org.jboss.cache.loader
Class LocalDelegatingCacheLoader

java.lang.Object
  org.jboss.cache.loader.AbstractCacheLoader
      org.jboss.cache.loader.LocalDelegatingCacheLoader

All Implemented Interfaces:

CacheLoader

public class LocalDelegatingCacheLoader
extends AbstractCacheLoader

DelegatingCacheLoader implementation which delegates to a local (in the same VM) CacheImpl. Sample code:

 CacheImpl firstLevel=new CacheImpl();
 CacheImpl secondLevel=new CacheImpl();
 DelegatingCacheLoader l=new DelegatingCacheLoader(secondLevel);
 l.setCache(firstLevel);
 firstLevel.setCacheLoader(l);
 secondLevel.start();
 firstLevel.start();
 

Version:

$Id: LocalDelegatingCacheLoader.java 5103 2008-01-09 11:52:25Z manik.surtani@jboss.com $

Author:

Bela Ban, Daniel Gredler

Field Summary

Fields inherited from class org.jboss.cache.loader.AbstractCacheLoader

cache, regionManager, transactions

Constructor Summary

LocalDelegatingCacheLoader()

Method Summary

boolean	exists(Fqn name) Returns true if the CacheLoader has a node with a Fqn.
Map<Object,Object>	get(Fqn name) Returns all keys and values from the persistent store, given a Fqn
CacheLoaderConfig.IndividualCacheLoaderConfig	getConfig() Gets the configuration.
Set<?>	getChildrenNames(Fqn fqn) Returns a set of children node names.
void	loadEntireState(ObjectOutputStream os) Fetches the entire state for this cache from secondary storage (disk, database) and writes it to a provided ObjectOutputStream.
void	loadState(Fqn subtree, ObjectOutputStream os) Fetches a portion of the state for this cache from secondary storage (disk, database) and writes it to a provided ObjectOutputStream.
void	put(Fqn name, Map<Object,Object> attributes) Puts all entries of the map into the existing map of the given node, overwriting existing keys, but not clearing the existing map before insertion.
Object	put(Fqn name, Object key, Object value) Puts a key and value into the attribute map of a given node.
void	remove(Fqn fqn) Removes the given node and all its subnodes, does nothing if the node does not exist.
Object	remove(Fqn fqn, Object key) Removes the given key and value from the attributes of the given node.
void	removeData(Fqn fqn) Removes all attributes from a given node, but doesn't delete the node itself or any subnodes.
void	setConfig(CacheLoaderConfig.IndividualCacheLoaderConfig config) Sets the configuration.
protected void	setDelegateCache(CacheSPI delegate)
void	storeEntireState(ObjectInputStream is) Stores the entire state for this cache by reading it from a provided ObjectInputStream.
void	storeState(Fqn subtree, ObjectInputStream is) Stores the given portion of the cache tree's state in secondary storage.

Methods inherited from class org.jboss.cache.loader.AbstractCacheLoader

commit, create, destroy, doMarshall, doUnmarshall, getMarshaller, getNodeDataList, loadStateHelper, prepare, put, put, regionAwareMarshall, regionAwareUnmarshall, rollback, setCache, setRegionManager, start, stop

Methods inherited from class java.lang.Object

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

Constructor Detail

LocalDelegatingCacheLoader

public LocalDelegatingCacheLoader()

Method Detail

setConfig

public void setConfig(CacheLoaderConfig.IndividualCacheLoaderConfig config)

Description copied from interface: CacheLoader

Sets the configuration. This is called before CacheLoader.create() and CacheLoader.start().

Parameters:

config - May be an instance of the CacheLoaderConfig.IndividualCacheLoaderConfig base class, in which case the cache loader should use the CacheLoaderConfig.IndividualCacheLoaderConfig.getProperties() method to find configuration information. Alternatively, may be a type-specific subclass of CacheLoaderConfig.IndividualCacheLoaderConfig, if there is one.

getConfig

public CacheLoaderConfig.IndividualCacheLoaderConfig getConfig()

Description copied from interface: CacheLoader

Gets the configuration.

