JSBarrierOperationQueue

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JSBarrierOperationQueue

JSBarrierOperationQueue is an NSOperationQueue subclass that allows you to add operations that behave as a barrier. Basically providing the same functionality dispatch_barrier_async provides in the GCD world.

Quote from dispatch_barrier_async documentation:

Calls to this function always return immediately after the block has been submitted and never wait for the block to be invoked. When the barrier block reaches the front of a private concurrent queue, it is not executed immediately. Instead, the queue waits until its currently executing blocks finish executing. At that point, the barrier block executes by itself. Any blocks submitted after the barrier block are not executed until the barrier block completes.

Usage

• Clone the repository using

$ git clone https://github.com/JaviSoto/JSBarrierOperationQueue.git

• Add JSBarrierOperationQueue.{h,m} to your project.
• Create a JSBarrierOperationQueue just like you would create an NSOperationQueue.
• Submit operations using -addOperation:
• Submit barrier operations using:

- (void)addBarrierOperation:(NSOperation *)operation;

or

- (void)addBarrierOperationWithBlock:(void (^)(void))block;

• This behaves like dispatch_barrier_async() because it doesn't block the calling thread. If you want the same behaviour as dispatch_barrier_sync, you can just do:

JSBarrierOperationQueue *queue = ...
NSOperation *operation = ...

[queue addBarrierOperation:operation];
[operation waitUntilFinished];

Tests

• You can run the tests with:

$ make test

Compatibility

• Supports ARC.
• Compatible with iOS4.0+
• Compatible with Mac OSX 10.6+

License

Copyright 2012 Javier Soto ([email protected])

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Attribution is not required, but appreciated.