且构网

分享程序员开发的那些事...
且构网 - 分享程序员编程开发的那些事

oc48--多个对象内存管理练习

更新时间:2022-09-21 18:40:11

oc48--多个对象内存管理练习
//
//  main.m
//  多个对象内存管理练习
//
//  ARC是Xcode帮我们生成内存释放的代码,MRC是需要我买自己写retain和release。想研究内存管理只能在MRC,管理对象就是在管理引用计数器,计数器为0对象就释放。
//  给空指针发消息不会报错,给野指针发消息就会报错。
//  对象与对象之间有关系时候就用retain。

#import <Foundation/Foundation.h>
#import "Status.h"

int main(int argc, const char * argv[]) {
    /*
     模拟场景:
     * 老王在2010-1-1 17:56:34注册了一个账号
     (名称:xiaomage@520it.com, 密码:haomage)
     * 老王的生日是1986-3-8 18:18:18
     * 老王发布一条说说
     * 文字内容  @“爆米花手机比逼格更有逼格”
     * 图片 @“phone.png”
     * 发表时间: 2015-6-20 10:23:23
     * 作者: 老王
     * 被转发的说说: 没有
     * 评论数: 100
     * 转发数: 90
     * 点赞数: 200
     
     * 王大锤在2012-8-8 19:26:54注册了一个账号
     (名称:dachuimeimei@520it.com, 密码:654321)
     
     * 王大锤的生日是1989-9-6 14:16:28
     
     * 王大锤在2015-6-21 20:47:09时,转发了老王之前发布的说说, 并且还附带了一句话:@“真的很有逼格”
     */
    
    /*
     至少应该有三个类:
     账号类(Account):
       注册的时间(registerTime)
       账号(email)
       密码(pwd)
     用户类(Author):
       用户昵称(name)
       用户头像(icon)
       用户是否是会员(vip)
       用户对应的账号(account)
       用户的生日(birthday)
     微博类(Status):
       微博正文(text)
       微博配图(picture)
       微博发布的时间(createTime)
       微博对应的作者(用户)(author)
       评论数(commentCount)
       转发数(retweetCount)
       赞数(likeCount)
       转发微博(repostStatus)
     微博中有用户, 用户中有账号
     1.账号 2.用户 3.微博
    */
    
    // 1.给老王创建账号
    Account *lwAccount = [[Account alloc] init];
    lwAccount.email = @"xiaomage@520it.com";
    lwAccount.pwd = @"haomage";
    lwAccount.registerTime = (MyDate){2010, 1, 1, 17, 56, 34};
    
    // 2.根据账号设置用户信息
    Author *lwAuthor = [[Author alloc] init];
    lwAuthor.name = @"老王";
    lwAuthor.icon = @"lw.png";
    lwAuthor.vip = YES;
    lwAuthor.account = lwAccount;
    lwAuthor.birthday = (MyDate){1986, 3, 8, 18, 18, 18};
    
    // 3.发布微博
    Status *lwStatus = [[Status alloc] init];
    lwStatus.text = @"爆米花手机比逼格更有逼格";
    lwStatus.picture = @"phone.png";
    lwStatus.createTime = (MyDate){2015, 6, 20, 10, 23, 23};
    lwStatus.author = lwAuthor;
    lwStatus.commentCount = 100;
    lwStatus.retweetCount = 90;
    lwStatus.likeCount = 200;
    
    // 1.给王大锤创建账号
    Account *dcAccount = [[Account alloc] init];
    dcAccount.email = @"dachuimeimei@520it.com";
    dcAccount.pwd = @"654321";
    dcAccount.registerTime = (MyDate){2012, 8, 8, 19, 26, 54};
    
    // 2.根据账号设置用户信息
    Author *dcAuthor = [[Author alloc] init];
    dcAuthor.name = @"王大锤";
    dcAuthor.icon = @"wdc.png";
    dcAuthor.vip = NO;
    dcAuthor.account = dcAccount;
    dcAuthor.birthday = (MyDate){1989, 9, 6, 14, 16, 28};

    // 3.发布微博
    Status *dcStatus = [[Status alloc] init];
    dcStatus.text = @"真的很有逼格";
    dcStatus.picture = nil;
    dcStatus.createTime = (MyDate){2015, 6, 21, 20, 47, 9};
    dcStatus.author = dcAuthor;
    dcStatus.commentCount = 0;
    dcStatus.retweetCount = 0;
    dcStatus.likeCount = 0;
    dcStatus.repostStatus = lwStatus;
    
    [lwAccount release];
    [lwAuthor release];
    [lwStatus release];
    
    [dcAccount release];
    [dcAuthor release];
    [dcStatus release];
    
    return 0;
}
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//  Status.h

#import <Foundation/Foundation.h>
#import "Author.h"

@interface Status : NSObject

@property(nonatomic, retain)NSString *text;

@property(nonatomic, retain)NSString *picture;

@property(nonatomic, assign)MyDate createTime; //结构体诗基本数据类型

@property(nonatomic, retain)Author *author;

@property(nonatomic, assign)int commentCount;

@property (nonatomic, assign) int retweetCount;

@property(nonatomic, assign)int likeCount;

@property(nonatomic, retain)Status *repostStatus;
@end
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//
//  Status.m

#import "Status.h"

@implementation Status

- (void)dealloc
{
    NSLog(@"%s", __func__);
    
    /*
    [_text release];
    _text = nil;    //释放完了之后要致为空
    
    [_picture release];
    _picture = nil;
    
    [_author release];
    _author = nil;
    
    [_repostStatus release];
    _repostStatus = nil;
     */
    
    // 由于加了retain,下面点语法相当于调用了set方法:先release旧值, 然后再将新值赋值给属性
    self.text = nil;
    self.picture = nil;
    self.author = nil;
    self.repostStatus = nil;
    
    [super dealloc];
}

/*
 self.text = nil:
 - (void)setText:(NSString *)text // nil
 {
 // 加入上一次的值是@"abc";
 
 if (_text != text) {
 [_text release];//release旧值
 _text = [text retain]; // 新值加1后赋值过来,_text = nil;
 }
 }*/

@end
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//
//  Author.h

#import <Foundation/Foundation.h>
#import "Account.h"

@interface Author : NSObject

@property(nonatomic, retain)NSString *name;

@property(nonatomic, retain)NSString *icon;

@property(nonatomic, assign, getter=isVip)BOOL vip;

@property(nonatomic, retain)Account *account;

@property(nonatomic, assign)MyDate birthday;
@end
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//
//  Author.m

#import "Author.h"

@implementation Author

- (void)dealloc
{
    NSLog(@"%s", __func__);
    [_name release];
    [_icon release];
    [_account release];
    [super dealloc];
}
@end
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//  Account.h

#import <Foundation/Foundation.h>

typedef struct{
    int year;
    int month;
    int day;
    int hour;
    int minute;
    int second;
} MyDate;
@interface Account : NSObject

@property(nonatomic, assign)MyDate registerTime;

@property(nonatomic, retain)NSString *email; // copy

@property(nonatomic, retain)NSString *pwd;
@end
oc48--多个对象内存管理练习
oc48--多个对象内存管理练习
//
//  Account.m


#import "Account.h"

@implementation Account

-(void)dealloc
{
    NSLog(@"%s", __func__);
    [_email release];
    [_pwd release];
    [super dealloc];
}
@end
oc48--多个对象内存管理练习

 


本文转自农夫山泉别墅博客园博客,原文链接:http://www.cnblogs.com/yaowen/p/7428050.html,如需转载请自行联系原作者