oc54--auatorelease应用场景

//
//  Person.h
 
#import <Foundation/Foundation.h>
 
@interface Person : NSObject
 
@property (nonatomic, assign) int age;
 
+ (instancetype)person;
 
- (instancetype)initWithAge:(int)age;
 
+ (instancetype)personWithAge:(int)age;
@end

//  Person.m
 
#import "Person.h"
 
@implementation Person
 
//提供构造方法的时候也要提供类工厂方法(API里面是这么写的)，如果是MRC还要提供antorelease.
 
+ (instancetype)person  //类工厂方法
{
    return [[[self alloc] init] autorelease];
}
 
- (instancetype)initWithAge:(int)age{ //构造方法
    if (self = [super init]) {
        _age = age;
    }
    return self;
}
 
+ (instancetype)personWithAge:(int)age //类工厂方法
{
    /*
    Person *p = [[self alloc] init];
    p.age = age;
    return [p autorelease];
    */
    return [[[self alloc] initWithAge:age] autorelease];  //self = Person；
}
 
- (void)dealloc
{
    NSLog(@"%s", __func__);
    [super dealloc];
}
@end

//
//  main.m
//  auatorelease应用场景
 
#import <Foundation/Foundation.h>
#import "Person.h"
 
int main(int argc, const char * argv[]) {
 
    @autoreleasepool {
 
        Person *p = [[[Person alloc] init] autorelease];
        p.age = ;
        NSLog(@"age = %i", p.age);
 
        Person *p1 = [[[Person alloc] init] autorelease];
 
        Person *p2 = [[[Person alloc] init] autorelease];
 
        Person *1p = [Person person];
        1p.age = ;
        NSLog(@"age = %i", 1p.age);
 
         // 注意: Foundation框架的类, 但凡是通过类工厂方法创建的对象都是autorelease的
        [[NSString alloc] init];
        [NSString string];
 
//        [NSString alloc] initWithString:(NSString *)
//        [NSString stringWithString:(NSString *)];
 
        Person *p = [[[Person alloc] initWithAge:] autorelease];
        NSLog(@"age = %i", p.age);
 
        Person *p = [Person personWithAge:];
        NSLog(@"age = %i", p.age);
 
    }
    return ;
}