decaf::util::concurrent::locks::ReentrantReadWriteLock Class Reference

#include <src/main/decaf/util/concurrent/locks/ReentrantReadWriteLock.h>

Inheritance diagram for decaf::util::concurrent::locks::ReentrantReadWriteLock:

[legend]

Public Member Functions
	ReentrantReadWriteLock ()
	Creates a new ReentrantReadWriteLock with the default ordering property of Not-Fair.
	ReentrantReadWriteLock (bool fair)
	Creates a new ReentrantReadWriteLock with the given fairness policy.
virtual	~ReentrantReadWriteLock ()
virtual decaf::util::concurrent::locks::Lock &	readLock ()
	Returns the lock used for reading. Returns: the lock used for reading.
virtual decaf::util::concurrent::locks::Lock &	writeLock ()
	Returns the lock used for writing. Returns: the lock used for writing.
bool	isFair () const
	Returns true if this lock has fairness set true.
int	getReadLockCount () const
	Queries the number of read locks held for this lock.
bool	isWriteLocked () const
	Queries if the write lock is held by any thread.
bool	isWriteLockedByCurrentThread () const
	Queries if the write lock is held by the current thread.
int	getWriteHoldCount () const
	Queries the number of reentrant write holds on this lock by the current thread.
int	getReadHoldCount () const
	Queries the number of reentrant read holds on this lock by the current thread.
bool	hasWaiters (Condition *condition) const
	Queries whether any threads are waiting on the given condition associated with the write lock.
int	getWaitQueueLength (Condition *condition) const
	Gets an estimated count of the number of threads that are currently waiting on the given Condition object, this value changes dynamically so the result of this method can be invalid immediately after it is called.
std::string	toString () const
	Returns a string identifying this lock, as well as its lock state.
bool	hasQueuedThreads () const
	Queries whether any threads are waiting to acquire the read or write lock.
bool	hasQueuedThread (decaf::lang::Thread *thread) const
	Queries whether the given thread is waiting to acquire either the read or write lock.
int	getQueueLength () const
	Returns an estimate of the number of threads waiting to acquire either the read or write lock.
Protected Member Functions
decaf::util::Collection < decaf::lang::Thread * > *	getWaitingThreads (Condition *condition) const
	Creates and returns a new Collection object that contains all the threads that may be waiting on the given Condition object instance at the time this method is called.
decaf::util::Collection < decaf::lang::Thread * > *	getQueuedThreads () const
	Returns a collection containing threads that may be waiting to acquire either the read or write lock.
decaf::util::Collection < decaf::lang::Thread * > *	getQueuedWriterThreads () const
	Returns a collection containing threads that may be waiting to acquire the write lock.
decaf::util::Collection < decaf::lang::Thread * > *	getQueuedReaderThreads () const
	Returns a collection containing threads that may be waiting to acquire the read lock.
decaf::lang::Thread *	getOwner () const
	Returns the thread that currently owns the write lock, or NULL if not owned.

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Detailed Description

Since:

1.0

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Constructor & Destructor Documentation

decaf::util::concurrent::locks::ReentrantReadWriteLock::ReentrantReadWriteLock

(

)

Creates a new ReentrantReadWriteLock with the default ordering property of Not-Fair.

decaf::util::concurrent::locks::ReentrantReadWriteLock::ReentrantReadWriteLock

(

bool

fair

)

Creates a new ReentrantReadWriteLock with the given fairness policy.

Parameters:

fair

Boolean value indicating whether this lock uses a fair or non-fair policy.

virtual decaf::util::concurrent::locks::ReentrantReadWriteLock::~ReentrantReadWriteLock

(

)

[virtual]

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Member Function Documentation

decaf::lang::Thread* decaf::util::concurrent::locks::ReentrantReadWriteLock::getOwner

(

)

const [protected]

Returns the thread that currently owns the write lock, or NULL if not owned.

When this method is called by a thread that is not the owner, the return value reflects a best-effort approximation of current lock status. For example, the owner may be momentarily NULL even if there are threads trying to acquire the lock but have not yet done so. This method is designed to facilitate construction of subclasses that provide more extensive lock monitoring facilities.

Returns:

the owner thread pointer, or NULL if not currently owned.

decaf::util::Collection<decaf::lang::Thread*>* decaf::util::concurrent::locks::ReentrantReadWriteLock::getQueuedReaderThreads

(

)

const [protected]

Returns a collection containing threads that may be waiting to acquire the read lock.

