udkapi/com/sun/star/uno/XWeak.idl

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  27 #ifndef __com_sun_star_uno_XWeak_idl__
  28 #define __com_sun_star_uno_XWeak_idl__
  29
  30 #ifndef __com_sun_star_uno_XInterface_idl__
  31 #include <com/sun/star/uno/XInterface.idl>
  32 #endif
  33
  34 #ifndef __com_sun_star_uno_XAdapter_idl__
  35 #include <com/sun/star/uno/XAdapter.idl>
  36 #endif
  37
  38
  39 //=============================================================================
  40
  41  module com {  module sun {  module star {  module uno {
  42
  43 //=============================================================================
  44
  45 // DocMerge from xml: interface com::sun::star::uno::XWeak
  46 /** the server-side interface to a weak object.
  47
  48
  49
  50     <p>This interface is proxy to the adapted object.
  51     In order to make it possible to have weak references to objects,
  52     the <type>XAdapter</type> interface must be implemented to provide
  53     a weak adapter for the clients.
  54
  55     <h4>Concept of weak referencing:</h4>
  56
  57     </p>
  58     <p>This module specifies the interfaces for implementing and using
  59     weak references.</p>
  60     <p>
  61
  62     </p>
  63     <p>The sense of weak references is to hold a reference to an object
  64     without affecting the lifetime of the object. That means that a weak
  65     reference may become invalid, at any time, if the referenced object dies.
  66
  67     </p>
  68     <p>The following interfaces describe one way to handle weak references
  69     by providing a weak adapter. The weak object has to provide this
  70     adapter if anyone wants to hold a weak reference. To separate their
  71     lifetimes, the adapter and the original object must not share the same
  72     reference counter.  The weak reference is in fact only a hard reference
  73     to the adapter, which knows - but does not hold - the original object.
  74     That means that the implementation and synchronization of weak
  75     referencing is the responsibility of the object.  The following
  76     interfaces are involved in the concept of weak referencing:
  77
  78     <dl>
  79     <dt>
  80     <type>XWeak</type>
  81     </dt>
  82     <dd>is the server-side interface of the referred object. This
  83     referred object must support the <type>XAdapter</type> interface.
  84
  85     </dd>
  86     <dt>
  87     <type>XReference</type>
  88     </dt>
  89     <dd>is a client-side interface which must be implemented by
  90     the holder of any weak reference. It is used for notification
  91     when the adapted object dies.
  92
  93     </dd>
  94     </dl>
  95     </p>
  96  */
  97 published interface XWeak: com::sun::star::uno::XInterface
  98 {
  99     //-------------------------------------------------------------------------
 100
 101     // DocMerge from xml: method com::sun::star::uno::XWeak::queryAdapter
 102     /** queries the weak adapter.
 103
 104
 105
 106         <p>It is important that the adapter must know, but not hold
 107         the adapted object. If the adapted object dies, all references
 108         to the adapter have to be notified to release the adapter.
 109
 110         </p>
 111      */
 112     com::sun::star::uno::XAdapter queryAdapter();
 113
 114 };
 115
 116 //=============================================================================
 117
 118 }; }; }; };
 119
 120 /*=============================================================================
 121
 122 =============================================================================*/
 123 #endif