org.apache.jackrabbit.core.state
Class ItemState

java.lang.Object
  org.apache.jackrabbit.core.state.ItemState

Direct Known Subclasses:

NodeState, PropertyState

public abstract class ItemState
extends Object

ItemState represents the state of an Item.

Field Summary

protected ItemState	overlayedState the backing persistent item state (may be null)
protected int	status the internal status of this item state
static int	STATUS_EXISTING 'existing', i.e. persistent state
static int	STATUS_EXISTING_MODIFIED 'existing', i.e. persistent state that has been transiently modified (copy-on-write)
static int	STATUS_EXISTING_REMOVED 'existing', i.e. persistent state that has been transiently removed (copy-on-write)
static int	STATUS_NEW 'new' state
static int	STATUS_STALE_DESTROYED 'existing', i.e. persistent state that has been destroyed by somebody else
static int	STATUS_UNDEFINED the status is undefined

Constructor Summary

protected	ItemState(int initialStatus, boolean isTransient) Constructs a new unconnected item state
protected	ItemState(ItemState overlayedState, int initialStatus, boolean isTransient) Constructs a new item state that is initially connected to an overlayed state.

Method Summary

abstract long	calculateMemoryFootprint() Returns the approximate memory consumption of this state.
protected void	connect(ItemState overlayedState) Connect this state to some underlying overlayed state.
abstract void	copy(ItemState state, boolean syncModCount) Copy state information from another state into this state
void	discard() Discards this instance, i.e. renders it 'invalid'.
protected void	disconnect() Disconnect this state from the underlying overlayed state.
ItemStateListener	getContainer() Return the parent container that will receive notifications about changes to this state.
abstract ItemId	getId() Returns the identifier of this item.
short	getModCount() Returns the modification count.
ItemState	getOverlayedState() Returns the persistent state backing this transient state or null if there is no persistent state (i.e..
abstract NodeId	getParentId() Returns the NodeId of the parent NodeState or null if either this item state represents the root node or this item state is 'free floating', i.e. not attached to the repository's hierarchy.
int	getStatus() Returns the status of this item.
boolean	hasOverlayedState() Determines if this item state is overlying persistent state.
protected boolean	isConnected() Return a flag indicating whether this state is connected to some other state.
abstract boolean	isNode() Determines if this item state represents a node.
boolean	isStale() Determines whether this item state has become stale.
boolean	isTransient() Returns true if this item state represents new or modified state (i.e. the result of copy-on-write) or false if it represents existing, unmodified state.
protected void	notifyStateCreated() Notify the parent container about changes to this state.
protected void	notifyStateDestroyed() Notify the parent container about changes to this state.
protected void	notifyStateDiscarded() Notify the parent container about changes to this state.
void	notifyStateUpdated() Notify the parent container about changes to this state.
protected void	reconnect() Reconnect this state to the overlayed state that it has been disconnected from earlier.
void	setContainer(ItemStateListener container) Set the parent container that will receive notifications about changes to this state.
void	setModCount(short modCount) Sets the modification count.
void	setStatus(int newStatus) Sets the new status of this item.

Methods inherited from class java.lang.Object

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

Field Detail

STATUS_UNDEFINED

public static final int STATUS_UNDEFINED

the status is undefined

See Also:

Constant Field Values

STATUS_EXISTING

public static final int STATUS_EXISTING

'existing', i.e. persistent state

See Also:

Constant Field Values

STATUS_EXISTING_MODIFIED

public static final int STATUS_EXISTING_MODIFIED

'existing', i.e. persistent state that has been transiently modified (copy-on-write)

See Also:

Constant Field Values

STATUS_EXISTING_REMOVED

public static final int STATUS_EXISTING_REMOVED

'existing', i.e. persistent state that has been transiently removed (copy-on-write)

See Also:

Constant Field Values

STATUS_NEW

public static final int STATUS_NEW

'new' state

See Also:

