IOS9 New Keywords Nullable, nonnull, Null_unspecified, null_resettable

#import "ViewController.h"@interfaceViewcontroller () @property (nonatomic,nullable) NSString*name;//can be empty@property (nonatomic,nonnull) Nsstring*password;//cannot be empty@property (nonatomic,null_unspecified) nsstring*unkonw;//Unknown type@property (nonatomic) NSString* _nullable name1;//can be empty@property (nonatomic) nsstring* _nonnull Password1;//cannot be empty@property (nonatomic) nsstring* _null_unspecified UNKONW1;//Unknown type@property (nonatomic) NSString* __nullable name2;//can be empty@property (nonatomic) nsstring* __nonnull password2;//cannot be empty@property (nonatomic) nsstring* __null_unspecified unkonw2;//Unknown type@property (nonatomic,null_resettable) NSString*SETSTR;//The Get method cannot be empty, and the set method can be null-(void) Creatdemowithname: (Nullable nsstring*) name PSW: ( nsstring* _nonnull) PSW unkonwstr: (null_unspecified nsstring*) Unkownstr;@end@implementationViewcontroller- (void) viewdidload {[Super viewdidload]; [Self creatdemowithname:nil PSW:@"Heheheh"Unkonwstr:nil]; }-(void) Setsetstr: (NSString *) setstr{Self.setstr=@"hehehe"; }-(void) Creatdemowithname: (Nullable nsstring*) name PSW: ( nsstring* _nonnull) PSW unkonwstr: (null_unspecified nsstring*) unkownstr{NSLog (@"%@=%@=%@", NAME,PSW,UNKOWNSTR);}

IOS9 New Keywords Nullable, nonnull, Null_unspecified, null_resettable