Package org.apache.lucene.store

Class VerifyingLockFactory

java.lang.Object

org.apache.lucene.store.LockFactory

org.apache.lucene.store.VerifyingLockFactory

public final class VerifyingLockFactory
extends LockFactory

A LockFactory that wraps another LockFactory and verifies that each lock obtain/release is "correct" (never results in two processes holding the lock at the same time). It does this by contacting an external server (LockVerifyServer) to assert that at most one process holds the lock at a time. To use this, you should also run LockVerifyServer on the host and port matching what you pass to the constructor.

See Also:

• LockVerifyServer
• LockStressTest

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MSG_LOCK_ACQUIRED
static final int	MSG_LOCK_RELEASED

Constructor Summary

Constructors

Constructor	Description
VerifyingLockFactory(LockFactory lf, InputStream in, OutputStream out)

Method Summary

Modifier and Type	Method	Description
Lock	obtainLock(Directory dir, String lockName)	Return a new obtained Lock instance identified by lockName.

Methods inherited from class java.lang.Object

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

Field Details

MSG_LOCK_RELEASED

public static final int MSG_LOCK_RELEASED

See Also:

• Constant Field Values

MSG_LOCK_ACQUIRED

public static final int MSG_LOCK_ACQUIRED

See Also:

• Constant Field Values

Constructor Details

VerifyingLockFactory

public VerifyingLockFactory(LockFactory lf,
 InputStream in,
 OutputStream out)
                     throws IOException

Parameters:

lf - the LockFactory that we are testing

in - the socket's input to LockVerifyServer

out - the socket's output to LockVerifyServer

Throws:

IOException

Method Details

obtainLock

public Lock obtainLock(Directory dir,
 String lockName)
                throws IOException

Description copied from class: LockFactory

Return a new obtained Lock instance identified by lockName.

Specified by:

obtainLock in class LockFactory

lockName - name of the lock to be created.

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