org.jboss.cache
Class DataContainer

java.lang.Object
  org.jboss.cache.DataContainer

public class DataContainer
extends Object

A container for the root node in the cache, which also provides helpers for efficiently accessing nodes, walking trees, etc.

Since:

2.2

Author:

Mircea.Markus@jboss.com

Constructor Summary

DataContainer()

Method Summary

List<NodeData>	buildNodeData(List<NodeData> list, NodeSPI node) Prepares a list of NodeData objects for a specified node and all its children.
Object[]	createNodes(Fqn fqn) Traverses the tree to the given Fqn, creating nodes if needed.
void	createNodesLocally(Fqn<?> fqn, Map<?,?> data)
boolean	evict(Fqn fqn)
void	evict(Fqn fqn, boolean recursive)
boolean	exists(Fqn fqn) Tests if an Fqn exists and is valid and not deleted.
Set<Fqn>	getInternalFqns() Returns a Set of Fqns of the topmost node of internal regions that should not included in standard state transfers.
List<Fqn>	getNodesForEviction(Fqn fqn, boolean recursive) Generates a list of nodes for eviction.
int	getNumberOfAttributes() Returns an approximation of the total number of attributes in the cache.
int	getNumberOfAttributes(Fqn fqn) Returns an approximation of the total number of attributes in this sub cache.
int	getNumberOfLocksHeld() Returns the number of read or write locks held across the entire cache.
int	getNumberOfNodes() Returns an approximation of the total number of nodes in the cache.
NodeSPI	getRoot() Retrieves the root node.
boolean	hasChildren(Fqn fqn) Returns true if the Fqn exists, is valid and is not deleted, and the node has children.
void	injectDependencies(Configuration configuration)
NodeSPI	peek(Fqn fqn) Finds a node given a fully qualified name, directly off the interceptor chain.
NodeSPI	peek(Fqn<?> fqn, boolean includeDeletedNodes) Same as calling peek(fqn, includeDeletedNodes, false).
NodeSPI	peek(Fqn<?> fqn, boolean includeDeletedNodes, boolean includeInvalidNodes) Peeks for a specified node.
NodeSPI	peek(Fqn fqn, DataVersion version) Finds a node given a fully qualified name and DataVersion.
NodeSPI	peek(Fqn fqn, DataVersion version, boolean includeInvalidNodes) Searches for a specific node, with a specific data version and, optionally, invalid nodes as well, but not deleted nodes.
NodeSPI	peekStrict(GlobalTransaction gtx, Fqn fqn, boolean includeInvalid) Similar to peek(Fqn, org.jboss.cache.optimistic.DataVersion) except that it throws a NodeNotExistsException if the node cannot be found.
String	printDetails() Prints information about the contents of the nodes in the cache's current in-memory state.
String	printLockInfo() Returns lock information.
void	registerInternalFqn(Fqn fqn) Adds the specified Fqn to the list of Fqns to be considered "internal".
protected void	removeData(Fqn fqn)
boolean	removeFromDataStructure(Fqn f, boolean skipMarkerCheck) Removes the actual node from the tree data structure.
void	setRoot(NodeSPI root) Sets the root node reference to the node passed in.
String	toString()
String	toString(boolean details) Returns a debug string with optional details of contents.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataContainer

public DataContainer()

Method Detail

injectDependencies

public void injectDependencies(Configuration configuration)

getRoot

public NodeSPI getRoot()

Retrieves the root node.

Returns:

the root node

setRoot

public void setRoot(NodeSPI root)

Sets the root node reference to the node passed in.

Parameters:

root - node

registerInternalFqn

public void registerInternalFqn(Fqn fqn)

Adds the specified Fqn to the list of Fqns to be considered "internal".

Parameters:

fqn - fqn to add to list

peek

public NodeSPI peek(Fqn fqn)

Finds a node given a fully qualified name, directly off the interceptor chain. In the event of an exception, returns null. Does not include invalid or deleted nodes.

Parameters:

fqn - Fully qualified name for the corresponding node.

Returns:

Node referenced by the given Fqn, or null if the node cannot be found or if there is an exception.

peek

public NodeSPI peek(Fqn fqn,
                    DataVersion version)

Finds a node given a fully qualified name and DataVersion. Does not include invalid or deleted nodes. If the data version passed in is null, then data version checking is skipped. Data version checking is also skipped if optimistic locking is not used.

Parameters:

fqn - fqn to find

version - version of the node to find

Returns:

a node, if found, or null if not.

peekStrict

public NodeSPI peekStrict(GlobalTransaction gtx,
                          Fqn fqn,
                          boolean includeInvalid)

Similar to peek(Fqn, org.jboss.cache.optimistic.DataVersion) except that it throws a NodeNotExistsException if the node cannot be found.

Parameters:

gtx - global transaction

fqn - fqn to find

includeInvalid - if true, invalid nodes are considered as well.

