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Sean P. DeNigris

Finalization

Administrator

I found the following list threads...

http://forum.world.st/Finalization-question-td1300962.html mentions #beFinalizable, which doesn't seem to exist. I guess it was just an example, but seems like it should be added, no?

In http://forum.world.st/object-finalization-td3771196.html Igor suggested that the key is to do:
WeakRegistry default add: obj.

This guarantees? that #finalize will be called when the object is garbage collected.

I'm asking regarding my recent work wrapping the FMOD sound library with NativeBoost. I'm thinking my NBExternalObjects should release their resources when no longer referenced. I want to say:
FmodSound>>#finalize
self primReleaseSound: handle.

So I've pieced together that I would have to also write:
FmodSound>>new
instance := super new
whatever;
beFinalizable;
yourself.

Object>>#beFinalizable
WeakRegistry default add: self.

Am I correct that:
1. The above code would cause the resource to be safely released when the sound object was garbage collected?
2. This approach would be a good way to manage these types of resources?

Any hints would be appreciated as to the best way to accomplish managing these...

Thanks!

Cheers,
Sean

Igor Stasenko

Re: Finalization

On 29 November 2013 07:21, Sean P. DeNigris <[hidden email]> wrote:

I found the following list threads...

http://forum.world.st/Finalization-question-td1300962.html mentions
#beFinalizable, which doesn't seem to exist. I guess it was just an example,
but seems like it should be added, no?

In http://forum.world.st/object-finalization-td3771196.html Igor suggested
that the key is to do:
WeakRegistry default add: obj.

This guarantees? that #finalize will be called when the object is garbage
collected.

I'm asking regarding my recent work wrapping the FMOD sound library with
NativeBoost. I'm thinking my NBExternalObjects should release their
resources when no longer referenced. I want to say:
FmodSound>>#finalize
self primReleaseSound: handle.

So I've pieced together that I would have to also write:
FmodSound>>new
instance := super new
whatever;
beFinalizable;
yourself.

Object>>#beFinalizable
WeakRegistry default add: self.

Am I correct that:
1. The above code would cause the resource to be safely released when the
sound object was garbage collected?

yes

2. This approach would be a good way to manage these types of resources?

yes

Any hints would be appreciated as to the best way to accomplish managing
these...

See NBExternalResourceManager class comment

Thanks!

-----
Cheers,
Sean
--
View this message in context: http://forum.world.st/Finalization-tp4726046.html
Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

--
Best regards,
Igor Stasenko.

Sean P. DeNigris

Re: Finalization

Administrator

> #beFinalizable, which doesn't seem to exist. I guess it was just an example, but seems like it should be added, no?

Do you agree that #beFinalizable would be a nice addition? If so, I will open an issue...

Igor Stasenko wrote

> See NBExternalResourceManager class comment

So the point of using NBExternalResourceManager is that it adds session awareness to finalization so that one doesn't attempt to release invalid external resources from previous sessions, right?

I was also thinking that maybe FMOD should also have a shutDown: which collects all external resource objects and cleans them up. Does that sound like a good idea? Overkill?

Cheers,
Sean