SBJson解析器内存泄漏

Question

我使用泄漏来定位与SBJsonParser相关的内存泄漏，我不明白为什么我会得到它？我希望有人能够提供一些见解。Leaks 报告泄漏来自一个名为 objectWithURL 的方法。此方法是从名为 downloadJSONFeed 的方法调用的。我在下面展示了两者。

任何见解都值得赞赏。

- (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];
}    

Answer 1

[SBJsonParser new]等于

[[SBJsonParser alloc] init] 。通过调用这个objectWithUrl拥有创建的SBJsonParser对象，所以你需要在此方法中释放它：

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

您还可以：

- (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;
}

请参阅另一个iPhone内存泄漏问题。

Answer 2

抱歉，

自从我用 Objective-C 编码以来已经有一段时间了，但这有用吗？

SBJsonParser *jsonParser = [[[SBJsonParser alloc] init] autorelease];

Answer 3

是的。 需要释放解析器。 将解析存储在堆栈变量中，释放解析器，然后返回。