iOS中正确处理dealloc方法(2)

Special Considerations
When garbage collection is enabled, the garbage collector sends finalize to the receiver instead of dealloc, and this method is a no-op.

If you are using manual reference counting, subclasses must implement their own versions of dealloc to allow the release of any additional memory consumed by the object—such as dynamically allocated storage for data or object instance variables owned by the deallocated object. After performing the class-specific deallocation, the subclass method should incorporate superclass versions of dealloc through a message to super