org.apache.jackrabbit.core.version
Class VersionManagerImpl

java.lang.Object
  org.apache.jackrabbit.core.version.VersionManagerImpl

All Implemented Interfaces:

UpdateEventListener, ItemStateListener, VersionManager

public class VersionManagerImpl
extends Object
implements ItemStateListener, UpdateEventListener

This Class implements a VersionManager.

Nested Class Summary

static class

VersionManagerImpl.DynamicESCFactory

Field Summary

protected NodeStateEx	historyRoot Persistent root node of the version histories.
protected NodeTypeRegistry	ntReg Node type registry.
protected LocalItemStateManager	stateMgr State manager for the version storage.

Constructor Summary

VersionManagerImpl(PersistenceManager pMgr, FileSystem fs, NodeTypeRegistry ntReg, DelegatingObservationDispatcher obsMgr, NodeId rootId, NodeId rootParentId, ItemStateCacheFactory cacheFactory, ISMLocking ismLocking)
Creates a new version manager

Method Summary

protected void	acquireReadLock() aquires the read lock on this version manager.
protected void	acquireWriteLock() aquires the write lock on this version manager.
protected String	calculateCheckinVersionName(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history, NodeImpl node) Calculates the name of the new version that will be created by a checkin call.
protected InternalVersion	checkin(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history, NodeImpl node) Checks in a node
Version	checkin(NodeImpl node) invokes the checkin() on the persistent version manager and remaps the newly created version objects.
void	close() Close this version manager.
protected InternalVersionItem	createInternalVersionItem(NodeId id) Creates an InternalVersionItem based on the NodeState identified by id.
protected VersionItemStateManager	createItemStateManager(PersistenceManager pMgr, NodeId rootId, NodeTypeRegistry ntReg, ItemStateCacheFactory cacheFactory, ISMLocking ismLocking) Creates a VersionItemStateManager or derivative.
protected VersionHistoryInfo	createVersionHistory(Session session, NodeState node) Creates a new version history.
void	externalUpdate(ChangeLog changes, List events) Handle an external update.
VersionManagerImpl.DynamicESCFactory	getEscFactory() Returns the event state collection factory.
protected InternalVersionItem	getItem(NodeId id) Returns the item with the given persistent id.
PersistenceManager	getPersistenceManager() Return the persistence manager.
protected SharedItemStateManager	getSharedStateMgr() Return the shared item state manager.
InternalVersion	getVersion(NodeId id) Returns the version with the given id
InternalVersionHistory	getVersionHistory(NodeId id) Returns the version history with the given id
VersionHistoryInfo	getVersionHistory(Session session, NodeState node) Returns information about the version history of the specified node.
VirtualItemStateProvider	getVirtualItemStateProvider() returns the virtual item state provider that exposes the internal versions as items.
boolean	hasItem(NodeId id) Return a flag indicating if the item specified exists.
protected boolean	hasItemReferences(InternalVersionItem item) Checks if there are item references (from outside the version storage) that reference the given version item.
protected void	itemDiscarded(InternalVersionItem item) Invoked by the internal version item itself, when it's underlying persistence state was discarded.
void	itemsUpdated(Collection items) Invoked by some external source to indicate that some items in the versions tree were updated.
protected void	releaseReadLock() releases the read lock on this version manager.
protected void	releaseWriteLock() releases the write lock on this version manager.
protected void	removeVersion(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history, Name name) Removes the specified version from the history
void	removeVersion(VersionHistory history, Name name) Removes the specified version from the given version history.
void	setEventChannel(UpdateEventChannel eventChannel) Set an event channel to inform about updates.
protected InternalVersion	setVersionLabel(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history, Name version, Name label, boolean move) Set version label on the specified version.
Version	setVersionLabel(VersionHistory history, Name version, Name label, boolean move) Sets the version label to the given version.
void	stateCreated(ItemState created) Called when an ItemState has successfully been created (i.e. its underlying persistent state was created).
void	stateDestroyed(ItemState destroyed) Called when an ItemState has successfully been removed (i.e. its underlying persistent state has been destroyed).
void	stateDiscarded(ItemState discarded) Called when an ItemState has been discarded (i.e. it has been rendered 'invalid').
void	stateModified(ItemState modified) Called when an ItemState has successfully been modified (i.e. its underlying persistent state has changed).
protected void	versionCreated(InternalVersion version) Invoked when a new internal item has been created.
protected void	versionDestroyed(InternalVersion version) Invoked when a new internal item has been destroyed.

Methods inherited from class java.lang.Object

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

Field Detail

stateMgr

protected LocalItemStateManager stateMgr

State manager for the version storage.

ntReg

protected final NodeTypeRegistry ntReg

Node type registry.

historyRoot

protected NodeStateEx historyRoot

Persistent root node of the version histories.

