifndef Foundation_AccessExpireCache_INCLUDED
18#define Foundation_AccessExpireCache_INCLUDED
19
20
21#include "Poco/AbstractCache.h"
22#include "Poco/AccessExpireStrategy.h"
23
24
25namespace Poco {
26
27
28template <
29 class TKey,
30 class TValue,
31 class TMutex = FastMutex,
32 class TEventMutex = FastMutex
33>
34class AccessExpireCache: public AbstractCache<TKey, TValue, AccessExpireStrategy<TKey, TValue>, TMutex, TEventMutex>
35 /// An AccessExpireCache caches entries for a fixed time period (per default 10 minutes).
36 /// Entries expire when they are not accessed with get() during this time period. Each access resets
37 /// the start time for expiration.
38 /// Be careful when using an AccessExpireCache. A cache is often used
39 /// like cache.has(x) followed by cache.get x). Note that it could happen
40 /// that the "has" call works, then the current execution thread gets descheduled, time passes,
41 /// the entry gets invalid, thus leading to an empty SharedPtr being returned
42 /// when "get" is invoked.
43{
44public:
45 AccessExpireCache(Timestamp::TimeDiff expire = 600000):
46 AbstractCache<TKey, TValue, AccessExpireStrategy<TKey, TValue>, TMutex, TEventMutex>(AccessExpireStrategy<TKey, TValue>(expire))
47 {
48 }
49
50 ~AccessExpireCache()
51 {
52 }
53
54private:
55 AccessExpireCache(const AccessExpireCache& aCache);
56 AccessExpireCache& operator = (const AccessExpireCache& aCache);
57};
58
59
60} // namespace Poco
61
62
63#endif // Foundation_AccessExpireCache_INCLUDED
64