org.eclipse.persistence.jpa.jpql.tools.model.query

Class ChangeSupport

java.lang.Object

org.eclipse.persistence.jpa.jpql.tools.model.query.ChangeSupport

public class ChangeSupport
extends java.lang.Object

This ChangeSupport is responsible to notifies registered listeners upon changes made to a StateObject, those changes are either a property has changed (IPropertyChangeListener) or the content of a list has changed (IListChangeListener).

Version:

2.4

Author:

Pascal Filion

Since:

2.4

Constructor Summary

Constructors

Constructor and Description
ChangeSupport(StateObject source) Creates a new ChangeSupport.

Method Summary

Modifier and Type	Method and Description
<T> void	addItem(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, T item) Adds the given item as a child to the given list.
<T> void	addItems(ListHolderStateObject<T> source, java.util.List<T> list, java.lang.String listName, java.util.List<? extends T> items) Adds the given items as children to the given list.
void	addListChangeListener(java.lang.String listName, IListChangeListener<?> listener) Registers the given IListChangeListener for the specified list.
protected <T> void	addListener(java.util.Map<java.lang.String,java.util.List<T>> listeners, java.lang.Class<?> listenerType, java.lang.String name, T listener) Registers the given list for the specified name.
void	addPropertyChangeListener(java.lang.String propertyName, IPropertyChangeListener<?> listener) Registers the given IPropertyChangeListener for the specified property.
<T> boolean	canMoveDown(java.util.List<T> list, T stateObject) Determines whether the given item can be moved down by one position in the list owned by its parent.
<T> boolean	canMoveUp(java.util.List<T> list, T item) Determines whether the given item can be moved up by one position in the list owned by its parent.
protected <T> void	fireListChangeEvent(IListChangeEvent<T> event)
void	firePropertyChanged(java.lang.String propertyName, java.lang.Object oldValue, java.lang.Object newValue) Notifies the IPropertyChangeListeners that have been registered with the given property name that the property has changed.
boolean	hasListChangeListeners(java.lang.String listName) Determines whether there are at least one IListChangeListener registered to listen for changes made to the list with the given list name.
protected boolean	hasListeners(java.util.Map<java.lang.String,?> listeners, java.lang.String name) Determines whether there are at least one listener registered.
boolean	hasPropertyChangeListeners(java.lang.String propertyName) Determines whether there are at least one IPropertyChangeListener registered to listen for changes made to the property with the given property name.
protected void	initialize(StateObject source) Initializes this ChangeSupport.
protected <T> ListIterable<IListChangeListener<T>>	listChangeListeners(java.lang.String listName)
<T> void	moveDown(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, T item) Moves the given StateObject down by one position in the list owned by its parent.
protected <T> void	moveItem(ListHolderStateObject<T> source, java.util.List<T> items, IListChangeEvent.EventType eventType, java.lang.String listName, T item, int oldIndex, int newIndex) Moves the given item from its current position to a new position in the list owned by its parent.
<T> void	moveUp(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, T item) Moves the given item up by one position in the list owned by its parent.
protected ListIterable<IPropertyChangeListener<?>>	propertyChangeListeners(java.lang.String propertyName)
<T> void	removeItem(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, T item) Removes the given item from the list of children.
<T> void	removeItems(ListHolderStateObject<T> source, java.util.List<? extends T> list, java.lang.String listName, java.util.Collection<? extends T> items) Removes the given items from the list of children.
void	removeListChangeListener(java.lang.String listName, IListChangeListener<?> listener) Unregisters the given IListChangeListener that was registered for the specified list.
protected <T> void	removeListener(java.util.Map<java.lang.String,java.util.List<T>> listeners, java.lang.Class<?> listenerType, java.lang.String name, T listener) Unregisters the given listener that was registered for the specified name.
void	removePropertyChangeListener(java.lang.String propertyName, IPropertyChangeListener<?> listener) Unregisters the given IPropertyChangeListener that was registered for the specified property.
<T> void	replaceItem(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, int index, T item) Replaces the item at the given position by a new one.
<T> void	replaceItems(ListHolderStateObject<T> source, java.util.List<T> items, java.lang.String listName, java.util.List<T> newItems) Replaces the given list by removing any existing items and adding the items contained in the second list.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChangeSupport

public ChangeSupport(StateObject source)

Creates a new ChangeSupport.