Constructor Detail

VersionManagerImpl

public VersionManagerImpl(PersistenceManager pMgr,
                          FileSystem fs,
                          NodeTypeRegistry ntReg,
                          DelegatingObservationDispatcher obsMgr,
                          NodeId rootId,
                          NodeId rootParentId,
                          ItemStateCacheFactory cacheFactory,
                          ISMLocking ismLocking)
                   throws RepositoryException

Creates a new version manager

Throws:

RepositoryException

Method Detail

getVirtualItemStateProvider

public VirtualItemStateProvider getVirtualItemStateProvider()

returns the virtual item state provider that exposes the internal versions as items.

Specified by:

getVirtualItemStateProvider in interface VersionManager

Returns:

the virtual item state provider.

getPersistenceManager

public PersistenceManager getPersistenceManager()

Return the persistence manager.

Returns:

the persistence manager

close

public void close()
           throws Exception

Close this version manager. After having closed a persistence manager, further operations on this object are treated as illegal and throw

Specified by:

close in interface VersionManager

Throws:

Exception - if an error occurs

getEscFactory

public VersionManagerImpl.DynamicESCFactory getEscFactory()

Returns the event state collection factory.

Returns:

the event state collection factory.

createVersionHistory

protected VersionHistoryInfo createVersionHistory(Session session,
                                                  NodeState node)
                                           throws RepositoryException

Creates a new version history. This action is needed either when creating a new 'mix:versionable' node or when adding the 'mix:versionable' mixin to a node.

This method must not be synchronized since it could cause deadlocks with item-reading listeners in the observation thread.

Returns:

identifier of the new version history node

Throws:

RepositoryException

See Also:

getVersionHistory(Session, NodeState)

hasItem

public boolean hasItem(NodeId id)

Return a flag indicating if the item specified exists. Subclass responsibility.

Parameters:

id - the id of the item

Returns:

true if the item exists; false otherwise

getItem

protected InternalVersionItem getItem(NodeId id)
                               throws RepositoryException

Returns the item with the given persistent id. Subclass responsibility.

Please note, that the overridden method must aquire the readlock before reading the state manager.

Parameters:

id - the id of the item

Returns:

version item

Throws:

RepositoryException - if an error occurs

checkin

public Version checkin(NodeImpl node)
                throws RepositoryException

invokes the checkin() on the persistent version manager and remaps the newly created version objects.

This method must not be synchronized since it could cause deadlocks with item-reading listeners in the observation thread.

Specified by:

checkin in interface VersionManager

Returns:

Throws:

RepositoryException

removeVersion

public void removeVersion(VersionHistory history,
                          Name name)
                   throws VersionException,
                          RepositoryException

Removes the specified version from the given version history.

This method must not be synchronized since it could cause deadlocks with item-reading listeners in the observation thread.

Specified by:

removeVersion in interface VersionManager

Throws:

RepositoryException

VersionException

setVersionLabel

public Version setVersionLabel(VersionHistory history,
                               Name version,
                               Name label,
                               boolean move)
                        throws RepositoryException

Sets the version label to the given version. If the label is already assigned to another version, a VersionException is thrown unless move is true. If version is null, the label is removed from the respective version. In either case, the version the label was previously assigned is returned, or null of the label was not moved.

This method must not be synchronized since it could cause deadlocks with item-reading listeners in the observation thread.

Specified by:

setVersionLabel in interface VersionManager

Returns:

Throws:

RepositoryException

itemsUpdated

public void itemsUpdated(Collection items)

Invoked by some external source to indicate that some items in the versions tree were updated. Version histories are reloaded if possible. Matching items are removed from the cache.

Parameters:

items - items updated

setEventChannel

public void setEventChannel(UpdateEventChannel eventChannel)

Set an event channel to inform about updates.

Parameters:

eventChannel - event channel

itemDiscarded

protected void itemDiscarded(InternalVersionItem item)

Invoked by the internal version item itself, when it's underlying persistence state was discarded.

hasItemReferences

protected boolean hasItemReferences(InternalVersionItem item)
                             throws RepositoryException

Checks if there are item references (from outside the version storage) that reference the given version item. Subclass responsiblity.

Please note, that the overridden method must aquire the readlock before reading the state manager.

Parameters:

item - version item

Returns:

true if there are item references from outside the version storage; false otherwise.

Throws:

RepositoryException - if an error occurs while reading from the repository.

getSharedStateMgr

protected SharedItemStateManager getSharedStateMgr()

Return the shared item state manager.

createItemStateManager

protected VersionItemStateManager createItemStateManager(PersistenceManager pMgr,
                                                         NodeId rootId,
                                                         NodeTypeRegistry ntReg,
                                                         ItemStateCacheFactory cacheFactory,
                                                         ISMLocking ismLocking)
                                                  throws ItemStateException

Creates a VersionItemStateManager or derivative.

