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iphoneobjective-ciosmemory-managementsbjson

SBJsonParser Memory Leak


I've used leaks to locate a memory leak that is related to SBJsonParser tho I don't understand why I'm getting it? I was hoping someone might be able to shed some insight. Leaks reports that the leak is coming from a method called objectWithURL. This method is called from a method called downloadJSONFeed. I have shown both below.

Any insight appreciated.

- (id) objectWithUrl:(NSURL *)url
{

    SBJsonParser *jsonParser = [SBJsonParser new];
    NSString *jsonString = [self stringWithUrl:url];

    // Parse the JSON into an Object
    return [jsonParser objectWithString:jsonString error:NULL];

}

- (void) downloadJSONFeed 
{

    //set up query
    NSString *lat  = [NSString stringWithFormat:@"%f", ad.locationManager.location.coordinate.latitude]; 
    NSString *lon = [NSString stringWithFormat:@"%f", ad.locationManager.location.coordinate.longitude];
    NSString *postValues = [NSString stringWithFormat:@"http://vivid-wind-8436.herokuapp.com/bathrooms/nearby.json/?lat=%@&lon=%@",lat, lon];


    //get server response
    id response = [self objectWithUrl:[NSURL URLWithString:postValues]];

    //store in dictionary
    NSDictionary *dictionary = (NSDictionary *)response;  

    //array for json data
     NSMutableArray *jsonData = [[NSMutableArray alloc] init];

    for (NSDictionary *dict in dictionary)
    {
        Bathroom *bathroom = [[[Bathroom alloc] init] autorelease];
        bathroom.name = [dict objectForKey:@"name"];
        bathroom.street = [dict objectForKey:@"street"];
        bathroom.city = [dict objectForKey:@"city"];
        bathroom.state = [dict objectForKey:@"state"];
        bathroom.postal = [dict objectForKey:@"postal"];        
        bathroom.country = [dict objectForKey:@"country"];
        bathroom.accessibility = [dict objectForKey:@"access"];
        bathroom.gendered = [dict objectForKey:@"bathroomtype"];
        bathroom.availability = [dict objectForKey:@"avail"];
        bathroom.directions = [dict objectForKey:@"directions"];
        bathroom.comment = [dict objectForKey:@"comment"];
        bathroom.distance = [dict objectForKey:@"distance"];
        bathroom.lat = [dict objectForKey:@"lat"];
        bathroom.lon = [dict objectForKey:@"lon"];

        [jsonData addObject:bathroom];
    } 

    //now sort array by distance
    NSSortDescriptor *sortDescriptor;
    sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:@"distance"                                                  ascending:YES] autorelease];
    NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
    NSArray *sortedArray;
    sortedArray = [jsonData sortedArrayUsingDescriptors:sortDescriptors];
    //dataArray = [[NSMutableArray alloc] init];

    //add objects to data array
    [dataArray addObjectsFromArray:sortedArray];


    //release json data
    [jsonData release];

}    

Solution

  • [SBJsonParser new] equals to [[SBJsonParser alloc] init]. By calling this objectWithUrl owned the created SBJsonParser object, so you need to release it within this method:

    SBJsonParser *jsonParser = [[SBJsonParser new] autorelease];
    

    You can also:

    - (id)objectWithUrl:(NSURL *)url
    {
        SBJsonParser *jsonParser = [SBJsonParser new];
        NSString *jsonString = [self stringWithUrl:url];
    
        // Parse the JSON into an Object
        id jsonObject = [jsonParser objectWithString:jsonString error:NULL];
        [jsonParser release];
    
        return jsonObject;
    }
    

    Refer to Another iPhone Memory leak issue.