1//
2// ExpireCache.h
3//
4// Library: Foundation
5// Package: Cache
6// Module: ExpireCache
7//
8// Definition of the ExpireCache 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_ExpireCache_INCLUDED
18#define Foundation_ExpireCache_INCLUDED
19
20
21#include "Poco/AbstractCache.h"
22#include "Poco/ExpireStrategy.h"
23
24
25namespace Poco {
26
27
28template <
29 class TKey,
30 class TValue,
31 class TMutex = FastMutex,
32 class TEventMutex = FastMutex
33>
34class ExpireCache: public AbstractCache<TKey, TValue, ExpireStrategy<TKey, TValue>, TMutex, TEventMutex>
35 /// An ExpireCache caches entries for a fixed time period (per default 10 minutes).
36 /// Entries expire independently of the access pattern, i.e. after a constant time.
37 /// If you require your objects to expire after they were not accessed for a given time
38 /// period use a Poco::AccessExpireCache.
39 ///
40 /// Be careful when using an ExpireCache. A cache is often used
41 /// like cache.has(x) followed by cache.get x). Note that it could happen
42 /// that the "has" call works, then the current execution thread gets descheduled, time passes,
43 /// the entry gets invalid, thus leading to an empty SharedPtr being returned
44 /// when "get" is invoked.
45{
46public:
47 ExpireCache(Timestamp::TimeDiff expire = 600000):
48 AbstractCache<TKey, TValue, ExpireStrategy<TKey, TValue>, TMutex, TEventMutex>(ExpireStrategy<TKey, TValue>(expire))
49 {
50 }
51
52 ~ExpireCache()
53 {
54 }
55
56private:
57 ExpireCache(const ExpireCache& aCache);
58 ExpireCache& operator = (const ExpireCache& aCache);
59};
60
61
62} // namespace Poco
63
64
65#endif // Foundation_ExpireCache_INCLUDED
66