| 1 | // |
| 2 | // Instantiator.h |
| 3 | // |
| 4 | // Library: Foundation |
| 5 | // Package: Core |
| 6 | // Module: Instantiator |
| 7 | // |
| 8 | // Definition of the Instantiator 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_Instantiator_INCLUDED |
| 18 | #define Foundation_Instantiator_INCLUDED |
| 19 | |
| 20 | |
| 21 | #include "Poco/Foundation.h" |
| 22 | |
| 23 | |
| 24 | namespace Poco { |
| 25 | |
| 26 | |
| 27 | template <class Base> |
| 28 | class AbstractInstantiator |
| 29 | /// The common base class for all Instantiator instantiations. |
| 30 | /// Used by DynamicFactory. |
| 31 | { |
| 32 | public: |
| 33 | AbstractInstantiator() |
| 34 | /// Creates the AbstractInstantiator. |
| 35 | { |
| 36 | } |
| 37 | |
| 38 | virtual ~AbstractInstantiator() |
| 39 | /// Destroys the AbstractInstantiator. |
| 40 | { |
| 41 | } |
| 42 | |
| 43 | virtual Base* createInstance() const = 0; |
| 44 | /// Creates an instance of a concrete subclass of Base. |
| 45 | |
| 46 | private: |
| 47 | AbstractInstantiator(const AbstractInstantiator&); |
| 48 | AbstractInstantiator& operator = (const AbstractInstantiator&); |
| 49 | }; |
| 50 | |
| 51 | |
| 52 | template <class C, class Base> |
| 53 | class Instantiator: public AbstractInstantiator<Base> |
| 54 | /// A template class for the easy instantiation of |
| 55 | /// instantiators. |
| 56 | /// |
| 57 | /// For the Instantiator to work, the class of which |
| 58 | /// instances are to be instantiated must have a no-argument |
| 59 | /// constructor. |
| 60 | { |
| 61 | public: |
| 62 | Instantiator() |
| 63 | /// Creates the Instantiator. |
| 64 | { |
| 65 | } |
| 66 | |
| 67 | virtual ~Instantiator() |
| 68 | /// Destroys the Instantiator. |
| 69 | { |
| 70 | } |
| 71 | |
| 72 | Base* createInstance() const |
| 73 | { |
| 74 | return new C; |
| 75 | } |
| 76 | }; |
| 77 | |
| 78 | |
| 79 | } // namespace Poco |
| 80 | |
| 81 | |
| 82 | #endif // Foundation_Instantiator_INCLUDED |
| 83 | |