First version gives the object no chance to disagree with that (e.g. if a
process is still running and can't be cancelled realy). Last version
provides this possibility, but can't guarantee real termination of called object.
It depends from the environment of an object, if one or both mechanism are neccessary.
Base interface XCloseBroadcaster makes it possible that any listener
which is interrested on life time of listened object ...
Must definitly be called before ::com::sun::star::lang::XComponent::dispose().
But nobody can guarentee real closing of called object - because it can disagree with that if any
still running processes can't be cancelled yet. It's not allowed to block this call till internal
operations will be finished here. They must be cancelled or call must return imediatly by throwing
the CloseVetoException. Otherwise (if nothing exist to disagree) it must return normaly.
Before any internal processes will be cancelled, all registered XCloseListener
must be notified. Any of them can disagree with a CloseVetoException too.
It's forbidden to catch this exception inside the called close() method because the caller must
get this information!
If somewhere disagree with a CloseVetoException it will not clear who has to close the object again
after still running processes was finished. The parameter DeliverOwnership regulate that.
If it is set to false the caller of the method close() will be the owner of this object in every case.
Then it's not allowed to call close() from any other place (may a registered XCloseListener).
If it is set to true the caller gives up his ownership. If a XCloseListener throw the veto exception
he will be the new owner of the closing object. This information is passed to the listener by a parameter of
his notification method XCloseListener::queryClosing(). After his operations was finished
he MUST try to close it again. If the closing object itselfs disagree by an exception and the parameter
DeliverOwnership was set to true the object will be his own owner with all consequences of that.
Note:
There is no way to get the ownership back if it was delivered!
If this method was already called on an object it should return without any reaction. Normaly it's possible to throw
a ::com::sun::star::lang::DisposedException for already disposed or closed objects
(which represent a ::com::sun::star::uno::RuntimeException and can be thrown by every interface call),
but it shouldn't be used here. The veto exception should be the only way to indicates the result.
Parameter DeliverOwnership
true delegates the ownership of ths closing object to any one which throw the CloseVetoException.
This new owner has to close the closing object again if his still running processes will be finished.
false let the ownership at the original one which called the close() method. He must react for possible
CloseVetoExceptions and try it again at a later time. This can be usefull for a generic UI handling.
Throws
CloseVetoException
indicates that the closing object himself or any of his currently registered listener disagree with this close() request.