com.googlecode.hibernate.memcached
Class MemcachedCacheProvider

java.lang.Object
  com.googlecode.hibernate.memcached.MemcachedCacheProvider

All Implemented Interfaces:

org.hibernate.cache.CacheProvider

public class MemcachedCacheProvider
extends Object
implements org.hibernate.cache.CacheProvider

Configures an instance of MemcachedCache for use as a second-level cache in Hibernate. To use set the hibernate property hibernate.cache.provider_class to the name of this class.

There are two types of property settings that the MemcachedCacheProvider supports, cache-wide properties and region-name properties.

Cache wide properties

Property	Default	Description
hibernate.memcached.servers	localhost:11211	Space delimited list of memcached instances in host:port format
hibernate.memcached.cacheTimeSeconds	300	The default number of seconds items should be cached. Can be overriden at the regon level.
hibernate.memcached.keyStrategy	Sha1KeyStrategy	Sets the strategy class to to use for generating cache keys. Must provide a class name that implements KeyStrategy
hibernate.memcached.readBufferSize	DefaultConnectionFactory.DEFAULT_READ_BUFFER_SIZE	The read buffer size for each server connection from this factory
hibernate.memcached.operationQueueLength	DefaultConnectionFactory.DEFAULT_OP_QUEUE_LEN	Maximum length of the operation queue returned by this connection factory
hibernate.memcached.operationTimeout	DefaultConnectionFactory.DEFAULT_OPERATION_TIMEOUT	Default operation timeout in milliseconds
hibernate.memcached.hashAlgorithm	HashAlgorithm.KETAMA_HASH	Which hash algorithm to use when adding items to the cache. Note: the MemcachedClient defaults to using HashAlgorithm.NATIVE_HASH, while the hibernate-memcached cache defaults to KETAMA_HASH for "consistent hashing"
hibernate.memcached.clearSupported	false	Enables support for the MemcachedCache.clear() method for all cache regions. The way clear is implemented for memcached is expensive and adds overhead to all get/set operations. It is not recommended for production use.

Cache Region properties
Cache regon properties are set by giving your cached data a "region name" in hibernate. You can tune the MemcachedCache instance for your region using the following properties. These properties essentially override the cache-wide properties above.

Property	Default	Description
hibernate.memcached.[region-name].cacheTimeSeconds	none, see hibernate.memcached.cacheTimeSeconds	Set the cache time for this cache region, overriding the cache-wide setting.
hibernate.memcached.[region-name].keyStrategy	none, see hibernate.memcached.keyStrategy	Overrides the strategy class to to use for generating cache keys in this cache region. Must provide a class name that implements KeyStrategy
hibernate.memcached.[region-name].clearSupported	none, see hibernate.memcached.clearSupported	Enables clear() operations for this cache region only. Again, the clear operation incurs cost on every get/set operation.

Author:

Ray Krueger

Constructor Summary

MemcachedCacheProvider()

Method Summary

org.hibernate.cache.Cache	buildCache(String regionName, Properties properties)
protected MemcacheClientFactory	getMemcachedClientFactory(Config config)
protected KeyStrategy	instantiateKeyStrategy(String cls)
boolean	isMinimalPutsEnabledByDefault() According to the hibernate reference docs, MinimalPutsEnabledByDefault should be true for distributed caches.
long	nextTimestamp() No clue what this is for, Hibernate docs don't say.
void	start(Properties properties)
void	stop()

Methods inherited from class java.lang.Object

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

Constructor Detail

MemcachedCacheProvider

public MemcachedCacheProvider()

Method Detail

buildCache

public org.hibernate.cache.Cache buildCache(String regionName,
                                            Properties properties)
                                     throws org.hibernate.cache.CacheException

Specified by:

buildCache in interface org.hibernate.cache.CacheProvider

Throws:

org.hibernate.cache.CacheException

instantiateKeyStrategy

protected KeyStrategy instantiateKeyStrategy(String cls)

nextTimestamp

public long nextTimestamp()

No clue what this is for, Hibernate docs don't say.

Specified by:

nextTimestamp in interface org.hibernate.cache.CacheProvider

Returns:

long Timestamper.next()

start

public void start(Properties properties)
           throws org.hibernate.cache.CacheException

Specified by:

start in interface org.hibernate.cache.CacheProvider

Throws:

org.hibernate.cache.CacheException

getMemcachedClientFactory

protected MemcacheClientFactory getMemcachedClientFactory(Config config)

stop

public void stop()

Specified by:

stop in interface org.hibernate.cache.CacheProvider

isMinimalPutsEnabledByDefault

public boolean isMinimalPutsEnabledByDefault()

According to the hibernate reference docs, MinimalPutsEnabledByDefault should be true for distributed caches.

Specified by:

isMinimalPutsEnabledByDefault in interface org.hibernate.cache.CacheProvider

Returns:

true