Mailing Lists: Apple Mailing Lists
Image of Mac OS face in stamp
 
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Thread safety with background fetching

Hi List,

Having read the Apple documentation and beginner guides on threading, I am still a little confused about protecting my variables from access by multiple threads.

A sample of my code is as follows:

@interface Class1 : NSObject
{
	XMLFetcherParser *fetcherParser;
}
- (void)doBackgroundFetch;
- (void)receiveItem:(Item *)newItem;
@end

@implementation Class1

- (void)doBackgroundFetch
{
	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
	
	fetcherParser = [[XMLFetcherParser alloc] init];
	[fetcherParser doYourThing];

	[fetcherParser release];
	[pool release];
}

- (void)receiveItem:(Item *)newItem
{
	// Add newItem to an array
}

@end

For usage, the summary is that I do:

[NSThread detachNewThreadSelector:@selector(doBackgroundFetch) toTarget:self withObject:nil];

and then -[XMLFetcherParser doYourThing] repeatedly sends newly created objects to receiveItem: using the performSelectorOnMainThread method. Once the spawned thread has done this, it never uses the sent object again.


My question is how should I protect this code from thread related problems? Do I just place @synchronized(){} blocks around the code in receiveItem: and it's counterpart in the spawned thread? Or is that just plain wrong? Or (likely) am I barking up totally the wrong tree?


Regards,

Ben

_______________________________________________

Cocoa-dev mailing list (email@hidden)

Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/email@hidden

This email sent to email@hidden


Visit the Apple Store online or at retail locations.
1-800-MY-APPLE

Contact Apple | Terms of Use | Privacy Policy

Copyright © 2007 Apple Inc. All rights reserved.