1 | // |
2 | // DynamicFactory.h |
3 | // |
4 | // Library: Foundation |
5 | // Package: Core |
6 | // Module: DynamicFactory |
7 | // |
8 | // Definition of the DynamicFactory class. |
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_DynamicFactory_INCLUDED |
18 | #define Foundation_DynamicFactory_INCLUDED |
19 | |
20 | |
21 | #include "Poco/Foundation.h" |
22 | #include "Poco/Instantiator.h" |
23 | #include "Poco/Exception.h" |
24 | #include "Poco/Mutex.h" |
25 | #include <map> |
26 | #include <memory> |
27 | |
28 | |
29 | namespace Poco { |
30 | |
31 | |
32 | template <class Base> |
33 | class DynamicFactory |
34 | /// A factory that creates objects by class name. |
35 | { |
36 | public: |
37 | typedef AbstractInstantiator<Base> AbstractFactory; |
38 | |
39 | DynamicFactory() |
40 | /// Creates the DynamicFactory. |
41 | { |
42 | } |
43 | |
44 | ~DynamicFactory() |
45 | /// Destroys the DynamicFactory and deletes the instantiators for |
46 | /// all registered classes. |
47 | { |
48 | for (typename FactoryMap::iterator it = _map.begin(); it != _map.end(); ++it) |
49 | { |
50 | delete it->second; |
51 | } |
52 | } |
53 | |
54 | Base* createInstance(const std::string& className) const |
55 | /// Creates a new instance of the class with the given name. |
56 | /// The class must have been registered with registerClass. |
57 | /// If the class name is unknown, a NotFoundException is thrown. |
58 | { |
59 | FastMutex::ScopedLock lock(_mutex); |
60 | |
61 | typename FactoryMap::const_iterator it = _map.find(className); |
62 | if (it != _map.end()) |
63 | return it->second->createInstance(); |
64 | else |
65 | throw NotFoundException(className); |
66 | } |
67 | |
68 | template <class C> |
69 | void registerClass(const std::string& className) |
70 | /// Registers the instantiator for the given class with the DynamicFactory. |
71 | /// The DynamicFactory takes ownership of the instantiator and deletes |
72 | /// it when it's no longer used. |
73 | /// If the class has already been registered, an ExistsException is thrown |
74 | /// and the instantiator is deleted. |
75 | { |
76 | registerClass(className, new Instantiator<C, Base>); |
77 | } |
78 | |
79 | void registerClass(const std::string& className, AbstractFactory* pAbstractFactory) |
80 | /// Registers the instantiator for the given class with the DynamicFactory. |
81 | /// The DynamicFactory takes ownership of the instantiator and deletes |
82 | /// it when it's no longer used. |
83 | /// If the class has already been registered, an ExistsException is thrown |
84 | /// and the instantiator is deleted. |
85 | { |
86 | poco_check_ptr (pAbstractFactory); |
87 | |
88 | FastMutex::ScopedLock lock(_mutex); |
89 | |
90 | std::unique_ptr<AbstractFactory> ptr(pAbstractFactory); |
91 | typename FactoryMap::iterator it = _map.find(className); |
92 | if (it == _map.end()) |
93 | _map[className] = ptr.release(); |
94 | else |
95 | throw ExistsException(className); |
96 | } |
97 | |
98 | void unregisterClass(const std::string& className) |
99 | /// Unregisters the given class and deletes the instantiator |
100 | /// for the class. |
101 | /// Throws a NotFoundException if the class has not been registered. |
102 | { |
103 | FastMutex::ScopedLock lock(_mutex); |
104 | |
105 | typename FactoryMap::iterator it = _map.find(className); |
106 | if (it != _map.end()) |
107 | { |
108 | delete it->second; |
109 | _map.erase(it); |
110 | } |
111 | else throw NotFoundException(className); |
112 | } |
113 | |
114 | bool isClass(const std::string& className) const |
115 | /// Returns true iff the given class has been registered. |
116 | { |
117 | FastMutex::ScopedLock lock(_mutex); |
118 | |
119 | return _map.find(className) != _map.end(); |
120 | } |
121 | |
122 | private: |
123 | DynamicFactory(const DynamicFactory&); |
124 | DynamicFactory& operator = (const DynamicFactory&); |
125 | |
126 | typedef std::map<std::string, AbstractFactory*> FactoryMap; |
127 | |
128 | FactoryMap _map; |
129 | mutable FastMutex _mutex; |
130 | }; |
131 | |
132 | |
133 | } // namespace Poco |
134 | |
135 | |
136 | #endif // Foundation_DynamicFactory_INCLUDED |
137 | |