1
- (void)logSubClassChain:(Class)cls {
2
    int count = objc_getClassList(NULL, 0);
3

4
    NSMutableArray *tempArr = @[cls].mutableCopy;
5
    Class *classes = (Class*)malloc(sizeof(Class) * count);
6
    objc_getClassList(classes, count);
7
    for (int i = 0; i < count; i++) {
8
        if (cls == class_getSuperclass(classes[i])) {
9
            [tempArr addObject:classes[i]];
10
        }
11
    }
12
    free(classes);
13
    NSLog(@"Classes : %@", tempArr);
14
}

1
+ (void)logAllMethodOf:(Class)cls {
2
    NSLog(@"%s %@", __func__, cls);
3
    unsigned int count = 0;
4
    Method *methodList = class_copyMethodList(cls, &count);
5
    for (int i = 0; i < count; i++) {
6
        Method method = methodList[i];
7
        SEL sel = method_getName(method);
8
        IMP imp = method_getImplementation(method);
9
        NSLog(@"SEL: %@ IMP: %p", NSStringFromSelector(sel), imp);
10
    }
11
    free(methodList);
12
    NSLog(@"\n");
13
}

1
@implementation RYSubModel
2

3
- (void)setBooks:(NSMutableArray<NSString *> *)books {
4
    [super setBooks:books];
5
}
6

7
@end

1
// 子类
2
+[KVOTool logAllMethodOf:] RYSubModel
3
SEL: setBooks: IMP: 0x100003240
4

5
// 本类
6
添加观察者之前：RYModel
7
+[KVOTool logAllMethodOf:] RYModel
8
SEL: name IMP: 0x100003160
9
SEL: .cxx_destruct IMP: 0x1000031f0
10
SEL: setName: IMP: 0x1000030c0
11
SEL: books IMP: 0x100003190
12
SEL: setBooks: IMP: 0x1000031b0
13

14
// 中间类
15
添加观察者之后：NSKVONotifying_RYModel
16
+[KVOTool logAllMethodOf:] NSKVONotifying_RYModel
17
SEL: setBooks: IMP: 0x7fff212b9d2e
18
SEL: setName: IMP: 0x7fff212b9d2e
19
SEL: class IMP: 0x7fff2127cc06
20
SEL: dealloc IMP: 0x7fff212bf9f5
21
SEL: _isKVOA IMP: 0x7fff213e3e3a

1
+ (BOOL)automaticallyNotifiesObserversForKey:(NSString *)key {
2
    if ([key isEqualToString:@"name"]) {
3
        return NO;
4
    }
5
    return YES;
6
}