Parameters:

pMgr - persistence manager

rootId - root node id

ntReg - node type registry

cacheFactory - cache factory

ismLocking - the ISM locking implementation

Returns:

item state manager

Throws:

ItemStateException - if an error occurs

stateCreated

public void stateCreated(ItemState created)

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

Not used.

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).

Not used.

Specified by:

stateModified in interface ItemStateListener

Parameters:

modified - the ItemState that has been 'modified'

stateDestroyed

public void stateDestroyed(ItemState destroyed)

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

Remove item from cache on removal.

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').

Not used.

Specified by:

stateDiscarded in interface ItemStateListener

Parameters:

discarded - the ItemState that has been discarded

See Also:

ItemState.discard()

externalUpdate

public void externalUpdate(ChangeLog changes,
                           List events)
                    throws RepositoryException

Handle an external update.

Specified by:

externalUpdate in interface UpdateEventListener

Parameters:

changes - external changes containing only node and property ids.

events - events to deliver

Throws:

RepositoryException - if the update cannot be processed

getVersion

public InternalVersion getVersion(NodeId id)
                           throws RepositoryException

Returns the version with the given id

Specified by:

getVersion in interface VersionManager

Returns:

the version.

Throws:

RepositoryException

getVersionHistory

public InternalVersionHistory getVersionHistory(NodeId id)
                                         throws RepositoryException

Returns the version history with the given id

Specified by:

getVersionHistory in interface VersionManager

Returns:

the version history.

Throws:

RepositoryException

acquireWriteLock

protected void acquireWriteLock()

aquires the write lock on this version manager.

releaseWriteLock

protected void releaseWriteLock()

releases the write lock on this version manager.

acquireReadLock

protected void acquireReadLock()

aquires the read lock on this version manager.

releaseReadLock

protected void releaseReadLock()

releases the read lock on this version manager.

getVersionHistory

public VersionHistoryInfo getVersionHistory(Session session,
                                            NodeState node)
                                     throws RepositoryException

Returns information about the version history of the specified node. If the given node does not already have an associated version history, then an empty history is automatically created. This method should only be called by code that already knows that the specified node is versionable.

Specified by:

getVersionHistory in interface VersionManager

node - node whose version history should be returned

Returns:

identifiers of the version history and root version nodes

Throws:

RepositoryException - if an error occurs

checkin

protected InternalVersion checkin(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history,
                                  NodeImpl node)
                           throws RepositoryException

Checks in a node

Parameters:

history - the version history

node - node to checkin

Returns:

internal version

Throws:

RepositoryException - if an error occurs

See Also:

Node.checkin()

calculateCheckinVersionName

protected String calculateCheckinVersionName(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history,
                                             NodeImpl node)
                                      throws RepositoryException

Calculates the name of the new version that will be created by a checkin call. The name is determined as follows:

• first the predecessor version with the shortes name is searched.
• if that predecessor version is the root version, the new version gets the name "{number of successors}+1" + ".0"
• if that predecessor version has no successor, the last digit of it's version number is incremented.
• if that predecessor version has successors but the incremented name does not exist, that name is used.
• otherwise a ".0" is added to the name until a non conflicting name is found.
  Example Graph: jcr:rootVersion | | 1.0 2.0 | 1.1 | 1.2 ---\ ------\ | \ \ 1.3 1.2.0 1.2.0.0 | | 1.4 1.2.1 ----\ | | \ 1.5 1.2.2 1.2.1.0 | | | 1.6 | 1.2.1.1 |-----/ 1.7

  Parameters:

  history - the version history

  node - the node to checkin

  Returns:

  the new version name

  Throws:

  RepositoryException - if an error occurs.

removeVersion

protected void removeVersion(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history,
                             Name name)
                      throws VersionException,
                             RepositoryException

Removes the specified version from the history

Parameters:

history - the version history from where to remove the version.

name - the name of the version to remove.

Throws:

VersionException - if the version history does not have a version with name.

RepositoryException - if any other error occurs.

setVersionLabel

protected InternalVersion setVersionLabel(org.apache.jackrabbit.core.version.InternalVersionHistoryImpl history,
                                          Name version,
                                          Name label,
                                          boolean move)
                                   throws RepositoryException

Set version label on the specified version.

Parameters:

history - version history

version - version name

label - version label

move - true to move from existing version; false otherwise

Throws:

RepositoryException - if an error occurs

versionCreated

protected void versionCreated(InternalVersion version)

Invoked when a new internal item has been created.

Parameters:

version - internal version item

versionDestroyed

protected void versionDestroyed(InternalVersion version)

Invoked when a new internal item has been destroyed.

Parameters:

version - internal version item

createInternalVersionItem

protected InternalVersionItem createInternalVersionItem(NodeId id)
                                                 throws RepositoryException

Creates an InternalVersionItem based on the NodeState identified by id.

Parameters:

id - the node id of the version item.

Returns:

the version item or null if there is no node state with the given id.

Throws:

RepositoryException - if an error occurs while reading from the version storage.