NaiveReadWriteLock

Naive read-write lock, meant for low-contention scenarios.

the read lock can be acquired by multiple threads at the same time
the write lock can be acquired by only a single thread and blocks all other reads and writes that are competing for the same lock
writes have priority, so a pending write will come before subsequent read attempts
it has re-entrant behavior. Upgrading from a read to a write lock involves releasing the read-lock first, however downgrading from a write to a read lock is done directly
synchronization is based on spinlocks so threads never go into a wait-state (monitor-enter)

Not a good idea to use it in high-contention scenarios, as the locking is unfair (i.e. writes have priority over reads, but otherwise it provides no guarantees to the fairness of what thread gets the lock next), plus spinlocking means that threads never wait and thus consume CPU resources.

Example:

class Fibonacci {
private[this] val lock = new NaiveReadWriteLock()
private[this] var a, b = 1

def get = lock.readLock(b)

def next() = lock.writeLock {
  val tmp = b
  b = a + b
  a = tmp
  get
}
}

Linear Supertypes

ReadWriteLock, Lock, AnyRef, Any

Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def acquire[T](cb: ⇒ T): T

Acquires a lock meant for both reading and writing.
Acquires a lock meant for both reading and writing.

Definition Classes
ReadWriteLock → Lock
final def asInstanceOf[T0]: T0

Definition Classes
Any
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
def readLock[T](cb: ⇒ T): T

Acquires a lock meant for reading.
Acquires a lock meant for reading. Multiple threads can acquire the lock at the same time. It is also re-entrant (i.e. the same thread can acquire it multiple times)

Definition Classes
NaiveReadWriteLock → ReadWriteLock
Annotations
@throws( classOf[InterruptedException] )
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
def writeLock[T](cb: ⇒ T): T

Acquires a lock meant for writing.
Acquires a lock meant for writing. Only one thread can acquire the write lock at the same time and it has to wait until all active reads are finished.

Definition Classes
NaiveReadWriteLock → ReadWriteLock
Annotations
@throws( classOf[InterruptedException] )

final class NaiveReadWriteLock extends ReadWriteLock

Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

final def acquire[T](cb: ⇒ T): T

final def asInstanceOf[T0]: T0

def clone(): AnyRef

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

def readLock[T](cb: ⇒ T): T

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

def writeLock[T](cb: ⇒ T): T

Inherited from ReadWriteLock

Inherited from Lock

Inherited from AnyRef

Inherited from Any

Ungrouped