1 //
 2 //  YYSharedModelTool.h
 3 //  SharedModel
 4 //
 5 //  Created by Arvin on 15/12/21.
 6 //  Copyright © 2015年 Arvin. All rights reserved.
 7 //
 8 
 9 #ifndef YYSharedModelTool_h
10 #define YYSharedModelTool_h
11 
12 // .h 文件
13 // ##: 在宏中,表示拼接前后字符串
14 #define YYSharedModelTool_H(className) + (instancetype)shared##className;
15 
16 #if __has_feature(objc_arc) // ARC 环境
17 
18 // .m 文件
19 #define YYSharedModelTool_M(className)\
20     /****ARC 环境下实现单例的方法****/\
21     + (instancetype)shared##className {\
22         return [[self alloc] init];\
23     }\
24     \
25     - (id)copyWithZone:(nullable NSZone *)zone {\
26         return self;\
27     }\
28     \
29     + (instancetype)allocWithZone:(struct _NSZone *)zone {\
30         static id instance;\
31         static dispatch_once_t onceToken;\
32         dispatch_once(&onceToken, ^{\
33             instance = [super allocWithZone:zone];\
34         });\
35         return instance;\
36     }
37 
38 #else // MRC 环境
39 
40 // .m 文件
41 #define YYSharedModelTool_M(className)\
42     \
43     + (instancetype)shared##className {\
44         return [[self alloc] init];\
45     }\
46     \
47     - (id)copyWithZone:(nullable NSZone *)zone {\
48         return self;\
49     }\
50     \
51     + (instancetype)allocWithZone:(struct _NSZone *)zone {\
52         static id instance;\
53         static dispatch_once_t onceToken;\
54         dispatch_once(&onceToken, ^{\
55             instance = [super allocWithZone:zone];\
56         });\
57         return instance;\
58     }\
59     /****MRC 环境需要重写下面3个方法****/\
60     - (oneway void)release {\
61     \
62     }\
63     - (instancetype)retain {\
64         return self;\
65     }\
66     - (instancetype)autorelease {\
67         return self;\
68     }
69 
70 #endif
71 
72 #endif /* YYSharedModelTool_h */