Class PartitionedDataCache

  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).

Pinaki Poddar
See Also:
Serialized Form

Field Summary
Fields inherited from class org.apache.openjpa.datacache.AbstractDataCache
_excludedTypes, _includedTypes, conf, log, stats
Fields inherited from class org.apache.openjpa.lib.util.concurrent.AbstractConcurrentEventManager
Fields inherited from interface org.apache.openjpa.datacache.DataCache
Constructor Summary
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.
 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, getSoftReferenceSize, initialize, newCacheMap, pinInternal, putInternal, removeAllInternal, removeInternal, setCacheSize, 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, getExcludedTypes, getName, getStatistics, getTypes, isClosed, keyRemoved, pin, pinAll, pinAll, put, putAllInternal, recacheUpdates, remove, removeAll, removeAll, removeAllInternal, removeAllTypeNamesInternal, removeExpirationListener, setConfiguration, setEnableStatistics, setEvictionSchedule, 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


public PartitionedDataCache()
Method Detail


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

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


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

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


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


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
getPartition in class AbstractDataCache
name - name of the given partition.
create - if true optionally create a new partition.
a partition of the given name. Or null, if either no such partition exists or can not be created.


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

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


public final boolean isPartitioned()
Always returns true.

Specified by:
isPartitioned in interface DataCache
isPartitioned in class AbstractDataCache


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

Specified by:
endConfiguration in interface Configurable
endConfiguration in class AbstractDataCache

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