org.pentaho.platform.plugin.services.cache

Class CacheManager

java.lang.Object

org.pentaho.platform.plugin.services.cache.CacheManager

All Implemented Interfaces:

org.pentaho.platform.api.engine.ICacheManager, org.pentaho.platform.api.engine.ILogoutListener

public class CacheManager
extends Object
implements org.pentaho.platform.api.engine.ICacheManager

This class provides an access point for pluggable caching mechanisms. Right now, it only supports the caching mechanisms implemented in org.hibernate.cache.

To use the cache manager, you need to include the following information in your pentaho.xml.

 
  <cache-provider>
    <class>org.hibernate.cache.xxxxxxxx</class>
    <region>pentahoCache</region>
    <properties>
      <property name="someProperty">someValue</property>
    </properties>
  </cache-provider>
 

The specified class must implement the org.hibernate.cache.CacheProvider interface.

Each implementation of the org.hibernate.cache.CacheProvider has slightly different requirements with respect to the required input parameters - so, please see the classes in that package for more information (available from the Sourceforge Hibernate project). Also, some cache providers (notably the org.hibernate.cache.EhCacheProvider) completely ignore the passed in properties, and only configure themselves by locating a configuration file (e.g. ehcache.xml) on the classpath.

The cache manager supports session-based caching (that is, caching of data that is user-specific) as well as global-based caching (that is, caching of data that is system-wide). To differentiate between session-based and global-based caching, there are different methods that get called depending upon the storage type.

Data that is cached for user sessions require an IPentahoSession object to be passed in. The cache manager uses the IPentahoSession.getId() to classify saved objects underneath a specific user session. No information is actually stored in the user session object. For an example of this, see
putInSessionCache(IPentahoSession session, String key, Object value)

Data that is server-wide (i.e. global) uses different methods for storage/retrieval/management. For an example of this, see
getFromGlobalCache(Object key)

Example Usage:

 String globalCachable = "String to cache";
 String globalCacheKey = "StringKey";
 CacheManager cacheManager = PentahoSystem.getCacheManager();
 cacheManager.putInGlobalCache( globalCacheKey, globalCachable );
 

Important Considerations

• Most caches require objects that go into the cache as well as their respective object key implement Serializable. It is a safe assumption that both the Key and the Value should implement Serializable.
• Some caches are read-only. Other caches are read-write. What does this mean? It means that once you put an object in the cache, you can't put an object into the cache with the same key. You'd need to remove it first

Author:

mbatchel

See Also:

CacheProvider, Cache

Field Summary

Fields inherited from interface org.pentaho.platform.api.engine.ICacheManager

GLOBAL, SESSION

Constructor Summary

Constructors

Constructor and Description
CacheManager() The constructor performs the following tasks:

Method Summary

Modifier and Type	Method and Description
boolean	addCacheRegion(String region)
boolean	addCacheRegion(String region, Properties cacheProperties)
boolean	cacheEnabled()
boolean	cacheEnabled(String region)
void	cacheStop()
void	clearCache()
void	clearRegionCache(String region)
Set	getAllEntriesFromRegionCache(String region)
Set	getAllKeysFromRegionCache(String region)
List	getAllValuesFromRegionCache(String region)
long	getElementCountInGlobalCache()
long	getElementCountInRegionCache(String region)
long	getElementCountInSessionCache()
Object	getFromGlobalCache(Object key)
Object	getFromRegionCache(String region, Object key)
Object	getFromSessionCache(org.pentaho.platform.api.engine.IPentahoSession session, String key)
void	killSessionCache(org.pentaho.platform.api.engine.IPentahoSession session)
void	killSessionCaches()
void	onLogout(org.pentaho.platform.api.engine.IPentahoSession session)
void	putInGlobalCache(Object key, Object value)
void	putInRegionCache(String region, Object key, Object value)
void	putInSessionCache(org.pentaho.platform.api.engine.IPentahoSession session, String key, Object value)
void	removeFromGlobalCache(Object key)
void	removeFromRegionCache(String region, Object key)
void	removeFromSessionCache(org.pentaho.platform.api.engine.IPentahoSession session, String key)
void	removeRegionCache(String region)

Methods inherited from class java.lang.Object

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

Constructor Detail

CacheManager

public CacheManager()

The constructor performs the following tasks:

