لطفا منتظر باشید ...
This class implements the
ReadWriteLock interface. The locks returned by the
readLock( ) and writeLock( )
methods are instances of the inner classes
ReadLock and WriteLock.
ReentrantReadWriteLock defines a
"fair mode" and includes
instrumentation methods like ReentrantLock does.Any number of threads can acquire the read lock as long as no thread
holds or is attempting to acquire the write lock. When a thread
attempts to acquire the write lock, no new read locks are granted.
When all existing readers have relinquished the lock, the writer
acquires the lock, and no reads are allowed until the writer has
relinquished it. A thread that holds the write lock may downgrade to
a read lock by acquiring the read lock and then relinquishing the
write lock.Because the read lock is not exclusive, it cannot have a
Condition associated with it. The
ReadLock.newCondition( ) method throws
UnsupportedOperationException.
Figure 16-106. java.util.concurrent.locks.ReentrantReadWriteLock
public class ReentrantReadWriteLock implements ReadWriteLock, Serializable {
// Public Constructors
public ReentrantReadWriteLock ( );
public ReentrantReadWriteLock (boolean fair );
// Nested Types
public static class ReadLock implements Lock, Serializable;
public static class WriteLock implements Lock, Serializable;
// Public Instance Methods
public final int getQueueLength ( ); default:0
public int getReadLockCount ( ); default:0
public int getWaitQueueLength (Condition condition );
public int getWriteHoldCount ( ); default:0
public final boolean hasQueuedThread (Thread thread );
public final boolean hasQueuedThreads ( );
public boolean hasWaiters (Condition condition );
public final boolean isFair ( ); default:false
public boolean isWriteLocked ( ); default:false
public boolean isWriteLockedByCurrentThread ( ); default:false
public ReentrantReadWriteLock.ReadLock readLock ( );
public ReentrantReadWriteLock.WriteLock writeLock ( );
// Public Methods Overriding Object
public String toString ( );
// Protected Instance Methods
protected Thread getOwner ( );
protected java.util.Collection<Thread> getQueuedReaderThreads ( );
protected java.util.Collection<Thread> getQueuedThreads ( );
protected java.util.Collection<Thread> getQueuedWriterThreads ( );
protected java.util.Collection<Thread> getWaitingThreads (Condition condition );
} Passed To
ReentrantReadWriteLock.ReadLock.ReadLock( ),ReentrantReadWriteLock.WriteLock.WriteLock( )
