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[SteveMobs]

Hello,

by doing more and more Objective-C I somehow get more and more confused about memory management. I have read the according document but what I need are some best practice examples. Here I have a small example class and a couple of questions.

Are there any other helpful guides / documents explaining how to write custom classes?

@interface MyClass : NSObject {
	NSString *name;
	CoolObject *coolObject;
}

@property (readonly, retain) NSString *name;
@property (readwrite, retain) CoolObject *coolObject;

- (id)initWithName:(NSString *)theName;
- (void)doWhatever;

@end
@implementation MyClass

@synthesize name, coolObject;

// custom initializer
- (id)initWithName:(NSString *)theName {
	if (self = [super init]) {
		name = theName;
		coolObject = [[CoolObject alloc] init];
	}
	return self;
}

// overwrite setter
- (void)setName:(NSString *)theName {
	if (theName != nil && [theName length] > 0) {
		name = theName;
	}
}

// overwrite setter
- (void)setCoolObject:(CoolObject *)theObject {
	if (theObject != nil) {
		coolObject = theObject;
	}
}

- (void)doWhatever {
    self.coolObject = [[CoolObject alloc] init];
}

- (void)dealloc {
	[name release];
	[coolObject release];
	[super dealloc];
}
@end

1. should a NSString property be assigned, retained or copied? What are best practices? Or when should I chose which?

2. in the custom initializer:
Is there a leak assigning the object?
Would this be better?

CoolObject *tmp = [[CoolObject alloc] init];
coolObject = tmp;
[tmp release];

What about the method doWhatever? Does this leak an object?
should it rather be:

[coolObject release];
CoolObject *tmp = [[CoolObject alloc] init];
self.coolObject = tmp;
[tmp release];

3. overwritten setters: is there a call of [name release] / [coolObject release] missing before the assignment?

4. dealloc: is it correct that

coolObject = nil;

is similiar to

[coolObject release];
coolObject = nil;

Thanks!