Returns:

the node

peek

public NodeSPI peek(Fqn fqn,
                    DataVersion version,
                    boolean includeInvalidNodes)

Searches for a specific node, with a specific data version and, optionally, invalid nodes as well, but not deleted nodes. If the data version passed in is null, then data version checking is skipped. Data version checking is also skipped if optimistic locking is not used.

Parameters:

fqn - Fqn to find

version - version of the node to find

includeInvalidNodes - if true, invalid nodes are considered

Returns:

the node, if found, or null otherwise.

peek

public NodeSPI peek(Fqn<?> fqn,
                    boolean includeDeletedNodes)

Same as calling peek(fqn, includeDeletedNodes, false).

Parameters:

fqn - Fqn to find

includeDeletedNodes - if true, deleted nodes are considered

Returns:

the node, if found, or null otherwise.

peek

public NodeSPI peek(Fqn<?> fqn,
                    boolean includeDeletedNodes,
                    boolean includeInvalidNodes)

Peeks for a specified node. This involves a direct walk of the tree, starting at the root, until the required node is found. If the node is not found, a null is returned.

Parameters:

fqn - Fqn of the node to find

includeDeletedNodes - if true, deleted nodes are also considered

includeInvalidNodes - if true, invalid nodes are also considered

Returns:

the node, if found, or null otherwise.

exists

public boolean exists(Fqn fqn)

Tests if an Fqn exists and is valid and not deleted.

Parameters:

fqn - the fqn representing the node to test

Returns:

true if the node exists, false otherwise.

hasChildren

public boolean hasChildren(Fqn fqn)

Returns true if the Fqn exists, is valid and is not deleted, and the node has children.

Parameters:

fqn - the fqn to test

Returns:

true if the Fqn exists, is valid and is not deleted, and the node has children.

buildNodeData

public List<NodeData> buildNodeData(List<NodeData> list,
                                    NodeSPI node)

Prepares a list of NodeData objects for a specified node and all its children.

Parameters:

list - List of NodeData objects, which will be added to.

node - node to recursively add to the list

Returns:

the same list passed in

getNodesForEviction

public List<Fqn> getNodesForEviction(Fqn fqn,
                                     boolean recursive)

Generates a list of nodes for eviction. This filters out nodes that cannot be evicted, such as those which are marked as resident. See Node.setResident(boolean).

Parameters:

fqn - the node to consider for eviction

recursive - if recursive, child nodes are also considered

Returns:

a list of Fqns that can be considered for eviction

toString

public String toString()

Overrides:

toString in class Object

getInternalFqns

public Set<Fqn> getInternalFqns()

Returns a Set of Fqns of the topmost node of internal regions that should not included in standard state transfers. Will include BuddyManager.BUDDY_BACKUP_SUBTREE if buddy replication is enabled.

Returns:

an unmodifiable Set. Will not return null.

toString

public String toString(boolean details)

Returns a debug string with optional details of contents.

getNumberOfLocksHeld

public int getNumberOfLocksHeld()

Returns the number of read or write locks held across the entire cache.

getNumberOfNodes

public int getNumberOfNodes()

Returns an approximation of the total number of nodes in the cache. Since this method doesn't acquire any locks, the number might be incorrect, or the method might even throw a ConcurrentModificationException

printDetails

public String printDetails()

Prints information about the contents of the nodes in the cache's current in-memory state. Does not load any previously evicted nodes from a cache loader, so evicted nodes will not be included.

printLockInfo

public String printLockInfo()

Returns lock information.

getNumberOfAttributes

public int getNumberOfAttributes(Fqn fqn)

Returns an approximation of the total number of attributes in this sub cache.

See Also:

getNumberOfAttributes(org.jboss.cache.Fqn)

getNumberOfAttributes

public int getNumberOfAttributes()

Returns an approximation of the total number of attributes in the cache. Since this method doesn't acquire any locks, the number might be incorrect, or the method might even throw a ConcurrentModificationException

removeFromDataStructure

public boolean removeFromDataStructure(Fqn f,
                                       boolean skipMarkerCheck)

Removes the actual node from the tree data structure.

Parameters:

f - the Fqn of the node to remove

skipMarkerCheck - if true, skips checking the boolean NodeSPI.isDeleted() flag and deletes the node anyway.

Returns:

Returns true if the node was found and removed, false if not.

evict

public void evict(Fqn fqn,
                  boolean recursive)

evict

public boolean evict(Fqn fqn)

Returns:

true if the FQN is leaf and was removed; false if is an intermediate FQN and only contained data is droped.

removeData

protected void removeData(Fqn fqn)

createNodes

public Object[] createNodes(Fqn fqn)

Traverses the tree to the given Fqn, creating nodes if needed. Returns a list of nodes created, as well as a reference to the last node.

E.g., Object[] results = createNode(myFqn); results[0] // this is a List<NodeSPI> of nodes created in getting to the target node. results[1] // is a NodeSPI reference to the target node, regardless of whether it was created or just found.

Parameters:

fqn - fqn to find

Returns:

see above.

createNodesLocally

public void createNodesLocally(Fqn<?> fqn,
                               Map<?,?> data)
                        throws CacheException

Throws:

CacheException