Constant Field Values

STATUS_STALE_DESTROYED

public static final int STATUS_STALE_DESTROYED

'existing', i.e. persistent state that has been destroyed by somebody else

See Also:

Constant Field Values

status

protected int status

the internal status of this item state

overlayedState

protected ItemState overlayedState

the backing persistent item state (may be null)

Constructor Detail

ItemState

protected ItemState(int initialStatus,
                    boolean isTransient)

Constructs a new unconnected item state

Parameters:

initialStatus - the initial status of the item state object

isTransient - flag indicating whether this state is transient or not

ItemState

protected ItemState(ItemState overlayedState,
                    int initialStatus,
                    boolean isTransient)

Constructs a new item state that is initially connected to an overlayed state.

Parameters:

overlayedState - the backing item state being overlayed

initialStatus - the initial status of the new ItemState instance

isTransient - flag indicating whether this state is transient or not

Method Detail

copy

public abstract void copy(ItemState state,
                          boolean syncModCount)

Copy state information from another state into this state

Parameters:

state - source state information

syncModCount - if the modCount should be synchronized.

connect

protected void connect(ItemState overlayedState)

Connect this state to some underlying overlayed state.

reconnect

protected void reconnect()

Reconnect this state to the overlayed state that it has been disconnected from earlier.

disconnect

protected void disconnect()

Disconnect this state from the underlying overlayed state.

isConnected

protected boolean isConnected()

Return a flag indicating whether this state is connected to some other state.

Returns:

true if this state is connected, false otherwise.

notifyStateDiscarded

protected void notifyStateDiscarded()

Notify the parent container about changes to this state.

notifyStateCreated

protected void notifyStateCreated()

Notify the parent container about changes to this state.

notifyStateUpdated

public void notifyStateUpdated()

Notify the parent container about changes to this state.

notifyStateDestroyed

protected void notifyStateDestroyed()

Notify the parent container about changes to this state.

isNode

public abstract boolean isNode()

Determines if this item state represents a node.

Returns:

true if this item state represents a node, otherwise false.

getId

public abstract ItemId getId()

Returns the identifier of this item.

Returns:

the id of this item.

isTransient

public boolean isTransient()

Returns true if this item state represents new or modified state (i.e. the result of copy-on-write) or false if it represents existing, unmodified state.

Returns:

true if this item state is modified or new, otherwise false

isStale

public boolean isStale()

Determines whether this item state has become stale.

Returns:

true if this item state has become stale, false otherwise.

getParentId

public abstract NodeId getParentId()

Returns the NodeId of the parent NodeState or null if either this item state represents the root node or this item state is 'free floating', i.e. not attached to the repository's hierarchy.

Returns:

the parent NodeState's Id

getStatus

public int getStatus()

Returns the status of this item.

Returns:

the status of this item.

setStatus

public void setStatus(int newStatus)

Sets the new status of this item.

Parameters:

newStatus - the new status

getModCount

public short getModCount()

Returns the modification count.

Returns:

the modification count.

setModCount

public void setModCount(short modCount)

Sets the modification count.

Parameters:

modCount - the modification count of this item

discard

public void discard()

Discards this instance, i.e. renders it 'invalid'.

hasOverlayedState

public boolean hasOverlayedState()

Determines if this item state is overlying persistent state.

Returns:

true if this item state is overlying persistent state, otherwise false.

getOverlayedState

public ItemState getOverlayedState()

Returns the persistent state backing this transient state or null if there is no persistent state (i.e.. this state is purely transient).

Returns:

the persistent item state or null if there is no persistent state.

setContainer

public void setContainer(ItemStateListener container)

Set the parent container that will receive notifications about changes to this state.

Parameters:

container - container to be informed on modifications

getContainer

public ItemStateListener getContainer()

Return the parent container that will receive notifications about changes to this state. Returns null if none has been yet assigned.

Returns:

container or null

calculateMemoryFootprint

public abstract long calculateMemoryFootprint()

Returns the approximate memory consumption of this state.

Returns:

the approximate memory consumption of this state.