[squeak-dev] WeakRegistry>>remove: - when you'll be in trouble
Igor Stasenko
siguctua at gmail.com
Sun Oct 10 12:59:14 UTC 2010
A current implementation of this method
remove: oldObject ifAbsent: exceptionBlock
"Remove oldObject as one of the receiver's elements."
oldObject ifNil: [ ^nil ].
^(self protected: [ valueDictionary removeKey: oldObject ifAbsent: nil ])
ifNil: [ exceptionBlock value ]
simply removes a previously registered object from registry and voila.
Now lets get back to our discussion about multiple finalizers per
object and using them in weak subscriptions etc.
Suppose i am added a socket to weak registry,
and suppose i am added a weak subscription to it.
Now, if i do 'socket close' , it tells weak registry to remove it from list.
And what we'll have:
- socket handle is closed
- socket is wiped from weak registry
- but weak subscription still listed somewhere in a list of subscriptions
My suggestion is, that upon #remove:,
a weak registry should notify all executors that object of interest
are no longer takes part in finalization scheme,
so they should not count on receiving #finalize eventually.
In other words:
remove: oldObject ifAbsent: exceptionBlock
"Remove oldObject as one of the receiver's elements."
oldObject ifNil: [ ^nil ].
^(self protected: [ | executor |
executor := valueDictionary removeKey: oldObject ifAbsent: nil.
executor discardFinalization.
])
ifNil: [ exceptionBlock value ]
--
Best regards,
Igor Stasenko AKA sig.
More information about the Squeak-dev
mailing list
|