Novice questions about issues of Exception

posts by z550946941 on 2012-12-20 16:33:01 Edit

This is a book about Objective-c example, using CodeBlocks compile and run, the following error:
Uncaught exception NSInvalidArgumentException, reason: NSAutoreleasePool (instance) does not recognize length
You look great God and what is wrong with
Code is as follows:

 
# Import  

/ / ---------------------------------------- 
@ Interface Tire: NSObject 
@ End / / Tire 

@ Implementation Tire 
- (NSString *) description {
return (@ "I am a tire. I last a while."); 
} / / Description 
@ End / / Tire 

/ / ---------------------------------------- 
@ Interface AllWeatherRadial: Tire 
@ End / / AllWeatherRadial 

@ Implementation AllWeatherRadial 
- (NSString *) description {
return (@ "i am a tire for rain or shine."); 
} 
@ End 

/ / ---------------------------------------- 
@ Interface Engine: NSObject 
@ End / / Engine 

@ Implementation Engine 
- (NSString *) description {
return (@ "I am an engine, Vrooom!"); 
} / / Description 
@ End / / Engine 

/ / ---------------------------------------- 
@ Interface Slant6: Engine 
@ End / / Slant6 
@ Implementation Slant6 

- (NSString *) description {
NSLog (@ "I am a slant-6. VROOOM!"); 
} 

@ End / / Slant6 

/ / ---------------------------------------- 
@ Interface Car: NSObject {
Engine * engine; 
Tire * tires [4]; 
} 

- (Engine *) engine; 
- (Void) setEngine: (Engine *) newEngine; 

- (Tire *) tireAtIndex: (int) index; 
- (Void) setTire: (Tire *) tire atIndex: (int) index; 

- (Void) print; 

@ End / / Car 

@ Implementation Car 

- (Id) init {
if (self == [super init]) {
engine = [Engine new]; 
tires [0] = [Tire new]; 
tires [1] = [Tire new]; 
tires [2] = [Tire new]; 
tires [3] = [Tire new]; 
} 
return self; 
} 

- (Engine *) engine {
return engine; 
} 

- (Void) setEngine: (Engine *) newEngine {
engine = newEngine; 
} 

- (Tire *) tireAtIndex: (int) index {
if (index <0 | | index> 3) {
NSLog (@ "bad index (% d) in tireAtIndex", index); 
exit (1); 
} 
return tires [index]; 
} 

- (Void) setTire: (Tire *) tire atIndex: (int) index {
if (index <0 | | index> 3) {
NSLog (@ "bad index (% d) in setTire: atIndex", index); 
exit (1); 
} 

tires [index] = tire; 

} 

- (Void) print {

NSLog (@ "% @", engine); 
NSLog (@ "% @", tires [0]); 
NSLog (@ "% @", tires [1]); 
NSLog (@ "% @", tires [2]); 
NSLog (@ "% @", tires [3]); 
} 
@ End / / Car 

/ / ------------------------------------------------ - 
int main (int argc, const char * argv []) {
Car * car = [Car new]; 
/ / Engine * engine = [Engine new]; 
Slant6 * slant6 = [Slant6 new]; 
[Car setEngine: slant6]; 

int i; 
for (i = 0; i <4; i + +) {
/ / Tire * tire = [Tire new]; 
Tire * tire = [AllWeatherRadial new]; 
[Car setTire: tire atIndex: i]; 
} 

car.print; 
return 0; 
} 

Reply:
Breakpoints Bubble Look, look where the problem
Reply:

quote 1 floor yuhuangc reply:

breakpoint bubble look, look where the problem lies

Thank you reply that he put a piece of code was wrong, had the return, I NSLog print directly, no return, that is, the following code

 @ interface Slant6: Engine 
@ End / / Slant6 
@ Implementation Slant6 

- (NSString *) description {
NSLog (@ "I am a slant-6. VROOOM!"); 
} 

@ End / / Slant6 

Reply:

cited two floor z550946941 reply:

quote 1 floor yuhuangc reply: Breakpoint bubble look, look where the problem
Thank you reply that he put a piece of code was wrong, had the return, I NSLog print directly, no return, that is, the following code
Objective C code? 123456789 @ interface Slant6: Engine @ end / / Slant6 @ implementation Slant6 - (NS ......

Right, so many breakpoints, what can come out of this problem.