Package org.apache.lucene.store

Class SleepingLockWrapper

java.lang.Object

org.apache.lucene.store.Directory

org.apache.lucene.store.FilterDirectory

org.apache.lucene.store.SleepingLockWrapper

All Implemented Interfaces:

Closeable, AutoCloseable

public final class SleepingLockWrapper
extends FilterDirectory

Directory that wraps another, and that sleeps and retries if obtaining the lock fails.

This is not a good idea.

Field Summary

Fields

Modifier and Type	Field	Description
static long	DEFAULT_POLL_INTERVAL	How long obtainLock(java.lang.String) waits, in milliseconds, in between attempts to acquire the lock.
static final long	LOCK_OBTAIN_WAIT_FOREVER	Pass this lockWaitTimeout to try forever to obtain the lock.

Fields inherited from class org.apache.lucene.store.FilterDirectory

in

Constructor Summary

Constructors

Constructor	Description
SleepingLockWrapper(Directory delegate, long lockWaitTimeout)	Create a new SleepingLockFactory
SleepingLockWrapper(Directory delegate, long lockWaitTimeout, long pollInterval)	Create a new SleepingLockFactory

Method Summary

Modifier and Type	Method	Description
Lock	obtainLock(String lockName)	Acquires and returns a Lock for a file with the given name.
String	toString()

Methods inherited from class org.apache.lucene.store.FilterDirectory

close, createOutput, createTempOutput, deleteFile, ensureOpen, fileLength, getDelegate, getPendingDeletions, listAll, openInput, rename, sync, syncMetaData, unwrap

Methods inherited from class org.apache.lucene.store.Directory

copyFrom, getTempFileName, openChecksumInput

Methods inherited from class java.lang.Object

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

Field Details

LOCK_OBTAIN_WAIT_FOREVER

public static final long LOCK_OBTAIN_WAIT_FOREVER

Pass this lockWaitTimeout to try forever to obtain the lock.

See Also:

• Constant Field Values

DEFAULT_POLL_INTERVAL

public static long DEFAULT_POLL_INTERVAL

How long obtainLock(java.lang.String) waits, in milliseconds, in between attempts to acquire the lock.

Constructor Details

SleepingLockWrapper

public SleepingLockWrapper(Directory delegate,
 long lockWaitTimeout)

Create a new SleepingLockFactory

Parameters:

delegate - underlying directory to wrap

lockWaitTimeout - length of time to wait in milliseconds or LOCK_OBTAIN_WAIT_FOREVER to retry forever.

SleepingLockWrapper

public SleepingLockWrapper(Directory delegate,
 long lockWaitTimeout,
 long pollInterval)

Create a new SleepingLockFactory

Parameters:

delegate - underlying directory to wrap

lockWaitTimeout - length of time to wait in milliseconds or LOCK_OBTAIN_WAIT_FOREVER to retry forever.

pollInterval - poll once per this interval in milliseconds until lockWaitTimeout is exceeded.

Method Details

obtainLock

public Lock obtainLock(String lockName)
                throws IOException

Description copied from class: Directory

Acquires and returns a Lock for a file with the given name.

Overrides:

obtainLock in class FilterDirectory

Parameters:

lockName - the name of the lock file

Throws:

LockObtainFailedException - (optional specific exception) if the lock could not be obtained because it is currently held elsewhere.

IOException - if any i/o error occurs attempting to gain the lock

toString

public String toString()

Overrides:

toString in class FilterDirectory