viper.api.impl
Class EventfulNodeHelper

java.lang.Object
  viper.api.impl.EventfulNodeHelper

All Implemented Interfaces:

EventfulNode, Node, TransactionalNode

Direct Known Subclasses:

AttrConfigImpl, AttributeImpl, ConfigImpl, DescriptorImpl, SourcefileImpl, ViperDataImpl

public abstract class EventfulNodeHelper

extends java.lang.Object

implements TransactionalNode

An abstract viper node class.

Author:

davidm

Nested Class Summary

Nested classes inherited from class viper.api.extensions.TransactionalNode

TransactionalNode.Transaction

Field Summary

protected java.lang.String	childNodeType
protected boolean	notifyingListeners

Constructor Summary

EventfulNodeHelper()

Method Summary

void	addChild(Node n) (Optional) Adds a child in some arbitrary position.
void	addChild(Node n, boolean undoable) Adds a child node, but returns an undoable or non-undoable event according to the parameter.
void	addNodeListener(NodeListener nl) Adds a listener for changes to the node or its children.
TransactionalNode.Transaction	begin(java.lang.String uri) Starts a transaction on this node.
void	fireMajorNodeChanged(MajorNodeChangeEvent mnce) Fires the given major node change event, combining several other changes into one.
void	fireMinorNodeChanged(MinorNodeChangeEvent mnce) Fires the given minor node change event, indicating that some aspect of the node has changed.
void	fireNodeChanged(NodeChangeEvent nce) Fires the given node change event, indicating that some of the children of the node have been added or removed.
protected abstract java.util.logging.Logger	getLogger()
ViperData	getRoot() Gets the root of the tree.
boolean	hasListeners() Tests to see if any listeners are attached to the current node.
protected abstract void	helpSetChild(int i, Node n, TransactionalNode.Transaction t, boolean insert) Replace the child at index i with the given node.
boolean	isNotifyingListeners()
boolean	isWriteLocked() Tests to see if set will work.
protected abstract void	postHelpSetChild(int i, Node n, TransactionalNode.Transaction t, boolean insert) Invoked after the event has been generated for the corresponding helpSetChild call.
void	removeChild(int i) (Optional) Remove child at offset i.
void	removeChild(int i, boolean undoable) Removes the specified child, emitting an undoable or non-undoable version of the event as requested.
void	removeChild(Node n) (Optional) Remove child n.
void	removeNodeListener(NodeListener nl) Adds a listener for changes to the node or its children.
void	setChild(int i, Node n) (Optional) Sets the child at i to n.

Methods inherited from class java.lang.Object

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

Methods inherited from interface viper.api.Node

getChild, getChildren, getNumberOfChildren, getParent, hasChild, indexOf

Field Detail

childNodeType

protected java.lang.String childNodeType

notifyingListeners

protected boolean notifyingListeners

Constructor Detail

EventfulNodeHelper

public EventfulNodeHelper()

Method Detail

hasListeners

public boolean hasListeners()

Tests to see if any listeners are attached to the current node.

Returns:

false when no listeners are attached

addNodeListener

public void addNodeListener(NodeListener nl)

Description copied from interface: EventfulNode

Adds a listener for changes to the node or its children.

Specified by:

addNodeListener in interface EventfulNode

Parameters:

nl - the node listener to add

See Also:

EventfulNode.addNodeListener(viper.api.extensions.NodeListener)

removeNodeListener

public void removeNodeListener(NodeListener nl)

Description copied from interface: EventfulNode

Adds a listener for changes to the node or its children.

Specified by:

removeNodeListener in interface EventfulNode

Parameters:

nl - the node listener to add

See Also:

EventfulNode.removeNodeListener(viper.api.extensions.NodeListener)

getRoot

public ViperData getRoot()

Description copied from interface: Node

Gets the root of the tree.

Specified by:

getRoot in interface Node

Returns:

the node at the root of the tree.

See Also:

Node.getRoot()

getLogger

protected abstract java.util.logging.Logger getLogger()

fireNodeChanged

public void fireNodeChanged(NodeChangeEvent nce)

Description copied from interface: EventfulNode

Fires the given node change event, indicating that some of the children of the node have been added or removed. This probably shouldn't be part of the interface, but instead on an Abstract type.

