How to release the NSUrlConnection class object,NSMutableData class object?

iam making one applciation.In that iam using the NSUrlconnection class.Below one is my code.

- (void)viewDidLoad {
[super viewDidLoad];
responsedata = [[NSMutableData data] retain];
NSString *url = [NSString stringWithFormat:@"https://www.google.com"];
NSURL *URL = [NSURL URLWithString:url];
NSURLRequest *request=[[NSURLRequest alloc]initWithURL:URL];
[[NSURLConnection alloc] initWithRequest:request delegate:self];

[request release];
}

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response 
{

   [responsedata setLength:0];
}
 - (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[responsedata appendData:data];
   }

  - (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    }
  - (void)connectionDidFinishLoading:(NSURLConnection *)connection {

     [connection release];
    }

In this code when iam executing,it shows the memory leak at responsedata = [[NSMutableData data] retain];开发者_StackOverflow中文版 [[NSURLConnection alloc] initWithRequest:request delegate:self]; in viewDidLoad() .SO please tell me where it released.

1. You should save reference to your NSURLConnection :

   NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];

2. You should start it:

   [connection start];

3. And you should release it in didFailWithError or connectionDidFinishLoading.