Package org.eclipse.aether.named.support

Class FileLockNamedLock

java.lang.Object

org.eclipse.aether.named.support.NamedLockSupport

org.eclipse.aether.named.support.FileLockNamedLock

All Implemented Interfaces:

AutoCloseable, NamedLock

public final class FileLockNamedLock
extends NamedLockSupport

Named lock that uses FileLock. An instance of this class is about ONE LOCK (one file) and is possibly used by multiple threads. Each thread (if properly coded re boxing) will try to obtain either shared or exclusive lock. As file locks are JVM-scoped (so one JVM can obtain same file lock only once), the threads share file lock and synchronize according to it. Still, as file lock obtain operation does not block (or in other words, the method that does block cannot be controlled for how long it blocks), we are "simulating" thread blocking using Retry utility. This implementation performs coordination not only on thread (JVM-local) level, but also on process level, as long as other parties are using this same "advisory" locking mechanism.

Since:

1.7.3

Field Summary

Fields inherited from class org.eclipse.aether.named.support.NamedLockSupport

logger

Constructor Summary

Constructors

Constructor	Description
FileLockNamedLock(String name, FileChannel fileChannel, NamedLockFactorySupport factory)

Method Summary

Modifier and Type	Method	Description
boolean	lockExclusively(long time, TimeUnit unit)	Tries to lock exclusively, may block for given time.
boolean	lockShared(long time, TimeUnit unit)	Tries to lock shared, may block for given time.
void	unlock()	Unlocks the lock, must be invoked by caller after one of the NamedLock.lockShared(long, TimeUnit) or NamedLock.lockExclusively(long, TimeUnit).

Methods inherited from class org.eclipse.aether.named.support.NamedLockSupport

close, name

Methods inherited from class java.lang.Object

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

Constructor Details

FileLockNamedLock

public FileLockNamedLock(String name,
 FileChannel fileChannel,
 NamedLockFactorySupport factory)

Method Details

lockShared

public boolean lockShared(long time,
 TimeUnit unit)
                   throws InterruptedException

Description copied from interface: NamedLock

Tries to lock shared, may block for given time. If successful, returns true.

Throws:

InterruptedException

lockExclusively

public boolean lockExclusively(long time,
 TimeUnit unit)
                        throws InterruptedException

Description copied from interface: NamedLock

Tries to lock exclusively, may block for given time. If successful, returns true.

Throws:

InterruptedException

unlock

public void unlock()

Description copied from interface: NamedLock

Unlocks the lock, must be invoked by caller after one of the NamedLock.lockShared(long, TimeUnit) or NamedLock.lockExclusively(long, TimeUnit).