org.apache.jackrabbit.core
Class CachingHierarchyManager

java.lang.Object
  org.apache.jackrabbit.core.HierarchyManagerImpl
      org.apache.jackrabbit.core.CachingHierarchyManager

All Implemented Interfaces:

HierarchyManager, ItemStateListener, NodeStateListener, Dumpable

public class CachingHierarchyManager
extends HierarchyManagerImpl
implements NodeStateListener, Dumpable

Implementation of a HierarchyManager that caches paths of items.

Field Summary

static int

DEFAULT_UPPER_LIMIT Default upper limit of cached states

Fields inherited from class org.apache.jackrabbit.core.HierarchyManagerImpl

provider, resolver, rootNodeId

Constructor Summary

CachingHierarchyManager(NodeId rootNodeId, ItemStateManager provider, PathResolver resolver)
Create a new instance of this class.

Method Summary

protected void	buildPath(Path.PathBuilder builder, ItemState state) Adds the path element of an item id to the path currently being built. Overridden method tries to find a mapping for the intermediate item state and add its path elements to the builder currently being used.
void	dump(PrintStream ps) Dump contents of path map and elements included to PrintStream given.
int	getDepth(ItemId id) Returns the depth of the specified item which is equivalent to getPath(id).getAncestorCount(). The depth reflects the absolute hierarchy level.
QName	getName(ItemId id) Returns the name of the specified item.
Path	getPath(ItemId id) Returns the path to the given item. Overridden method simply checks whether we have an item matching the id and returns its path, otherwise calls base implementation.
boolean	isAncestor(NodeId nodeId, ItemId itemId) Determines whether the node with the specified nodeId is an ancestor of the item denoted by the given itemId. This is equivalent to getPath(nodeId).isAncestorOf(getPath(itemId)).
void	nodeAdded(NodeState state, QName name, int index, NodeId id) Called when a child node has been added
void	nodeModified(NodeState modified) Called when a node has been modified, typically as a result of removal or addition of a child node. Evict moved or renamed items from the cache.
void	nodeRemoved(NodeState state, QName name, int index, NodeId id) Called when a child node has been removed
void	nodesReplaced(NodeState state) Called when the children nodes were replaced by other nodes, typically as result of a reorder operation. Generate subsequent add and remove notifications for every replacement.
ItemId	resolvePath(Path path) Resolves a path into an item id. Note that, for performance reasons, this method returns null rather than throwing a PathNotFoundException if there's no item to be found at path. Check the path indicated inside our cache first.
protected ItemId	resolvePath(Path path, ItemState state, int next) Resolve a path into an item id. Cache the intermediate item inside our cache.
void	stateCreated(ItemState created) Called when an ItemState has successfully been created (i.e.
void	stateDestroyed(ItemState destroyed) Called when an ItemState has successfully been removed (i.e.
void	stateDiscarded(ItemState discarded) Called when an ItemState has been discarded (i.e.
void	stateModified(ItemState modified) Called when an ItemState has successfully been modified (i.e.

Methods inherited from class org.apache.jackrabbit.core.HierarchyManagerImpl

getChildNodeEntry, getChildNodeEntry, getItemState, getParentId, getRelativeDepth, getRootNodeId, hasItemState, resolvePath, safeGetJCRPath, safeGetJCRPath

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_UPPER_LIMIT

public static final int DEFAULT_UPPER_LIMIT

Default upper limit of cached states

See Also:

Constant Field Values

Constructor Detail

CachingHierarchyManager

public CachingHierarchyManager(NodeId rootNodeId,
                               ItemStateManager provider,
                               PathResolver resolver)

Create a new instance of this class.

Parameters:

rootNodeId - root node id

provider - item state manager

resolver - namespace resolver

Method Detail

resolvePath

protected ItemId resolvePath(Path path,
                             ItemState state,
                             int next)
                      throws ItemStateException

Resolve a path into an item id. Recursively invoked method that may be overridden by some subclass to either return cached responses or add response to cache.

Cache the intermediate item inside our cache.

Overrides:

resolvePath in class HierarchyManagerImpl

Parameters:

path - full path of item to resolve

state - intermediate state

next - next path element index to resolve

Returns:

the id of the item denoted by path or null if no item exists at path.

Throws:

ItemStateException

buildPath

protected void buildPath(Path.PathBuilder builder,
                         ItemState state)
                  throws ItemStateException,
                         RepositoryException

Adds the path element of an item id to the path currently being built. Recursively invoked method that may be overridden by some subclass to either return cached responses or add response to cache. On exit, builder contains the path of state.

Overridden method tries to find a mapping for the intermediate item state and add its path elements to the builder currently being used. If no mapping is found, the item is cached instead after the base implementation has been invoked.

Overrides:

buildPath in class HierarchyManagerImpl

Parameters:

builder - builder currently being used

state - item to find path of

Throws:

ItemStateException

RepositoryException

resolvePath

public ItemId resolvePath(Path path)
                   throws RepositoryException

Resolves a path into an item id.

