Instance Method

lock()

Attempts to acquire a lock on the context.

Declaration

func lock()

Discussion

This method blocks a thread’s execution until the lock can be acquired. An application protects a critical section of code by requiring a thread to acquire a lock before executing the code. Once the critical section is past, the thread relinquishes the lock by invoking unlock().

Sending this message to a managed object context helps the framework to understand the scope of a transaction in a multi-threaded environment. It is preferable to use the NSManagedObjectContext’s implementation of NSLocking instead using of a separate mutex object.

If you lock (or successfully tryLock) a managed object context, the thread in which the lock call is made must keep a strong reference to the context until it invokes unlock, otherwise if the context is deallocated this will result in deadlock.

See Also

Deprecated

func unlock()

Relinquishes a previously acquired lock.

Deprecated
func tryLock() -> Bool

Attempts to acquire a lock.

Deprecated

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