Memory Leak Using NSXMLParser in NSConcreteMapTable - xcode

Question

I'm using NSXMLParser and I get a memory leak that points to NSConcreteMapTable, whatever that is:
The leak occurs at this line of code when calling the parser from my AppDelegate.m:
I have searched for a solution and can't see what I'm doing wrong.
Here is my code.
Any help is greatly appreciated.
lq
// * * * XMLParser.h * * *
#import <Foundation/Foundation.h>
#protocol NSXMLParserDelegate;
#interface XMLParser : NSObject
<NSXMLParserDelegate>
{
NSMutableArray *xmlArray;
BOOL storingCharacters;
float xmlDataVersion;
}
#property (nonatomic, retain) NSMutableArray *xmlArray;
#property (nonatomic) BOOL storingCharacters;
#property (nonatomic, assign) float xmlDataVersion;
-(BOOL)parseXMLFileAtURL:(NSURL *)URL parseError:(NSError **)error;
#end
// * * * XMLParser.m * * *
#import "XMLParser.h"
#implementation XMLParser
#synthesize xmlArray;
#synthesize storingCharacters;
#synthesize xmlDataVersion;
- (BOOL)parseXMLFileAtURL:(NSURL *)URL parseError:(NSError **)error {
BOOL result = YES;
if (xmlArray == nil) {
// this array holds row data extracted from the XML parser didStartElement method
xmlArray = [[NSMutableArray alloc] init];
}
[[NSURLCache sharedURLCache] setMemoryCapacity:0];
[[NSURLCache sharedURLCache] setDiskCapacity:0];
NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:URL];
if (parser != nil) {
[parser setDelegate:self];
[parser setShouldProcessNamespaces:NO];
[parser setShouldReportNamespacePrefixes:NO];
[[parser setShouldResolveExternalEntities:NO];
}
[parser parse];
if (parseError && error) {
*error = parseError;
result = NO;
}
[parser release];
return result;
}
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict {
if (qName) {
elementName = qName;
}
// Check the data version of the XML Data against my stored value
if ([elementName isEqualToString:#"data"]) {
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
self.xmlDataVersion = [[attributeDict objectForKey:#"version"] floatValue];
float storedDataVersion = [userDefaults floatForKey:kDataVersion];
if (self.xmlDataVersion <= storedDataVersion) {
// - - - - -> Abort parsing if the same or earlier data versions
[parser abortParsing];
}
}
if ([elementName isEqualToString:#"FirstColumnName"]) {
storingCharacters = YES;
} else if ([elementName isEqualToString:#"SecondColumnName"]) {
storingCharacters = YES;
// ... total of 16 elements
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
if (storingCharacters) {
[self.xmlArray addObject:string];
}
}
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
if (qName) {
elementName = qName;
}
// - - - - -> If at the end of a data row, save changes to object model
if ([elementName isEqualToString:#"ROW"]) {
// - - - - -> Make sure the data has the required number of elements before taking any action
if ([self.xmlArray count] == 16) {
// … //Store or Update Data in SQLite store depending on data values
}
[self.xmlArray removeAllObjects];
}
storingCharacters = NO;
}
-(void)dealloc {
[xmlArray release];
[super dealloc];
}
// * * * AppDelegate.m * * *
#import "XMLParser.h"
#implementation AppDelegate
- (void)applicationDidFinishLaunching:(UIApplication *)application {
NSURL *xmlURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:#"FileName" ofType:#"xml"]];
NSError *parseError = nil;
XMLParser *xmlParse = [[XMLParser alloc] init];
[xmlParse parseXMLFileAtURL:xmlURL parseError:&parseError];
[xmlParse release];
. . .
}

Answer 1

I found a solution in another SO post:
Use:
NSData * dataXml = [[NSData alloc] initWithContentsOfURL:URL];
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:dataXml];
[dataXml release];
Instead of:
NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:URL];
The leak goes away.

Answer 2

This is probably a leak in Apple code, since Foundation is reported as "Responsible Library". There's probably nothing you can do, but to report the bug to apple.