Note that, for performance reasons, this method returns null rather than throwing a PathNotFoundException if there's no item to be found at path.

Check the path indicated inside our cache first.

Specified by:

resolvePath in interface HierarchyManager

Overrides:

resolvePath in class HierarchyManagerImpl

Parameters:

path - path to resolve

Returns:

item id refered to by path or null if there's no item at path.

Throws:

RepositoryException - if an error occurs

getPath

public Path getPath(ItemId id)
             throws ItemNotFoundException,
                    RepositoryException

Returns the path to the given item.

Overridden method simply checks whether we have an item matching the id and returns its path, otherwise calls base implementation.

Specified by:

getPath in interface HierarchyManager

Overrides:

getPath in class HierarchyManagerImpl

Returns:

Throws:

ItemNotFoundException

RepositoryException

getName

public QName getName(ItemId id)
              throws ItemNotFoundException,
                     RepositoryException

Returns the name of the specified item.

Specified by:

getName in interface HierarchyManager

Overrides:

getName in class HierarchyManagerImpl

Parameters:

id - id of item whose name should be returned

Returns:

Throws:

ItemNotFoundException

RepositoryException

getDepth

public int getDepth(ItemId id)
             throws ItemNotFoundException,
                    RepositoryException

Returns the depth of the specified item which is equivalent to getPath(id).getAncestorCount(). The depth reflects the absolute hierarchy level.

Specified by:

getDepth in interface HierarchyManager

Overrides:

getDepth in class HierarchyManagerImpl

Parameters:

id - item id

Returns:

the depth of the specified item

Throws:

ItemNotFoundException - if the specified id does not denote an existing item.

RepositoryException - if another error occurs

isAncestor

public boolean isAncestor(NodeId nodeId,
                          ItemId itemId)
                   throws ItemNotFoundException,
                          RepositoryException

Determines whether the node with the specified nodeId is an ancestor of the item denoted by the given itemId. This is equivalent to getPath(nodeId).isAncestorOf(getPath(itemId)).

Specified by:

isAncestor in interface HierarchyManager

Overrides:

isAncestor in class HierarchyManagerImpl

Parameters:

nodeId - node id

itemId - item id

Returns:

true if the node with the specified nodeId is an ancestor of the item denoted by the given itemIdfalse otherwise

Throws:

ItemNotFoundException - if any of the specified id's does not denote an existing item.

RepositoryException - if another error occurs

stateCreated

public void stateCreated(ItemState created)

Called when an ItemState has successfully been created (i.e. its underlying persistent state was created).

Specified by:

stateCreated in interface ItemStateListener

Parameters:

created - the ItemState that has been 'created'

stateModified

public void stateModified(ItemState modified)

Called when an ItemState has successfully been modified (i.e. its underlying persistent state has changed).

Specified by:

stateModified in interface ItemStateListener

Parameters:

modified - the ItemState that has been 'modified'

nodeModified

public void nodeModified(NodeState modified)

Called when a node has been modified, typically as a result of removal or addition of a child node.

Please note, that this method is not called if ItemStateListener.stateModified(ItemState) was called. Evict moved or renamed items from the cache.

Specified by:

nodeModified in interface NodeStateListener

Parameters:

modified - node state that changed

stateDestroyed

public void stateDestroyed(ItemState destroyed)

Called when an ItemState has successfully been removed (i.e. its underlying persistent state has been destroyed).

Specified by:

stateDestroyed in interface ItemStateListener

Parameters:

destroyed - the ItemState that has been 'destroyed'

stateDiscarded

public void stateDiscarded(ItemState discarded)

Called when an ItemState has been discarded (i.e. it has been rendered 'invalid').

Specified by:

stateDiscarded in interface ItemStateListener

Parameters:

discarded - the ItemState that has been discarded

See Also:

ItemState.discard()

nodeAdded

public void nodeAdded(NodeState state,
                      QName name,
                      int index,
                      NodeId id)

Called when a child node has been added

Specified by:

nodeAdded in interface NodeStateListener

Parameters:

state - node state that changed

name - name of node that was added

index - index of new node

id - id of new node

nodesReplaced

public void nodesReplaced(NodeState state)

Called when the children nodes were replaced by other nodes, typically as result of a reorder operation.

Generate subsequent add and remove notifications for every replacement. This method currently assumes that the reordering is detectable by comparing the state's child node entries to the overlayed state's child node entries. It is not able to handle a transient reordering and will therefore evict its cached entry if such a situation is detected.

Specified by:

nodesReplaced in interface NodeStateListener

Parameters:

state - node state that changed

nodeRemoved

public void nodeRemoved(NodeState state,
                        QName name,
                        int index,
                        NodeId id)

Called when a child node has been removed

Specified by:

nodeRemoved in interface NodeStateListener

Parameters:

state - node state that changed

name - name of node that was removed

index - index of removed node

id - id of removed node

dump

public void dump(PrintStream ps)

Dump contents of path map and elements included to PrintStream given.

Specified by:

dump in interface Dumpable

Parameters:

ps - print stream to dump to