Because the actual set of threads may change dynamically while constructing this result, the returned collection is only a best-effort estimate. The elements of the returned collection are in no particular order. This method is designed to facilitate construction of subclasses that provide more extensive lock monitoring facilities.

Returns:

the collection of threads

decaf::util::Collection<decaf::lang::Thread*>* decaf::util::concurrent::locks::ReentrantReadWriteLock::getQueuedThreads

(

)

const [protected]

Returns a collection containing threads that may be waiting to acquire either the read or write lock.

Because the actual set of threads may change dynamically while constructing this result, the returned collection is only a best-effort estimate. The elements of the returned collection are in no particular order. This method is designed to facilitate construction of subclasses that provide more extensive monitoring facilities.

Returns:

the collection of threads

decaf::util::Collection<decaf::lang::Thread*>* decaf::util::concurrent::locks::ReentrantReadWriteLock::getQueuedWriterThreads

(

)

const [protected]

Returns a collection containing threads that may be waiting to acquire the write lock.

Because the actual set of threads may change dynamically while constructing this result, the returned collection is only a best-effort estimate. The elements of the returned collection are in no particular order. This method is designed to facilitate construction of subclasses that provide more extensive lock monitoring facilities.

Returns:

the collection of threads

int decaf::util::concurrent::locks::ReentrantReadWriteLock::getQueueLength

(

)

const

Returns an estimate of the number of threads waiting to acquire either the read or write lock.

The value is only an estimate because the number of threads may change dynamically while this method traverses internal data structures. This method is designed for use in monitoring of the system state, not for synchronization control.

Returns:

the estimated number of threads waiting for this lock

int decaf::util::concurrent::locks::ReentrantReadWriteLock::getReadHoldCount

(

)

const

Queries the number of reentrant read holds on this lock by the current thread.

A reader thread has a hold on a lock for each lock action that is not matched by an unlock action.

Returns:

the number of holds on the read lock by the current thread, or zero if the read lock is not held by the current thread

int decaf::util::concurrent::locks::ReentrantReadWriteLock::getReadLockCount

(

)

const

Queries the number of read locks held for this lock.

This method is designed for use in monitoring system state, not for synchronization control.

Returns:

the number of read locks held.

decaf::util::Collection<decaf::lang::Thread*>* decaf::util::concurrent::locks::ReentrantReadWriteLock::getWaitingThreads

(

Condition *

condition

)

const [protected]

Creates and returns a new Collection object that contains all the threads that may be waiting on the given Condition object instance at the time this method is called.

Returns:

a Collection pointer that contains waiting threads on given Condition object. The caller owns the returned pointer.

Exceptions:

	NullPointerException	if the ConditionObject pointer is NULL.
	IllegalArgumentException	if the ConditionObject is not associated with this Synchronizer.
	IllegalMonitorStateException	if the caller does not hold exclusive synchronization.

int decaf::util::concurrent::locks::ReentrantReadWriteLock::getWaitQueueLength

(

Condition *

condition

)

const

Gets an estimated count of the number of threads that are currently waiting on the given Condition object, this value changes dynamically so the result of this method can be invalid immediately after it is called.

The Condition object must be associated with this Lock or an exception will be thrown.

Returns:

an estimate of the number of waiting threads.

Exceptions:

	NullPointerException	if the ConditionObject pointer is NULL.
	IllegalArgumentException	if the ConditionObject is not associated with this Synchronizer.
	IllegalMonitorStateException	if the caller does not hold exclusive synchronization.

int decaf::util::concurrent::locks::ReentrantReadWriteLock::getWriteHoldCount

(

)

const

Queries the number of reentrant write holds on this lock by the current thread.

A writer thread has a hold on a lock for each lock action that is not matched by an unlock action.

Returns:

the number of holds on the write lock by the current thread, or zero if the write lock is not held by the current thread

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::hasQueuedThread

(

decaf::lang::Thread *

thread

)

const

Queries whether the given thread is waiting to acquire either the read or write lock.

Note that because cancellations may occur at any time, a true return does not guarantee that this thread will ever acquire a lock. This method is designed primarily for use in monitoring of the system state.

Parameters:

thread

The thread that will be queried for.

Returns:

true if the given thread is queued waiting for this lock

Exceptions:

NullPointerException

if the thread is NULL.

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::hasQueuedThreads

(

)

const

Queries whether any threads are waiting to acquire the read or write lock.

Note that because cancellations may occur at any time, a true return does not guarantee that any other thread will ever acquire a lock. This method is designed primarily for use in monitoring of the system state.