Specified by:

fireNodeChanged in interface EventfulNode

Parameters:

nce - the change event

See Also:

EventfulNode.fireNodeChanged(viper.api.extensions.NodeChangeEvent)

isWriteLocked

public boolean isWriteLocked()

Tests to see if set will work.

Returns:

fireMinorNodeChanged

public void fireMinorNodeChanged(MinorNodeChangeEvent mnce)

Description copied from interface: EventfulNode

Fires the given minor node change event, indicating that some aspect of the node has changed. This probably shouldn't be part of the interface, but instead on an Abstract type.

Specified by:

fireMinorNodeChanged in interface EventfulNode

Parameters:

mnce - the change event

See Also:

EventfulNode.fireMinorNodeChanged(viper.api.extensions.MinorNodeChangeEvent)

fireMajorNodeChanged

public void fireMajorNodeChanged(MajorNodeChangeEvent mnce)

Description copied from interface: EventfulNode

Fires the given major node change event, combining several other changes into one. This probably shouldn't be part of the interface, but instead on an Abstract type.

Specified by:

fireMajorNodeChanged in interface EventfulNode

Parameters:

mnce - the change event

See Also:

EventfulNode.fireMajorNodeChanged(viper.api.extensions.MajorNodeChangeEvent)

helpSetChild

protected abstract void helpSetChild(int i,
                                     Node n,
                                     TransactionalNode.Transaction t,
                                     boolean insert)

Replace the child at index i with the given node. If insert is set, makes the child at index i the given node and shifts i to i+1, i+1 to i+2, and so on. This should not generate an event.

Parameters:

i - the index to insert/set

n - the node to insert

t - the transaction associated with the event, if it exists. Otherwise, it is null.

insert - true if the node should be inserted, false if the current node i should be replaced

postHelpSetChild

protected abstract void postHelpSetChild(int i,
                                         Node n,
                                         TransactionalNode.Transaction t,
                                         boolean insert)

Invoked after the event has been generated for the corresponding helpSetChild call. This is useful if you need to order your events. This should not generate an event.

Parameters:

i - the index to insert/set

n - the node to insert

t - the transaction associated with the event, if it exists. Otherwise, it is null.

insert - true if the node should be inserted, false if the current node i should be replaced

addChild

public void addChild(Node n)

Description copied from interface: Node

(Optional) Adds a child in some arbitrary position.

Specified by:

addChild in interface Node

Parameters:

n - the node to add

See Also:

Node.addChild(viper.api.Node)

setChild

public void setChild(int i,
                     Node n)

Description copied from interface: Node

(Optional) Sets the child at i to n.

Specified by:

setChild in interface Node

Parameters:

i - the index of the child to replace

n - the new value of the child

See Also:

Node.setChild(int, viper.api.Node)

removeChild

public void removeChild(int i)

Description copied from interface: Node

(Optional) Remove child at offset i.

Specified by:

removeChild in interface Node

Parameters:

i - child to remove

See Also:

Node.removeChild(int)

removeChild

public void removeChild(Node n)

Description copied from interface: Node

(Optional) Remove child n.

Specified by:

removeChild in interface Node

Parameters:

n - child to remove.

See Also:

Node.removeChild(viper.api.Node)

addChild

public void addChild(Node n,
                     boolean undoable)

Adds a child node, but returns an undoable or non-undoable event according to the parameter.

Parameters:

n - the node to add

undoable - whether to allow undo

See Also:

Node.addChild(viper.api.Node)

removeChild

public void removeChild(int i,
                        boolean undoable)

Removes the specified child, emitting an undoable or non-undoable version of the event as requested.

Parameters:

i - the index of the child to remove

undoable - whether to allow undoing the event

begin

public TransactionalNode.Transaction begin(java.lang.String uri)

Description copied from interface: TransactionalNode

Starts a transaction on this node.

Specified by:

begin in interface TransactionalNode

Parameters:

uri - an identifier to associate with the transaction; useful for logging

Returns:

the Transaction object associated with the new transaction.

See Also:

TransactionalNode.begin(java.lang.String)

isNotifyingListeners

public boolean isNotifyingListeners()

Specified by:

isNotifyingListeners in interface EventfulNode

Returns: