内存管理3@Property参数

Car.h:

#import <Foundation/Foundation.h>

@interface Card : NSObject

@end

#import "Card.h"

@implementation Card
-(void)dealloc{
    NSLog(@"Card被销毁");
    [super dealloc];
}
@end

#import <Foundation/Foundation.h>

@interface Book : NSObject

@end

#import "Book.h"

@implementation Book

-(void)dealloc{
    NSLog(@"Book被销毁了");
}

@end

#import <Foundation/Foundation.h>
@class Book;
@class Card;

@interface Student : NSObject{
    Book *_book;
}
//retain参数相当于.m中的setCard中的一大坨,nonatomic参数相当于set，get方法不需要枷锁，不需要线程保护，提高效率，一般都加nonatomic属性，以提高性能
@property(nonatomic,retain) Book *book;
//retain参数相当于.m中的setCard中的一大坨
@property(retain) Card *card;
//readonly是具有只读属性 还有readwrite属性
@property(readwrite) int age;

//属性默认就是atomic属性，能够提供给多个线程调用，get和set方法进行枷锁，保证线程安全
@property(atomic) int no;
//getter实现了方法名
@property(nonatomic,getter = isRich) BOOL rich;
@end

#import "Student.h"
#import "Book.h"

@implementation Student
//-(void)setBook:(Book *)book{
//    if(_book!=book)
//    {
//        [_book release];
//         _book=[_book retain];
//        
//    }
//}

//setCard相当于.h之前@property（retain）参数 自动实现
//-(void)setCard:(Card *)card{
//    if(_card!=card)
//    {
//        [_card release];
//        _card=[_card retain];
//    }
//}

//getf方法可以由系统自动帮助实现
//-(Book *)book{
//    return _book;
//}
-(void)dealloc{
    NSLog(@"Student被销毁");
    [_book release];
    [_card release];
    [super dealloc];
}
@end

#import <Foundation/Foundation.h>
#import "Student.h"
#import "Book.h"
#import "Card.h"

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        
        Student *student =[[Student alloc] init];
        Book *book=[[Book alloc] init];
        student.book=book;
        //student.rich=YES;
        //BOOL _rich=student.isRich;//前面Student.h中实现了getter方法名
        
        Card *card=[[Card alloc] init];
        [card release];
        [book release];
        [student release];
    }
    return 0;
}

2013-08-02 15:03:12.496 内存管理3 @property参数[871:303] Card被销毁

2013-08-02 15:03:12.498 内存管理3 @property参数[871:303] Student被销毁

2013-08-02 15:03:12.499 内存管理3 @property参数[871:303] Book被销毁了