xref: /aoo41x/main/udkapi/com/sun/star/uno/XWeak.idl (revision 408a4873)

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#ifndef __com_sun_star_uno_XWeak_idl__
#define __com_sun_star_uno_XWeak_idl__

#ifndef __com_sun_star_uno_XInterface_idl__
#include <com/sun/star/uno/XInterface.idl>
#endif

#ifndef __com_sun_star_uno_XAdapter_idl__
#include <com/sun/star/uno/XAdapter.idl>
#endif


//=============================================================================

 module com {  module sun {  module star {  module uno {

//=============================================================================

// DocMerge from xml: interface com::sun::star::uno::XWeak
/** the server-side interface to a weak object.



	<p>This interface is proxy to the adapted object.
	In order to make it possible to have weak references to objects,
	the <type>XAdapter</type> interface must be implemented to provide
	a weak adapter for the clients.

	<h4>Concept of weak referencing:</h4>

	</p>
	<p>This module specifies the interfaces for implementing and using
	weak references.</p>
	<p>

	</p>
	<p>The sense of weak references is to hold a reference to an object
	without affecting the lifetime of the object. That means that a weak
	reference may become invalid, at any time, if the referenced object dies.

	</p>
	<p>The following interfaces describe one way to handle weak references
	by providing a weak adapter. The weak object has to provide this
	adapter if anyone wants to hold a weak reference. To separate their
	lifetimes, the adapter and the original object must not share the same
	reference counter.  The weak reference is in fact only a hard reference
	to the adapter, which knows - but does not hold - the original object.
	That means that the implementation and synchronization of weak
	referencing is the responsibility of the object.  The following
	interfaces are involved in the concept of weak referencing:

	<dl>
	<dt>
	<type>XWeak</type>
	</dt>
	<dd>is the server-side interface of the referred object. This
	referred object must support the <type>XAdapter</type> interface.

	</dd>
	<dt>
	<type>XReference</type>
	</dt>
	<dd>is a client-side interface which must be implemented by
	the holder of any weak reference. It is used for notification
	when the adapted object dies.

	</dd>
	</dl>
	</p>
 */
published interface XWeak: com::sun::star::uno::XInterface
{
	//-------------------------------------------------------------------------

	// DocMerge from xml: method com::sun::star::uno::XWeak::queryAdapter
	/** queries the weak adapter.



		<p>It is important that the adapter must know, but not hold
		the adapted object. If the adapted object dies, all references
		to the adapter have to be notified to release the adapter.

		</p>
	 */
	com::sun::star::uno::XAdapter queryAdapter();

};

//=============================================================================

}; }; }; };

/*=============================================================================

=============================================================================*/
#endif