is this correct re returning a date re memory management?

is this correct re returning a date re memory management?

The assumption here I have is I want to return a date back to the caller, but I don't want the caller to be able to be change the date and impact the method's date, hence I thought I would return a copy.

So the code in the method I have is:

- (NSDate*)dateForMyTest {
     return [[self.endDate copy] autorelease];
}

I was assuming I have to autorelease it so the caller doesn't have to, as they would开发者_StackOverflow not have called an init/copy/etc themselves.

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It may work, but creating a copy is not necessary. NSDate is immutable and cannot be edited later.

This should suffice...

- (NSDate*)dateForMyTest {
     return self.endDate;
}

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You are correct, as far as it goes. But note that NSDate is immutable, so there is really no reason not to just return self.endDate.

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Yes, that is correct. Because the method name didn't include init/copy/new, you should autorelease.

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The copy autorelease may be needed if the app is using nsoperations/threads, etc. But you may be already thread safer - or not: When you use

return self.endDate

any number of things could be happening, depending on how the property was set up. Was it

 @property (retain) endDate; 

, or the more common, faster and less thread safe

 @property (nonatomic, retain) endDate; 

It is as complicated as you like!

What's the difference between the atomic and nonatomic attributes?