• Gets the Pentaho System Settings
• Reads the cache-provider/class element.
• Reads the cache-provider/region element.
• Reads in any properties under cache-provider/properties/*
• Attempts to instance the cache provider classes specified
• Starts the cache (see the org.hibernate.cache.CacheProvider interface)
• Calls the buildCache method (see the org.hibernate.cache.CacheProvider interface)

Method Detail

cacheStop

public void cacheStop()

Specified by:

cacheStop in interface org.pentaho.platform.api.engine.ICacheManager

cacheEnabled

public boolean cacheEnabled(String region)

Specified by:

cacheEnabled in interface org.pentaho.platform.api.engine.ICacheManager

onLogout

public void onLogout(org.pentaho.platform.api.engine.IPentahoSession session)

Specified by:

onLogout in interface org.pentaho.platform.api.engine.ICacheManager

Specified by:

onLogout in interface org.pentaho.platform.api.engine.ILogoutListener

addCacheRegion

public boolean addCacheRegion(String region,
                              Properties cacheProperties)

Specified by:

addCacheRegion in interface org.pentaho.platform.api.engine.ICacheManager

addCacheRegion

public boolean addCacheRegion(String region)

Specified by:

addCacheRegion in interface org.pentaho.platform.api.engine.ICacheManager

clearRegionCache

public void clearRegionCache(String region)

Specified by:

clearRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

removeRegionCache

public void removeRegionCache(String region)

Specified by:

removeRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

putInRegionCache

public void putInRegionCache(String region,
                             Object key,
                             Object value)

Specified by:

putInRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

getFromRegionCache

public Object getFromRegionCache(String region,
                                 Object key)

Specified by:

getFromRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

getAllValuesFromRegionCache

public List getAllValuesFromRegionCache(String region)

Specified by:

getAllValuesFromRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

getAllKeysFromRegionCache

public Set getAllKeysFromRegionCache(String region)

Specified by:

getAllKeysFromRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

getAllEntriesFromRegionCache

public Set getAllEntriesFromRegionCache(String region)

Specified by:

getAllEntriesFromRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

removeFromRegionCache

public void removeFromRegionCache(String region,
                                  Object key)

Specified by:

removeFromRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

cacheEnabled

public boolean cacheEnabled()

Specified by:

cacheEnabled in interface org.pentaho.platform.api.engine.ICacheManager

clearCache

public void clearCache()

Specified by:

clearCache in interface org.pentaho.platform.api.engine.ICacheManager

getFromGlobalCache

public Object getFromGlobalCache(Object key)

Specified by:

getFromGlobalCache in interface org.pentaho.platform.api.engine.ICacheManager

getFromSessionCache

public Object getFromSessionCache(org.pentaho.platform.api.engine.IPentahoSession session,
                                  String key)

Specified by:

getFromSessionCache in interface org.pentaho.platform.api.engine.ICacheManager

killSessionCache

public void killSessionCache(org.pentaho.platform.api.engine.IPentahoSession session)

Specified by:

killSessionCache in interface org.pentaho.platform.api.engine.ICacheManager

killSessionCaches

public void killSessionCaches()

Specified by:

killSessionCaches in interface org.pentaho.platform.api.engine.ICacheManager

putInGlobalCache

public void putInGlobalCache(Object key,
                             Object value)

Specified by:

putInGlobalCache in interface org.pentaho.platform.api.engine.ICacheManager

putInSessionCache

public void putInSessionCache(org.pentaho.platform.api.engine.IPentahoSession session,
                              String key,
                              Object value)

Specified by:

putInSessionCache in interface org.pentaho.platform.api.engine.ICacheManager

removeFromGlobalCache

public void removeFromGlobalCache(Object key)

Specified by:

removeFromGlobalCache in interface org.pentaho.platform.api.engine.ICacheManager

removeFromSessionCache

public void removeFromSessionCache(org.pentaho.platform.api.engine.IPentahoSession session,
                                   String key)

Specified by:

removeFromSessionCache in interface org.pentaho.platform.api.engine.ICacheManager

getElementCountInRegionCache

public long getElementCountInRegionCache(String region)

Specified by:

getElementCountInRegionCache in interface org.pentaho.platform.api.engine.ICacheManager

getElementCountInSessionCache

public long getElementCountInSessionCache()

Specified by:

getElementCountInSessionCache in interface org.pentaho.platform.api.engine.ICacheManager

getElementCountInGlobalCache

public long getElementCountInGlobalCache()

Specified by:

getElementCountInGlobalCache in interface org.pentaho.platform.api.engine.ICacheManager