com.h3c.dist.lock

Interface Lock

public interface Lock

Enables applications to perform specific operations on a lock. For type of locks refer to Lock types LockType

Method Summary

Methods

Modifier and Type	Method and Description
LockName	getName() Get LockName LockName associated with the Lock.
LockState	getState() Get current state LockState of the Lock.
void	lock() Acquire the lock.
boolean	tryLock() Acquires the lock only if it is available at the time of invocation.
boolean	tryLock(long timeOut, TimeUnit unit) Acquire lock with a timeout.
void	unlock() Release the lock which is previously acquired.

Method Detail

lock

void lock()
          throws InterruptedException,
                 ServiceNotAvailableException,
                 IOException

Acquire the lock. If lock is readily available, lock is granted otherwise caller is blocked until the lock is available.

Throws:

InterruptedException - Thread interrupted exception

ServiceNotAvailableException - Lock service is down currently

IOException - IO exception while data serialization

tryLock

boolean tryLock(long timeOut,
              TimeUnit unit)
                throws InterruptedException,
                       ServiceNotAvailableException,
                       IOException

Acquire lock with a timeout. If lock is readily available, lock is granted otherwise caller is blocked until the lock is available or the timer expires, which ever is earlier.

Parameters:

timeOut - Timeout value

unit - Timeout unit

Returns:

boolean true if lock acquired, false if timeout

Throws:

InterruptedException - Thread interrupted exception

ServiceNotAvailableException - Lock service down exception

IOException - IO exception while data serialization

tryLock

boolean tryLock()
                throws ServiceNotAvailableException,
                       InterruptedException,
                       IOException

Acquires the lock only if it is available at the time of invocation.

Returns:

true if lock acquired, false otherwise

Throws:

ServiceNotAvailableException - Lock service is down

InterruptedException - Operation interrupted exception

IOException - IO Exception while data serialization

unlock

void unlock()
            throws LockServiceException.LockNotAquiredException,
                   ServiceNotAvailableException,
                   InterruptedException

Release the lock which is previously acquired. If a lock which is blocked state is released, the previously blocked caller is woken up with lock released exception.

Throws:

LockServiceException.LockNotAquiredException - Lock is not in aquired state

ServiceNotAvailableException - Lock service is down

InterruptedException - Operation interrupted exception

getName

LockName getName()

Get LockName LockName associated with the Lock.

Returns:

LockName Lock information object corresponding to the lock.

getState

LockState getState()

Get current state LockState of the Lock.

Returns:

LockState