gistfile1.m

@interface Class ()

@property (nonatomic, readonly) NSDateFormatter *dateFormatter;

@end


@implementation Class

@synthesize dateFormatter;

- (NSDateFormatter*)dateFormatter {
    if(dateFormatter == nil)
        dateFormatter = [[NSDateFormatter alloc] init];
    return dateFormatter;
}

- (void)someMethod {
    NSDate *date [self.dateFormatter dateFromString:someString];
}