```
public interface ClusteredLock
```
ClusteredLock is a data structure used for concurrent programming between Infinispan instances in cluster mode. A typical usage idiom for lock() will be : ClusteredLock lock = clm.get("lock"); lock.lock() .thenRun(() -> try { // manipulate protected state } finally { return lock.unlock(); } ) A typical usage idiom for tryLock() will be : lock.tryLock() .thenCompose(result -> { if (result) { try { // manipulate protected state } finally { return lock.unlock(); } } else { // Do something else } });

Since:

9.2

Author:

Katia Aresti, karesti@redhat.com

See Also:

Infinispan documentation

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`CompletableFuture<Boolean>`	`isLocked()`	Returns a `CompletableFuture` holding `true` when the lock is locked and `false` when the lock is released.
`CompletableFuture<Boolean>`	`isLockedByMe()`	Returns a `CompletableFuture` holding `true` when the lock is owned by the caller and `false` when the lock is owned by someone else or it's released.
`CompletableFuture<Void>`	`lock()`	Acquires the lock.
`CompletableFuture<Boolean>`	`tryLock()`	Acquires the lock only if it is free at the time of invocation.
`CompletableFuture<Boolean>`	`tryLock(long time, TimeUnit unit)`	If the lock is available this method returns immediately with the `CompletableFuture` holding the value `true`.
`CompletableFuture<Void>`	`unlock()`	Releases the lock.

- Method Detail
  - lock
```
CompletableFuture<Void> lock()
```
    Acquires the lock. If the lock is not available then the CompletableFuture waits until the lock has been acquired. Currently, there is no maximum time specified for a lock request to fail, so this could cause thread starvation.
    
    Returns:
    
    a completed CompletableFuture when the lock is acquired
    
    Throws:
    
    ClusteredLockException - when the lock does not exist
  - tryLock
```
CompletableFuture<Boolean> tryLock()
```
    Acquires the lock only if it is free at the time of invocation. Acquires the lock if it is available and returns immediately with with the CompletableFuture holding the value true. If the lock is not available then this method will return immediately with the CompletableFuture holding the value false.
    
    Returns:
    
    CompletableFuture(true) if the lock was acquired and CompletableFuture(false) otherwise
    
    Throws:
    
    ClusteredLockException - when the lock does not exist
  - tryLock
```
CompletableFuture<Boolean> tryLock(long time,
                                   TimeUnit unit)
```
    If the lock is available this method returns immediately with the CompletableFuture holding the value true. If the lock is not available then the CompletableFuture waits until :
    
    The lock is acquired
    
    The specified waiting time elapses
    
    If the lock is acquired then the CompletableFuture will complete with the value true. If the specified waiting time elapses then the CompletableFuture will complete with the value false. If the time is less than or equal to zero, the method will not wait at all.
    Parameters:
    
    time - , the maximum time to wait for the lock
    
    unit - , the time unit of the time argument
    
    Returns:
    
    CompletableFuture(true) if the lock was acquired and CompletableFuture(false) if the waiting time elapsed before the lock was acquired
    
    Throws:
    
    ClusteredLockException - when the lock does not exist
  - unlock
```
CompletableFuture<Void> unlock()
```
    Releases the lock. Only the holder of the lock may release the lock.
    
    Returns:
    
    a completed CompletableFuture when the lock is released
    
    Throws:
    
    ClusteredLockException - when the lock does not exist
  - isLocked
```
CompletableFuture<Boolean> isLocked()
```
    Returns a CompletableFuture holding true when the lock is locked and false when the lock is released.
    
    Returns:
    
    a CompletableFuture holding a Boolean
    
    Throws:
    
    ClusteredLockException - when the lock does not exist
  - isLockedByMe
```
CompletableFuture<Boolean> isLockedByMe()
```
    Returns a CompletableFuture holding true when the lock is owned by the caller and false when the lock is owned by someone else or it's released.
    
    Returns:
    
    a CompletableFuture holding a Boolean
    
    Throws:
    
    ClusteredLockException - when the lock does not exist

Interface ClusteredLock

Method Summary

Method Detail

lock

tryLock

tryLock

unlock

isLocked

isLockedByMe