Returns:

the configuration, represented by a CacheLoaderConfig.IndividualCacheLoaderConfig object.

getChildrenNames

public Set<?> getChildrenNames(Fqn fqn)
                        throws Exception

Description copied from interface: CacheLoader

Returns a set of children node names. All names are relative to this parent Fqn. Returns null if the named node is not found or there are no children. The returned set must not be modifiable. Implementors can use Collections.unmodifiableSet(java.util.Set) to make the set unmodifiable.

Implementors may impose restrictions on the contents of an Fqn (such as Strings-only) and as such, indirectly impose the same restriction on the contents of a Set returned by getChildrenNames().

Parameters:

fqn - The Fqn of the parent

Returns:

Set a set of children. Returns null if no children nodes are present, or the parent is not present

Throws:

Exception

get

public Map<Object,Object> get(Fqn name)
                       throws Exception

Description copied from interface: CacheLoader

Returns all keys and values from the persistent store, given a Fqn

Parameters:

name - the Fqn to search for.

Returns:

Map keys and values for the given node. Returns null if the node is not found. If the node is found but has no attributes, this method returns an empty Map.

Throws:

Exception

exists

public boolean exists(Fqn name)
               throws Exception

Description copied from interface: CacheLoader

Returns true if the CacheLoader has a node with a Fqn.

Returns:

true if node exists, false otherwise

Throws:

Exception

put

public Object put(Fqn name,
                  Object key,
                  Object value)
           throws Exception

Description copied from interface: CacheLoader

Puts a key and value into the attribute map of a given node. If the node does not exist, all parent nodes from the root down are created automatically. Returns the old value.

Throws:

Exception

put

public void put(Fqn name,
                Map<Object,Object> attributes)
         throws Exception

Description copied from interface: CacheLoader

Puts all entries of the map into the existing map of the given node, overwriting existing keys, but not clearing the existing map before insertion. This is the same behavior as Map.putAll(java.util.Map). If the node does not exist, all parent nodes from the root down are created automatically

Parameters:

name - The fully qualified name of the node

attributes - A Map of attributes. Can be null

Throws:

Exception

remove

public Object remove(Fqn fqn,
                     Object key)
              throws Exception

Description copied from interface: CacheLoader

Removes the given key and value from the attributes of the given node. Does nothing if the node doesn't exist Returns the removed value.

Throws:

Exception

remove

public void remove(Fqn fqn)
            throws Exception

Description copied from interface: CacheLoader

Removes the given node and all its subnodes, does nothing if the node does not exist.

Parameters:

fqn - the Fqn of the node

Throws:

Exception

removeData

public void removeData(Fqn fqn)
                throws Exception

Description copied from interface: CacheLoader

Removes all attributes from a given node, but doesn't delete the node itself or any subnodes.

Parameters:

fqn - the Fqn of the node

Throws:

Exception

setDelegateCache

protected void setDelegateCache(CacheSPI delegate)

loadEntireState

public void loadEntireState(ObjectOutputStream os)
                     throws Exception

Description copied from interface: CacheLoader

Fetches the entire state for this cache from secondary storage (disk, database) and writes it to a provided ObjectOutputStream. State written to the provided ObjectOutputStream parameter is used for initialization of a new CacheImpl instance. When the state gets transferred to the new cache instance its cacheloader calls CacheLoader.storeEntireState(ObjectInputStream)

Implementations of this method should not catch any exception or close the given ObjectOutputStream parameter. In order to ensure cacheloader interoperability contents of the cache are written to the ObjectOutputStream as a sequence of NodeData objects.

Default implementation is provided by AbstractCacheLoader and ensures cacheloader interoperability. Implementors are encouraged to consider extending AbstractCacheLoader prior to implementing completely custom cacheloader.

