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21 
22 
23 #ifndef _CPPUHELPER_WEAKAGG_HXX_
24 #define _CPPUHELPER_WEAKAGG_HXX_
25 
26 #include <cppuhelper/weak.hxx>
27 #include <com/sun/star/uno/XAggregation.hpp>
28 
29 
30 namespace cppu
31 {
32 
33 /** Base class to implement an UNO object supporting weak references, i.e. the object can be held
34     weakly (by a ::com::sun::star::uno::WeakReference) and aggregation, i.e. the object can be
35     aggregated by another (delegator).
36     This implementation copes with reference counting.  Upon last release(), the virtual dtor
37     is called.
38 
39     @derive
40     Inherit from this class and delegate acquire()/ release() calls.  Re-implement
41     XAggregation::queryInterface().
42 */
43 class OWeakAggObject
44 	: public ::cppu::OWeakObject
45 	, public ::com::sun::star::uno::XAggregation
46 {
47 public:
48 	/** Constructor.  No delegator set.
49     */
50 	inline OWeakAggObject() SAL_THROW( () )
51 		{}
52 
53 	/** If a delegator is set, then the delegators gets acquired.  Otherwise call is delegated to
54         base class ::cppu::OWeakObject.
55     */
56 	virtual void SAL_CALL acquire() throw();
57 	/** If a delegator is set, then the delegators gets released.  Otherwise call is delegated to
58         base class ::cppu::OWeakObject.
59     */
60 	virtual void SAL_CALL release() throw();
61 	/** If a delegator is set, then the delegator is queried for the demanded interface.  If the
62         delegator cannot provide the demanded interface, it calls queryAggregation() on its
63         aggregated objects.
64 
65         @param rType demanded interface type
66         @return demanded type or empty any
67         @see queryAggregation.
68     */
69 	virtual ::com::sun::star::uno::Any SAL_CALL queryInterface( const ::com::sun::star::uno::Type & rType )
70 		throw(::com::sun::star::uno::RuntimeException);
71 
72 	/** Set the delegator.  The delegator member reference is a weak reference.
73 
74         @param Delegator the object that delegate its queryInterface to this aggregate.
75     */
76 	virtual void SAL_CALL setDelegator( const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface > & Delegator )
77 		throw(::com::sun::star::uno::RuntimeException);
78 	/** Called by the delegator or queryInterface. Re-implement this method instead of
79         queryInterface.
80 
81         @see queryInterface
82     */
83 	virtual ::com::sun::star::uno::Any SAL_CALL queryAggregation( const ::com::sun::star::uno::Type & rType )
84 		throw(::com::sun::star::uno::RuntimeException);
85 
86 protected:
87 	/** Virtual dtor. Called when reference count is 0.
88 
89         @attention
90         Despite the fact that a RuntimeException is allowed to be thrown, you must not throw any
91         exception upon destruction!
92 	*/
93     virtual ~OWeakAggObject() SAL_THROW( (::com::sun::star::uno::RuntimeException) );
94 
95 	/** weak reference to delegator.
96 	*/
97 	::com::sun::star::uno::WeakReferenceHelper xDelegator;
98 private:
99     /** @internal */
100 	OWeakAggObject( const OWeakAggObject & rObj ) SAL_THROW( () );
101     /** @internal */
102     OWeakAggObject & operator = ( const OWeakAggObject & rObj ) SAL_THROW( () );
103 };
104 
105 }
106 
107 #endif
108