Packages

class ZkAsyncSemaphore extends AnyRef

ZkAsyncSemaphore is a distributed semaphore with asynchronous execution. Grabbing a permit constitutes a vote on the number of permits the semaphore can permit and returns a Future[Permit]. If consensus on the number of permits is lost, an exception is raised when acquiring a permit (so expect it).

Care must be taken to handle zookeeper client session expiry. A ZkAsyncSemaphore cannot be used after the zookeeper session has expired. Likewise, any permits acquired via the session must be considered invalid. Additionally, it is the client's responsibility to determine if a permit is still valid in the case that the zookeeper client becomes disconnected.

Attempts to clone AsyncSemaphore

Ex.

implicit val timer = new JavaTimer(true)
val connector = NativeConnector("localhost:2181", 5.seconds, 10.minutes)
val zk = ZkClient(connector).withRetryPolicy(RetryPolicy.Basic(3))
val path = "/testing/twitter/service/charm/shards"
val sem = new ZkAsyncSemaphore(zk, path, 4)

sem.acquire flatMap { permit =>
  Future { ... } ensure { permit.release }
} // handle { ... }
Linear Supertypes
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. ZkAsyncSemaphore
  2. AnyRef
  3. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Instance Constructors

  1. new ZkAsyncSemaphore(zk: ZkClient, path: String, numPermits: Int, maxWaiters: Option[Int] = None)

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. def acquire(): Future[Permit]
  5. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  6. def clone(): AnyRef
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  7. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  8. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  9. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  10. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  12. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  13. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  14. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  15. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  16. var numPermitsAvailable: Int
  17. var numWaiters: Int
  18. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  19. def toString(): String
    Definition Classes
    AnyRef → Any
  20. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  21. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  22. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )

Inherited from AnyRef

Inherited from Any

Ungrouped