Package org.opendaylight.infrautils.utils.concurrent

Class NamedSimpleReentrantLock<T>

java.lang.Object

java.util.concurrent.locks.ReentrantLock

org.opendaylight.infrautils.utils.concurrent.NamedSimpleReentrantLock<T>

Type Parameters:

T - the name type, required to be effectively immutable where T.hashCode() and T.equals() is concerned

All Implemented Interfaces:

Serializable, Lock

public final class NamedSimpleReentrantLock<T>
extends ReentrantLock

A ReentrantLock which has a name and provides simplified locking operations.

Author:

Robert Varga

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	NamedSimpleReentrantLock.Acquired	Result of a successful lock operation, representing a single lease on the lock.
static class	NamedSimpleReentrantLock.AcquireResult	Base result of a locking operation.

Constructor Summary

Constructors

Constructor	Description
NamedSimpleReentrantLock(T name)

Method Summary

Modifier and Type	Method	Description
NamedSimpleReentrantLock.Acquired	acquire()	Acquires the lock.
T	getName()
String	toString()
NamedSimpleReentrantLock.AcquireResult	tryAcquire()	Acquires the lock for the given key only if it is not held by another thread at the time of invocation.
NamedSimpleReentrantLock.AcquireResult	tryAcquire(long timeout, TimeUnit unit)	Tries to acquire the lock for the given key if it is not held by another thread within the given waiting time.

Methods inherited from class java.util.concurrent.locks.ReentrantLock

getHoldCount, getOwner, getQueuedThreads, getQueueLength, getWaitingThreads, getWaitQueueLength, hasQueuedThread, hasQueuedThreads, hasWaiters, isFair, isHeldByCurrentThread, isLocked, lock, lockInterruptibly, newCondition, tryLock, tryLock, unlock

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

NamedSimpleReentrantLock

public NamedSimpleReentrantLock(T name)

Method Detail

getName

public T getName()

tryAcquire

public NamedSimpleReentrantLock.AcquireResult tryAcquire(long timeout,
                                                         TimeUnit unit)

Tries to acquire the lock for the given key if it is not held by another thread within the given waiting time. See ReentrantLock.tryLock(long, TimeUnit) for more details.

Example of use::

     NamedSimpleReentrantLockslt;?> lock;

     try (AcquireResult acq = lock.tryAcquire(1, TimeUnit.SECONDS)) {
         // maybe locked region, not safe

         if (acq.wasAcquired()) {
             // locked region
         } else {
             // unlocked region
         }
     });

     // lock released
 

Parameters:

timeout - the time to wait for the lock

unit - the time unit of the timeout argument

Returns:

lock operation result. If the lock was free and was acquired by the current thread, NamedSimpleReentrantLock.AcquireResult.wasAcquired() will return true. If it reports false, the locking attempt has failed, either due to lock time expiring or the thread being interrupted while waiting.

tryAcquire

public NamedSimpleReentrantLock.AcquireResult tryAcquire()

Acquires the lock for the given key only if it is not held by another thread at the time of invocation. See ReentrantLock.tryLock() for more details.

Example of use::

     NamedSimpleReentrantLock<?> lock;

     try (AcquireResult acq = locks.tryAcquire()) {
         // maybe locked region

         if (acq.wasAcquired()) {
             // locked region
         } else {
             // unlocked region
         }
     });

     // lock released
 

Returns:

lock operation result. If the lock was free and was acquired by the current thread, NamedSimpleReentrantLock.AcquireResult.wasAcquired() will return true. If it reports false, the locking attempt has failed,because another thread is currently holding the lock.

acquire

public NamedSimpleReentrantLock.Acquired acquire()

Acquires the lock. See ReentrantLock.lock() for more details. Example of use:

     NamedSimpleReentrantLocks<?> lock;

     try (Acquired acq = lock.acquire()) {
          // locked region
     }

     // lock released
 

toString

public String toString()

Overrides:

toString in class ReentrantLock