代理模式

定义

代理模式(Proxy),为其他对象提供一种代理以控制对这个对象的访问.

使用场景

1.远程代理,也就是为一个对象在不同的地址空间提供局部代表.这样可以隐藏一个对象存在于不同地址空间的事实.

2.虚拟代理,是根据需要创建开销很大的对象.通过它来存放实例化需要很长时间的真实对象.

3.安全代理,用来控制真实对象访问的权限.

4.智能指引,是指当调用真实的对象时,代理处理另外一些事.

实现代码

//  SchoolGirl.h
#import <Foundation/Foundation.h>
@interface SchoolGirl :
NSObject
@property (nonatomic,copy)
NSString *name;
@end
//  SchoolGirl.m
#import "SchoolGirl.h"
@implementation SchoolGirl
@end
//  Pursuit.h
#import "GiveGift.h"
@class SchoolGirl;
@interface Pursuit : GiveGift
@property (nonatomic,copy) SchoolGirl *girl;
@end
//  Pursuit.m
#import "Pursuit.h"
#import "SchoolGirl.h"
@implementation Pursuit
-(void)giveDolls:(SchoolGirl *)schoolGirl
{
    NSLog(@"%@送你洋娃娃",schoolGirl.name);
}
-(void)giveFlowers:(SchoolGirl *)schoolGirl
{
    NSLog(@"%@送你花",schoolGirl.name);
}
-(void)giveChocolate:(SchoolGirl *)schoolGirl
{
    NSLog(@"%@送你巧克力",schoolGirl.name);
}
@end
//  GiveGift.h
#import <Foundation/Foundation.h>
@class SchoolGirl;
@interface GiveGift :
NSObject
-(void)giveDolls:(SchoolGirl *)schoolGirl;
-(void)giveFlowers:(SchoolGirl *)schoolGirl;
-(void)giveChocolate:(SchoolGirl *)schoolGirl;
@end
//  GiveGift.m
#import "GiveGift.h"
@implementation GiveGift
@end
//  Proxy.h
#import "GiveGift.h"
@class Pursuit;
@interface Proxy :
GiveGift
@property (nonatomic,copy)
Pursuit *pursuit;
@end
//  Proxy.m
#import "Proxy.h"
#import "Pursuit.h"
#import "SchoolGirl.h"
@implementation Proxy
-(void)giveDolls:(SchoolGirl *)schoolGirl
{
    Pursuit *pursuit = [[Pursuitalloc]
init];
    [pursuit giveDolls:schoolGirl];
}
-(void)giveFlowers:(SchoolGirl *)schoolGirl
{
    Pursuit *pursuit = [[Pursuitalloc]
init];
    [pursuit giveFlowers:schoolGirl];
}
-(void)giveChocolate:(SchoolGirl *)schoolGirl
{
    Pursuit *pursuit = [[Pursuitalloc]
init];
    [pursuit giveChocolate:schoolGirl];
}
@end

//  main.m
//  代理模式(Proxy),为其他对象提供一种代理以控制对这个对象的访问.
#import <Foundation/Foundation.h>
#import "SchoolGirl.h"
#import "Proxy.h"
int main(int argc,const
char * argv[]) {
    @autoreleasepool {
        SchoolGirl *jiaojiao = [[SchoolGirlalloc]
init];
        jiaojiao.name =@"jiaojiao";
        
        Proxy *proxy = [[Proxyalloc]
init];
        
        [proxy giveDolls:jiaojiao];
        [proxy giveFlowers:jiaojiao];
        [proxy giveChocolate:jiaojiao];
    }
    return0;
}