1 | // |
2 | // SingletonHolder.h |
3 | // |
4 | // Library: Foundation |
5 | // Package: Core |
6 | // Module: SingletonHolder |
7 | // |
8 | // Definition of the SingletonHolder template. |
9 | // |
10 | // Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH. |
11 | // and Contributors. |
12 | // |
13 | // SPDX-License-Identifier: BSL-1.0 |
14 | // |
15 | |
16 | |
17 | #ifndef Foundation_SingletonHolder_INCLUDED |
18 | #define Foundation_SingletonHolder_INCLUDED |
19 | |
20 | |
21 | #include "Poco/Foundation.h" |
22 | #include "Poco/Mutex.h" |
23 | |
24 | |
25 | namespace Poco { |
26 | |
27 | |
28 | template <class S> |
29 | class SingletonHolder |
30 | /// This is a helper template class for managing |
31 | /// singleton objects allocated on the heap. |
32 | /// The class ensures proper deletion (including |
33 | /// calling of the destructor) of singleton objects |
34 | /// when the application that created them terminates. |
35 | { |
36 | public: |
37 | SingletonHolder(): |
38 | _pS(0) |
39 | /// Creates the SingletonHolder. |
40 | { |
41 | } |
42 | |
43 | ~SingletonHolder() |
44 | /// Destroys the SingletonHolder and the singleton |
45 | /// object that it holds. |
46 | { |
47 | delete _pS; |
48 | } |
49 | |
50 | S* get() |
51 | /// Returns a pointer to the singleton object |
52 | /// hold by the SingletonHolder. The first call |
53 | /// to get will create the singleton. |
54 | { |
55 | FastMutex::ScopedLock lock(_m); |
56 | if (!_pS) _pS = new S; |
57 | return _pS; |
58 | } |
59 | |
60 | void reset() |
61 | /// Deletes the singleton object. |
62 | { |
63 | FastMutex::ScopedLock lock(_m); |
64 | delete _pS; |
65 | _pS = 0; |
66 | } |
67 | |
68 | private: |
69 | S* _pS; |
70 | FastMutex _m; |
71 | }; |
72 | |
73 | |
74 | } // namespace Poco |
75 | |
76 | |
77 | #endif // Foundation_SingletonHolder_INCLUDED |
78 | |