Specified by:

loadEntireState in interface CacheLoader

Overrides:

loadEntireState in class AbstractCacheLoader

Parameters:

os - ObjectOutputStream to write state

Throws:

Exception

See Also:

AbstractCacheLoader.loadEntireState(ObjectOutputStream), NodeData

loadState

public void loadState(Fqn subtree,
                      ObjectOutputStream os)
               throws Exception

Description copied from interface: CacheLoader

Fetches a portion of the state for this cache from secondary storage (disk, database) and writes it to a provided ObjectOutputStream. State written to the provided ObjectOutputStream parameter is used for activation of a portion of a new CacheImpl instance. When the state gets transferred to the new cache instance its cacheloader calls CacheLoader.storeState(Fqn,ObjectInputStream).

Implementations of this method should not catch any exception or close the given ObjectOutputStream parameter. In order to ensure cacheloader interoperability contents of the cache are written to the ObjectOutputStream as a sequence of NodeData objects.

Default implementation is provided by AbstractCacheLoader and ensures cacheloader interoperability. Implementors are encouraged to consider extending AbstractCacheLoader prior to implementing completely custom cacheloader.

Specified by:

loadState in interface CacheLoader

Overrides:

loadState in class AbstractCacheLoader

Parameters:

subtree - Fqn naming the root (i.e. highest level parent) node of the subtree for which state is requested.

os - ObjectOutputStream to write state

Throws:

Exception

See Also:

AbstractCacheLoader.loadState(Fqn,ObjectOutputStream), Region.activate(), NodeData

storeEntireState

public void storeEntireState(ObjectInputStream is)
                      throws Exception

Description copied from interface: CacheLoader

Stores the entire state for this cache by reading it from a provided ObjectInputStream. The state was provided to this cache by calling CacheLoader.loadEntireState(ObjectOutputStream)} on some other cache instance. State currently in storage gets overwritten.

Implementations of this method should not catch any exception or close the given ObjectInputStream parameter. In order to ensure cacheloader interoperability contents of the cache are read from the ObjectInputStream as a sequence of NodeData objects.

Default implementation is provided by AbstractCacheLoader and ensures cacheloader interoperability. Implementors are encouraged to consider extending AbstractCacheLoader prior to implementing completely custom cacheloader.

Specified by:

storeEntireState in interface CacheLoader

Overrides:

storeEntireState in class AbstractCacheLoader

Parameters:

is - ObjectInputStream to read state

Throws:

Exception

See Also:

AbstractCacheLoader.storeEntireState(ObjectInputStream), NodeData

storeState

public void storeState(Fqn subtree,
                       ObjectInputStream is)
                throws Exception

Description copied from interface: CacheLoader

Stores the given portion of the cache tree's state in secondary storage. Overwrite whatever is currently in secondary storage. If the transferred state has Fqns equal to or children of parameter subtree, then no special behavior is required. Otherwise, ensure that the state is integrated under the given subtree. Typically in the latter case subtree would be the Fqn of the buddy backup region for a buddy group; e.g.

If the the transferred state had Fqns starting with "/a" and subtree was "/_BUDDY_BACKUP_/192.168.1.2:5555" then the state should be stored in the local persistent store under "/_BUDDY_BACKUP_/192.168.1.2:5555/a"

Implementations of this method should not catch any exception or close the given ObjectInputStream parameter. In order to ensure cacheloader interoperability contents of the cache are read from the ObjectInputStream as a sequence of NodeData objects.

Default implementation is provided by AbstractCacheLoader and ensures cacheloader interoperability. Implementors are encouraged to consider extending AbstractCacheLoader prior to implementing completely custom cacheloader.

Specified by:

storeState in interface CacheLoader

Overrides:

storeState in class AbstractCacheLoader

Parameters:

subtree - Fqn naming the root (i.e. highest level parent) node of the subtree included in state. If the Fqns of the data included in state are not already children of subtree, then their Fqns should be altered to make them children of subtree before they are persisted.

is - ObjectInputStream to read state

Throws:

Exception

See Also:

AbstractCacheLoader.storeState(Fqn,ObjectInputStream), NodeData