Parameters:

source - The object for which this object will take care of notifying the listeners upon changes made to the object's internal state

Throws:

java.lang.NullPointerException - The source StateObject cannot be null

Method Detail

addItem

public <T> void addItem(ListHolderStateObject<T> source,
                        java.util.List<T> items,
                        java.lang.String listName,
                        T item)

Adds the given item as a child to the given list.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of to which the child is added

listName - The name associated with the list

item - The child to become a child of this one

addItems

public <T> void addItems(ListHolderStateObject<T> source,
                         java.util.List<T> list,
                         java.lang.String listName,
                         java.util.List<? extends T> items)

Adds the given items as children to the given list.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

list - The list of items to which the child is added

listName - The name associated with the list

items - The child to become children of this one

addListChangeListener

public void addListChangeListener(java.lang.String listName,
                                  IListChangeListener<?> listener)

Registers the given IListChangeListener for the specified list. The listener will be notified only when items are added, removed, moved from the list.

Parameters:

listName - The name of the list for which the listener will be notified when the content of the list has changed

listener - The listener to be notified upon changes

Throws:

java.lang.NullPointerException - IListChangeListener cannot be null

java.lang.IllegalArgumentException - The listener is already registered with the list name

addListener

protected <T> void addListener(java.util.Map<java.lang.String,java.util.List<T>> listeners,
                               java.lang.Class<?> listenerType,
                               java.lang.String name,
                               T listener)

Registers the given list for the specified name. The listener will be notified upon changes.

Parameters:

listeners - The list of listeners from which the given listener is added

listenerType - The type of the listener, which is only used in the exception's message

name - The name of the event for which the listener is registered

listener - The listener to register

Throws:

java.lang.NullPointerException - IPropertyChangeListener cannot be null

java.lang.IllegalArgumentException - The listener is already registered with the given name

addPropertyChangeListener

public void addPropertyChangeListener(java.lang.String propertyName,
                                      IPropertyChangeListener<?> listener)

Registers the given IPropertyChangeListener for the specified property. The listener will be notified only for changes to the specified property.

Parameters:

propertyName - The name of the property for which the listener was registered

listener - The listener to be notified upon changes

Throws:

java.lang.NullPointerException - IPropertyChangeListener cannot be null

java.lang.IllegalArgumentException - The listener is already registered with the property name

canMoveDown

public <T> boolean canMoveDown(java.util.List<T> list,
                               T stateObject)

Determines whether the given item can be moved down by one position in the list owned by its parent.

Parameters:

list - The list used to determine if the given item can be moved down in that list

stateObject - The item that could potentially be moved down

Returns:

true if the object can be moved down by one unit; false otherwise

canMoveUp

public <T> boolean canMoveUp(java.util.List<T> list,
                             T item)

Determines whether the given item can be moved up by one position in the list owned by its parent.

Parameters:

list - The list used to determine if the given item can be moved up in that list

item - The item that could potentially be moved up

Returns:

true if the object can be moved up by one unit; false otherwise

fireListChangeEvent

protected <T> void fireListChangeEvent(IListChangeEvent<T> event)

firePropertyChanged

public void firePropertyChanged(java.lang.String propertyName,
                                java.lang.Object oldValue,
                                java.lang.Object newValue)

Notifies the IPropertyChangeListeners that have been registered with the given property name that the property has changed.

Parameters:

propertyName - The name of the property associated with the property change

oldValue - The old value of the property that changed

newValue - The new value of the property that changed

hasListChangeListeners

public boolean hasListChangeListeners(java.lang.String listName)

Determines whether there are at least one IListChangeListener registered to listen for changes made to the list with the given list name.

Parameters:

listName - The name of the list to check if it has registered listeners

Returns:

true if listeners have been registered for the given list name; false otherwise

hasListeners

protected boolean hasListeners(java.util.Map<java.lang.String,?> listeners,
                               java.lang.String name)

Determines whether there are at least one listener registered.

Parameters:

name - The name of the property or list to check if it has registered listeners

Returns:

true if listeners have been registered for the given name; false otherwise

hasPropertyChangeListeners

public boolean hasPropertyChangeListeners(java.lang.String propertyName)

Determines whether there are at least one IPropertyChangeListener registered to listen for changes made to the property with the given property name.

Parameters:

propertyName - The name of the property to check if it has registered listeners

Returns:

true if listeners have been registered for the given property name; false otherwise

initialize

protected void initialize(StateObject source)

Initializes this ChangeSupport.