Returns:

if there may be other threads waiting to acquire the lock

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::hasWaiters

(

Condition *

condition

)

const

Queries whether any threads are waiting on the given condition associated with the write lock.

Note that because timeouts and interrupts may occur at any time, a true return does not guarantee that a future signal will awaken any threads. This method is designed primarily for use in monitoring of the system state.

Parameters:

condition

The condition to be queried for waiters.

Returns:

true if there are any waiting threads

Exceptions:

	NullPointerException	if the ConditionObject pointer is NULL.
	IllegalArgumentException	if the ConditionObject is not associated with this Lock.
	IllegalMonitorStateException	if the caller does not hold exclusive synchronization.

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::isFair

(

)

const

Returns true if this lock has fairness set true.

Returns:

true if the Lock uses a fair policy otherwise false.

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::isWriteLocked

(

)

const

Queries if the write lock is held by any thread.

This method is designed for use in monitoring system state, not for synchronization control.

Returns:

true if any thread holds the write lock and false otherwise

bool decaf::util::concurrent::locks::ReentrantReadWriteLock::isWriteLockedByCurrentThread

(

)

const

Queries if the write lock is held by the current thread.

Returns:

true if the current thread holds the write lock and false otherwise

virtual decaf::util::concurrent::locks::Lock& decaf::util::concurrent::locks::ReentrantReadWriteLock::readLock

(

)

[virtual]

Returns the lock used for reading.

Returns:

the lock used for reading.

Implements decaf::util::concurrent::locks::ReadWriteLock.

Referenced by decaf::util::concurrent::CopyOnWriteArrayList< E >::contains(), decaf::util::concurrent::CopyOnWriteArrayList< E >::get(), decaf::util::concurrent::CopyOnWriteArrayList< E >::indexOf(), decaf::util::concurrent::CopyOnWriteArrayList< E >::isEmpty(), decaf::util::concurrent::CopyOnWriteArrayList< E >::iterator(), decaf::util::concurrent::CopyOnWriteArrayList< E >::lastIndexOf(), decaf::util::concurrent::CopyOnWriteArrayList< E >::listIterator(), decaf::util::concurrent::CopyOnWriteArrayList< E >::size(), decaf::util::concurrent::CopyOnWriteArrayList< E >::toArray(), and decaf::util::concurrent::CopyOnWriteArrayList< E >::toString().

std::string decaf::util::concurrent::locks::ReentrantReadWriteLock::toString

(

)

const

Returns a string identifying this lock, as well as its lock state.

The state, in brackets, includes the String "Write locks =" followed by the number of reentrantly held write locks, and the String "Read locks =" followed by the number of held read locks.

Returns:

a string identifying this lock, as well as its lock state

virtual decaf::util::concurrent::locks::Lock& decaf::util::concurrent::locks::ReentrantReadWriteLock::writeLock

(

)

[virtual]

Returns the lock used for writing.

Returns:

the lock used for writing.

Implements decaf::util::concurrent::locks::ReadWriteLock.

Referenced by decaf::util::concurrent::CopyOnWriteArrayList< E >::add(), decaf::util::concurrent::CopyOnWriteArrayList< E >::addAll(), decaf::util::concurrent::CopyOnWriteArrayList< E >::addAllAbsent(), decaf::util::concurrent::CopyOnWriteArrayList< E >::addIfAbsent(), decaf::util::concurrent::CopyOnWriteArrayList< E >::clear(), decaf::util::concurrent::CopyOnWriteArrayList< E >::copy(), decaf::util::concurrent::CopyOnWriteArrayList< E >::CopyOnWriteArrayList(), decaf::util::concurrent::CopyOnWriteArrayList< E >::lock(), decaf::util::concurrent::CopyOnWriteArrayList< E >::operator=(), decaf::util::concurrent::CopyOnWriteArrayList< E >::remove(), decaf::util::concurrent::CopyOnWriteArrayList< E >::removeAll(), decaf::util::concurrent::CopyOnWriteArrayList< E >::removeAt(), decaf::util::concurrent::CopyOnWriteArrayList< E >::retainAll(), decaf::util::concurrent::CopyOnWriteArrayList< E >::set(), decaf::util::concurrent::CopyOnWriteArrayList< E >::tryLock(), and decaf::util::concurrent::CopyOnWriteArrayList< E >::unlock().

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The documentation for this class was generated from the following file:

• src/main/decaf/util/concurrent/locks/ReentrantReadWriteLock.h