Package org.apache.lucene.store

Class Lock

java.lang.Object

org.apache.lucene.store.Lock

All Implemented Interfaces:

Closeable, AutoCloseable

public abstract class Lock
extends Object
implements Closeable

An interprocess mutex lock.

Typical use might look like:

   try (final Lock lock = directory.obtainLock("my.lock")) {
     // ... code to execute while locked ...
   }
 

See Also:

• Directory.obtainLock(String)

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Constructor Summary

Constructors

Constructor	Description
Lock()

Method Summary

Modifier and Type	Method	Description
abstract void	close()	Releases exclusive access.
abstract void	ensureValid()	Best effort check that this lock is still valid.

Methods inherited from class java.lang.Object

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

Constructor Details

Lock

public Lock()

Method Details

close

public abstract void close()
                    throws IOException

Releases exclusive access.

Note that exceptions thrown from close may require human intervention, as it may mean the lock was no longer valid, or that fs permissions prevent removal of the lock file, or other reasons.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

LockReleaseFailedException - optional specific exception) if the lock could not be properly released.

IOException

ensureValid

public abstract void ensureValid()
                          throws IOException

Best effort check that this lock is still valid. Locks could become invalidated externally for a number of reasons, for example if a user deletes the lock file manually or when a network filesystem is in use.

Throws:

IOException - if the lock is no longer valid.