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org.apache.catalina.cluster.util
public class: SingleRemoveSynchronizedAddLock [javadoc | source]
java.lang.Object
   org.apache.catalina.cluster.util.SingleRemoveSynchronizedAddLock
The class SingleRemoveSynchronizedAddLock implement locking for accessing the queue by a single remove thread and multiple add threads. A thread is only allowed to be either the remove or an add thread. The lock can either be owned by the remove thread or by a single add thread. If the remove thread tries to get the lock, but the queue is empty, it will block (poll) until an add threads adds an entry to the queue and releases the lock. If the remove thread and add threads compete for the lock and an add thread releases the lock, then the remove thread will get the lock first. The remove thread removes all entries in the queue at once and proceeses them without further polling the queue. The lock is not reentrant, in the sense, that all threads must release an owned lock before competing for the lock again!
Constructor:
 public SingleRemoveSynchronizedAddLock() 
 public SingleRemoveSynchronizedAddLock(boolean dataAvailable) 
Method from org.apache.catalina.cluster.util.SingleRemoveSynchronizedAddLock Summary:
abortRemove,   getAddWaitTimeout,   getRemoveWaitTimeout,   isAddLocked,   isDataAvailable,   isRemoveLocked,   isRemovePolling,   lockAdd,   lockRemove,   setAddWaitTimeout,   setRemoveWaitTimeout,   unlockAdd,   unlockRemove
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.catalina.cluster.util.SingleRemoveSynchronizedAddLock Detail:
 public synchronized  void abortRemove() 
    Abort any polling remover thread
 public synchronized long getAddWaitTimeout() 
 public synchronized long getRemoveWaitTimeout() 
 public synchronized boolean isAddLocked() 
    Check if an add thread owns the lock.
 public synchronized boolean isDataAvailable() 
    Check if the locked object has data available i.e. the remover can stop poling and get the lock.
 public synchronized boolean isRemoveLocked() 
    Check if the remove thread owns the lock.
 public synchronized boolean isRemovePolling() 
    Check if the remove thread is polling.
 public synchronized  void lockAdd() 
    Acquires the lock by an add thread and sets the add flag. If any add thread or the remove thread already acquired the lock this add thread will block until the lock is released.
 public synchronized boolean lockRemove() 
    Acquires the lock by the remove thread and sets the remove flag. If any add thread already acquired the lock or the queue is empty, the remove thread will block until the lock is released and the queue is not empty.
 public synchronized  void setAddWaitTimeout(long timeout) 
    Set value of addWaitTimeout
 public synchronized  void setRemoveWaitTimeout(long timeout) 
    Set value of removeWaitTimeout
 public synchronized  void unlockAdd(boolean dataAvailable) 
    Releases the lock by an add thread and reset the remove flag. If the reader thread is polling, notify it.
 public synchronized  void unlockRemove() 
    Releases the lock by the remove thread and reset the add flag. Notify all waiting add threads, that the lock has been released by the remove thread.