org.apache.openjpa.datacache
Class PartitionedDataCache

java.lang.Object
  extended by org.apache.openjpa.lib.util.concurrent.AbstractConcurrentEventManager
      extended by org.apache.openjpa.datacache.AbstractDataCache
          extended by org.apache.openjpa.datacache.ConcurrentDataCache
              extended by org.apache.openjpa.datacache.PartitionedDataCache
All Implemented Interfaces:
Serializable, DataCache, RemoteCommitListener, Configurable, Clearable, Closeable, EventManager

public class PartitionedDataCache
extends ConcurrentDataCache

A partitioned data cache maintains a set of partitions that are DataCache themselves. Each of the partitioned DataCaches can be individually configured. However, all partitions must be of the same type. By default, this cache uses ConcurrentDataCache as its partitions.
This cache can be configured as a plug-in as follows:
<property name='openjpa.DataCache" value="partitioned(name=X, PartitionType=concurrent,Partitions='(name=a,cacheSize=100), (name=b,cacheSize=200)')
Notice that the individual partition properties are enclosed parentheses, separated by comma and finally the whole property string is enclosed in single quote. Each partition must have a non-empty name that are unique among the partitions. The policy can return the name of a partition to distribute the managed instances to be cached in respective partition. The above configuration will configure a partitioned cache named X with two partitions named a and b with cache size 100 and 200 respectively. Besides the two partitions, this cache instance itself can store data and referred by its own name (X in the above example).

Since:
2.0.0
Author:
Pinaki Poddar
See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.apache.openjpa.datacache.ConcurrentDataCache
_lru
 
Fields inherited from class org.apache.openjpa.datacache.AbstractDataCache
_evictOnBulkUpdate, _excludedTypes, _includedTypes, _stats, conf, log
 
Fields inherited from class org.apache.openjpa.lib.util.concurrent.AbstractConcurrentEventManager
_listeners
 
Fields inherited from interface org.apache.openjpa.datacache.DataCache
NAME_DEFAULT
 
Constructor Summary
PartitionedDataCache()
           
 
Method Summary
 void endConfiguration()
          Invoked upon completion of bean property configuration for this object.
 DataCache getPartition(String name, boolean create)
          Gets the named partition.
 Set<String> getPartitionNames()
          Gets the name of the configured partitions.
 List<String> getPartitions()
          Returns the individual partition configuration properties.
 void initialize(DataCacheManager mgr)
          Initialize any resources associated with the given DataCacheManager.
 boolean isPartitioned()
          Always returns true.
 void setPartitions(String parts)
          Set partitions from a String configuration.
 void setPartitionType(String type)
          Sets the type of the partitions.
 
Methods inherited from class org.apache.openjpa.datacache.ConcurrentDataCache
clearInternal, getCacheMap, getCacheSize, getInternal, getLru, getSoftReferenceSize, newCacheMap, pinInternal, putInternal, recacheUpdates, removeAllInternal, removeInternal, setCacheSize, setLru, setSoftReferenceSize, unpinAll, unpinInternal, writeLock, writeUnlock
 
Methods inherited from class org.apache.openjpa.datacache.AbstractDataCache
addExpirationListener, afterCommit, clear, close, close, commit, contains, containsAll, fireEvent, get, getAll, getEnableStatistics, getEvictionSchedule, getEvictOnBulkUpdate, getExcludedTypes, getName, getStatistics, getTypes, isClosed, keyRemoved, pin, pinAll, pinAll, put, putAllInternal, remove, removeAll, removeAll, removeAllInternal, removeAllTypeNamesInternal, removeExpirationListener, selectCache, setConfiguration, setEnableStatistics, setEvictionSchedule, setEvictOnBulkUpdate, setExcludedTypes, setExcludedTypes, setName, setTypes, setTypes, startConfiguration, toString, unpin, unpinAll, update
 
Methods inherited from class org.apache.openjpa.lib.util.concurrent.AbstractConcurrentEventManager
addListener, fireEvent, getListeners, hasListener, hasListeners, isFailFast, newListenerCollection, removeListener, setFailFast
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.apache.openjpa.event.RemoteCommitListener
afterCommit, close
 

Constructor Detail

PartitionedDataCache

public PartitionedDataCache()
Method Detail

initialize

public void initialize(DataCacheManager mgr)
Description copied from interface: DataCache
Initialize any resources associated with the given DataCacheManager.

Specified by:
initialize in interface DataCache
Overrides:
initialize in class ConcurrentDataCache

setPartitionType

public void setPartitionType(String type)
                      throws Exception
Sets the type of the partitions. Each partition is a DataCache itself.

Parameters:
type - the name of the type that implements DataCache interface. Aliases such as "concurrent" is also recognized.
Throws:
Exception - if the given type is not resolvable to a loadable type.

setPartitions

public void setPartitions(String parts)
Set partitions from a String configuration.

Parameters:
parts - a String of the form (p1, p2, p3) where p1, p2 etc. itself are plug-in strings for individual Data Cache configuration.

getPartitions

public List<String> getPartitions()
Returns the individual partition configuration properties.


getPartition

public DataCache getPartition(String name,
                              boolean create)
Description copied from interface: DataCache
Gets the named partition. Note that a partition itself is another cache.

Specified by:
getPartition in interface DataCache
Overrides:
getPartition in class AbstractDataCache
Parameters:
name - name of the given partition.
create - if true optionally create a new partition.
Returns:
a partition of the given name. Or null, if either no such partition exists or can not be created.

getPartitionNames

public Set<String> getPartitionNames()
Gets the name of the configured partitions.

Specified by:
getPartitionNames in interface DataCache
Overrides:
getPartitionNames in class AbstractDataCache
Returns:
empty set if no partition exists.

isPartitioned

public final boolean isPartitioned()
Always returns true.

Specified by:
isPartitioned in interface DataCache
Overrides:
isPartitioned in class AbstractDataCache

endConfiguration

public void endConfiguration()
Description copied from interface: Configurable
Invoked upon completion of bean property configuration for this object.

Specified by:
endConfiguration in interface Configurable
Overrides:
endConfiguration in class AbstractDataCache


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