net.sf.ehcache.concurrent

Class ConcurrencyUtil

java.lang.Object

net.sf.ehcache.concurrent.ConcurrencyUtil

public final class ConcurrencyUtil
extends Object

Various bits of black magic garnered from experts on the concurrency-interest@cs.oswego.edu mailing list.

Version:

$Id$

Author:

Greg Luck

Method Summary

Modifier and Type	Method and Description
static int	hash(Object object) Returns a hash code for non-null Object x.
static int	selectLock(Object key, int numberOfLocks) Selects a lock for a key.
static void	shutdownAndWaitForTermination(ExecutorService pool, int waitSeconds) Properly shutdown and await pool termination for an arbitrary amount of time.

Methods inherited from class java.lang.Object

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

Method Detail

hash

public static int hash(Object object)

Returns a hash code for non-null Object x.

This function ensures that hashCodes that differ only by constant multiples at each bit position have a bounded number of collisions. (Doug Lea)

Parameters:

object - the object serving as a key

Returns:

the hash code

selectLock

public static int selectLock(Object key,
                             int numberOfLocks)
                      throws CacheException

Selects a lock for a key. The same lock is always used for a given key.

Parameters:

key -

Returns:

the selected lock index

Throws:

CacheException

shutdownAndWaitForTermination

public static void shutdownAndWaitForTermination(ExecutorService pool,
                                                 int waitSeconds)
                                          throws TimeoutException

Properly shutdown and await pool termination for an arbitrary amount of time.

Parameters:

pool - Pool to shutdown

waitSeconds - Seconds to wait before throwing exception

Throws:

TimeoutException - Thrown if the pool does not shutdown in the specified time