Parameters:

source - The object for which this object will take care of notifying the listeners upon changes made to the object's internal state

Throws:

java.lang.NullPointerException - The source StateObject cannot be null

listChangeListeners

protected <T> ListIterable<IListChangeListener<T>> listChangeListeners(java.lang.String listName)

moveDown

public <T> void moveDown(ListHolderStateObject<T> source,
                         java.util.List<T> items,
                         java.lang.String listName,
                         T item)

Moves the given StateObject down by one position in the list owned by its parent.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of items to which the child is moved down

listName - The name associated with the list

item - The child to move down within the list

moveItem

protected <T> void moveItem(ListHolderStateObject<T> source,
                            java.util.List<T> items,
                            IListChangeEvent.EventType eventType,
                            java.lang.String listName,
                            T item,
                            int oldIndex,
                            int newIndex)

Moves the given item from its current position to a new position in the list owned by its parent.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of items to which the child is moved

eventType - The type describing how the item was moved (up or down)

listName - The name associated with the list

item - The child to move within the list

oldIndex - The current position of the item to move

newIndex - The new position within the list

moveUp

public <T> void moveUp(ListHolderStateObject<T> source,
                       java.util.List<T> items,
                       java.lang.String listName,
                       T item)

Moves the given item up by one position in the list owned by its parent.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of items to which the child is moved up

listName - The name associated with the list

item - The child to move up within the list

propertyChangeListeners

protected ListIterable<IPropertyChangeListener<?>> propertyChangeListeners(java.lang.String propertyName)

removeItem

public <T> void removeItem(ListHolderStateObject<T> source,
                           java.util.List<T> items,
                           java.lang.String listName,
                           T item)

Removes the given item from the list of children.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of item to which the child is removed

listName - The name associated with the list

item - The child to removed from the list

removeItems

public <T> void removeItems(ListHolderStateObject<T> source,
                            java.util.List<? extends T> list,
                            java.lang.String listName,
                            java.util.Collection<? extends T> items)

Removes the given items from the list of children.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

list - The list of items to which the child is removed

listName - The name associated with the list

items - The items to removed from the list

removeListChangeListener

public void removeListChangeListener(java.lang.String listName,
                                     IListChangeListener<?> listener)

Unregisters the given IListChangeListener that was registered for the specified list. The listener will no longer be notified only when items are added, removed, moved from the list.

Parameters:

listName - The name of the list for which the listener was registered

listener - The listener to unregister

Throws:

java.lang.NullPointerException - IListChangeListener cannot be null

java.lang.IllegalArgumentException - The listener was never registered with the list name

removeListener

protected <T> void removeListener(java.util.Map<java.lang.String,java.util.List<T>> listeners,
                                  java.lang.Class<?> listenerType,
                                  java.lang.String name,
                                  T listener)

Unregisters the given listener that was registered for the specified name. The listener will no longer be notified upon changes.

Parameters:

listeners - The list of listeners from which the given listener is removed

listenerType - The type of the listener, which is only used in the exception's message

name - The name of the event for which the listener was registered

listener - The listener to unregister

Throws:

java.lang.NullPointerException - IPropertyChangeListener cannot be null

java.lang.IllegalArgumentException - The listener was never registered with the given name

removePropertyChangeListener

public void removePropertyChangeListener(java.lang.String propertyName,
                                         IPropertyChangeListener<?> listener)

Unregisters the given IPropertyChangeListener that was registered for the specified property. The listener will no longer be notified when the property changes.

Parameters:

propertyName - The name of the property for which the listener was registered

listener - The listener to unregister

Throws:

java.lang.NullPointerException - IPropertyChangeListener cannot be null

java.lang.IllegalArgumentException - The listener was never registered with the property name

replaceItem

public <T> void replaceItem(ListHolderStateObject<T> source,
                            java.util.List<T> items,
                            java.lang.String listName,
                            int index,
                            T item)

Replaces the item at the given position by a new one.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of items to which a child is replaced

listName - The name associated with the list

index - The position of the item to replace

item - The item to replace the one at the given position

replaceItems

public <T> void replaceItems(ListHolderStateObject<T> source,
                             java.util.List<T> items,
                             java.lang.String listName,
                             java.util.List<T> newItems)

Replaces the given list by removing any existing items and adding the items contained in the second list.

Type Parameters:

T - The type of the items

Parameters:

source - The ListHolderStateObject from where the change is coming

items - The list of items to which the child is removed

listName - The name associated with the list

newItems - The items to removed from the list