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

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  19
  20
  21
  22  module com {  module sun {  module star {  module uno {
  23
  24 /** the server-side interface to a weak object.
  25
  26
  27
  28     <p>This interface is proxy to the adapted object.
  29     In order to make it possible to have weak references to objects,
  30     the XAdapter interface must be implemented to provide
  31     a weak adapter for the clients.
  32
  33     <h4>Concept of weak referencing:</h4>
  34
  35     </p>
  36     <p>This module specifies the interfaces for implementing and using
  37     weak references.</p>
  38     <p>
  39
  40     </p>
  41     <p>The sense of weak references is to hold a reference to an object
  42     without affecting the lifetime of the object. That means that a weak
  43     reference may become invalid, at any time, if the referenced object dies.
  44
  45     </p>
  46     <p>The following interfaces describe one way to handle weak references
  47     by providing a weak adapter. The weak object has to provide this
  48     adapter if anyone wants to hold a weak reference. To separate their
  49     lifetimes, the adapter and the original object must not share the same
  50     reference counter.  The weak reference is in fact only a hard reference
  51     to the adapter, which knows - but does not hold - the original object.
  52     That means that the implementation and synchronization of weak
  53     referencing is the responsibility of the object.  The following
  54     interfaces are involved in the concept of weak referencing:
  55
  56     <dl>
  57     <dt>
  58     XWeak
  59     </dt>
  60     <dd>is the server-side interface of the referred object. This
  61     referred object must support the XAdapter interface.
  62
  63     </dd>
  64     <dt>
  65     XReference
  66     </dt>
  67     <dd>is a client-side interface which must be implemented by
  68     the holder of any weak reference. It is used for notification
  69     when the adapted object dies.
  70
  71     </dd>
  72     </dl>
  73     </p>
  74  */
  75 published interface XWeak: com::sun::star::uno::XInterface
  76 {
  77     /** queries the weak adapter.
  78
  79
  80
  81         <p>It is important that the adapter must know, but not hold
  82         the adapted object. If the adapted object dies, all references
  83         to the adapter have to be notified to release the adapter.
  84
  85         </p>
  86      */
  87     com::sun::star::uno::XAdapter queryAdapter();
  88
  89 };
  90
  91
  92 }; }; }; };
  93
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