Does @property(retain) need a release?

Question

Below are three fragments of code, the first two are interfaces for two objects along with a couple of @property commands. Please note that this is just me learning, its not part of an application just a small test program.

After adding (retain) to the 2nd @property I noticed that my machine object was leaking when my program exited, what I did to fix this was add a release in the Artist objects dealloc, does this sound right?

@interface Machine : NSObject
{
    NSString *name;
    NSString *type;
    NSString *os;
}

@interface Artist : NSObject
{
    NSString *name;
    Machine *system;
}
@property(copy) NSString *name;
@property(retain) Machine *system;
@end

// DEALLOC IN @implementation Artist
-(void)dealloc {
    NSLog(@"_deal: %@", self);
    [system release];
    [super dealloc];
}

gary

Answer 1

you must call release by hands for each time you've called retain or alloc method.

Answer 2

Yes, by setting it to nil or calling release depending on OS.

Answer 3

If you are targeting Mac OS X, the best answer would be to turn on garbage collection and delete the -dealloc method.

To answer the specific question, you need to release both name and system in your -dealloc method.