NSMutableArray arrayWithCapacity vs initWithCapacity

Question

I am new to iPhone / Objective-C with an extensive Java background.

I learn more about memory management in objective-c, and I read Apple's memory management documentation: http://developer.apple.com/iphone/library/documentation/Cocoa/Conceptual/MemoryMgmt/MemoryMgmt.html p>

The Object Ownership Policy section says that you own any object created using a method that begins by highlighting, new, or contains a copy. Ownership implies that you need an explicit releaseobject when you are done with it.

So, I look at the NSMutableArray documentation: http://developer.apple.com/mac/library/documentation/Cocoa/Reference/Foundation/Classes/NSMutableArray_Class/Reference/Reference.html

There are two methods that pretty much do the same thing: they create an array with some initial capacity. One of them is a class method, and the other is an instance method.

+ (id)arrayWithCapacity:(NSUInteger)numItems;
- (id)initWithCapacity:(NSUInteger)numItems;

Now, being a lazy Java developer, why did I ever choose an instance method over a class method, knowing that at some point in time I should clear myself after?

, ... , ? autorelease vs. release ? , (iPhone) , ?

!

Answer 1

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Answer 2

arrayWithCapacity: .

initWithCapacity: , . [[A alloc] init...], " ", , "alloc", "" "" . , , .

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,

Blah *blah = [Blah blahWithSomething];
[myMutableArray addObject:blah];

,

Blah *blah = [[Blah alloc] initWithSomething];
[myMutableArray addObject:blah];
[blah release];

. , , runloop, , / , runloop. , , , .

Answer 3

, , (== " " ):

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• ,