Question

Iam getting memory leaks in below code.

Is this is the proper way to handle memory?

Please do correct me.

-(void)getholidays
{   
   if (idarray!=nil) {
   [idarray release];
    idarray=nil;
     }
 idarray=[[NSMutableArray alloc]init];

   if (Countryarray!=nil) {
    [Countryarray release];
    Countryarray=nil;
     }
   Countryarray =[[NSMutableArray alloc] init];
   if (Holidaynamearray!=nil) {
    [Holidaynamearray release];
    Holidaynamearray=nil;
     }
   Holidaynamearray =[[NSMutableArray alloc] init];
   if (Datearray!=nil) {
    [Datearray release];
    Datearray=nil;
   }Datearray =[[NSMutableArray alloc] init];
    if (Dayarray!=nil) {
    [Dayarray release];
    Dayarray=nil;
   }Dayarray =[[NSMutableArray alloc] init];
   if (Favoritearray!=nil) {
    [Favoritearray release];
    Favoritearray=nil;
   }

   Favoritearray =[[NSMutableArray alloc] init];

   NSString *destinationPath = [self getdestinationPath];

   const char *dbpath = [destinationPath UTF8String];
    sqlite3_stmt    *statement;

    if (sqlite3_open(dbpath, &database) == SQLITE_OK)

    {
    NSString *querySQL;


    NSDate *today = [NSDate date];
    NSDateFormatter* formatter = [[[NSDateFormatter alloc] init] autorelease];
    [formatter setDateFormat:@"MMMM-dd-yyyy"];
    NSString *Todaystrng = [formatter stringFromDate:today];

    NSLog(@"today date %@",Todaystrng);

    querySQL=[NSString stringWithFormat:@"SELECT * FROM Holiday_Table WHERE CountryName in (SELECT Country_Name from Country WHERE Country_Selected =1) ORDER BY  Date ASC "];



    const char *query_stmt = [querySQL UTF8String];

    if (sqlite3_prepare_v2(database, query_stmt, -1, &statement, NULL) == SQLITE_OK)  
    {
        NSLog(@"success");
        while (sqlite3_step(statement) == SQLITE_ROW)
        {

            NSString *idstringfromdb=[[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 0)]; 
            NSString *countrynamestringfromdb=[[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 1)];
            NSString *holidaynamestringfromdb=[[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 2)];
            NSString *datestringfromdb=[[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 3)];

            //Below line gets leaking   
              NSString *daystringfromdb=[[NSString alloc] initWithUTF8String:(const char *)  sqlite3_column_text(statement, 4)];
                  //Belowline gets leaking
          NSString *favoritestringfromdb=[[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 5)];


            [idarray addObject:idstringfromdb];
            [idstringfromdb release];
            idstringfromdb=nil;
            [Countryarray addObject:countrynamestringfromdb];
            [countrynamestringfromdb release];
            countrynamestringfromdb=nil;
            [Holidaynamearray addObject:holidaynamestringfromdb];
            [holidaynamestringfromdb release];
            holidaynamestringfromdb=nil;
            [Datearray addObject:datestringfromdb];
            [datestringfromdb release];
            datestringfromdb=nil;

            [Dayarray addObject:daystringfromdb];
            [daystringfromdb release];
            daystringfromdb=nil;

            [Favoritearray addObject:favoritestringfromdb];
            [favoritestringfromdb release];
            favoritestringfromdb=nil;
        }
    }
    sqlite3_finalize(statement);
}
sqlite3_close(database);
}

Answer 1

As far as I can tell from your code the leak happens because of addObject to the array (which increases the retain count by one) make sure that when you remove the object and are done with it from the array you release it there as well.