nextapp.echo.app.update
Class ServerComponentUpdate

java.lang.Object
  nextapp.echo.app.update.ServerComponentUpdate

All Implemented Interfaces:

java.io.Serializable

public class ServerComponentUpdate
extends java.lang.Object
implements java.io.Serializable

A description of a server-side update to a single component, i.e., an update which has occurred on the server and must be propagated to the client. Describes the addition and removal of children to the component. Describes modifications to properties of the component. Describes modifications to the LayoutData states of children of the component.

See Also:

Serialized Form

Constructor Summary

ServerComponentUpdate(Component parent)
Creates a new ServerComponentUpdate representing the given parent Component.

Method Summary

void	addChild(Component child) Adds a description of an added child to the ServerComponentUpdate.
void	appendRemovedDescendants(ServerComponentUpdate update) Appends the removed child and descendant components of the given ServerComponentUpdate to this ServerComponentUpdate's list of removed descendants.
void	cancelUpdateProperty(java.lang.String propertyName) Cancels an update to a property.
Component[]	getAddedChildren() Returns the child components which have been added to the parent.
Component	getParent() Returns the parent component being updated.
Component[]	getRemovedChildren() Returns the child components which have been removed from the parent.
Component[]	getRemovedDescendants() Returns all descendants of the child components which have been removed from the parent.
Component[]	getUpdatedLayoutDataChildren() Returns the child components whose LayoutData properties have been updated.
PropertyUpdate	getUpdatedProperty(java.lang.String name) Returns a PropertyUpdate describing an update to the property with the given name.
java.lang.String[]	getUpdatedPropertyNames() Returns the names of all properties being updated in this update.
boolean	hasAddedChild(Component component) Determines if the specified component has been added as a child in this update.
boolean	hasAddedChildren() Determines if the update is adding any children to the parent component.
boolean	hasRemovedChild(Component component) Determines if the specified child was removed from the parent component.
boolean	hasRemovedChildren() Determines if the update is removing children from the parent component.
boolean	hasRemovedDescendant(Component component) Determines if the specified component is a removed child or descendant of the parent component.
boolean	hasRemovedDescendants() Determines if the update is removing children from the parent that have descendants.
boolean	hasUpdatedLayoutDataChildren() Determines if the update has child components whose LayoutData states have changed.
boolean	hasUpdatedProperties() Determines if the update is updating properties of the parent component.
boolean	hasUpdatedProperty(java.lang.String propertyName) Determines if the update is updating a specific property of the parent component.
void	removeChild(Component child) Adds a description of a removed child to the ServerComponentUpdate.
void	removeDescendant(Component descendant) Recursive method to add descriptions of descendants which were removed.
java.lang.String	toString() Display debug representation.
void	updateLayoutData(Component child) Adds a description of an update to a child component's LayoutData information to the ServerComponentUpdate.
void	updateProperty(java.lang.String propertyName, java.lang.Object oldValue, java.lang.Object newValue) Adds a description of an update to a property of the parent component to the ServerComponentUpdate.

Methods inherited from class java.lang.Object

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

Constructor Detail

ServerComponentUpdate

public ServerComponentUpdate(Component parent)

Creates a new ServerComponentUpdate representing the given parent Component.

Parameters:

parent - the updating parent Component

Method Detail

addChild

public void addChild(Component child)

Adds a description of an added child to the ServerComponentUpdate.

Parameters:

child - the child being added

cancelUpdateProperty

public void cancelUpdateProperty(java.lang.String propertyName)

Cancels an update to a property. A cancellation of a property update is performed when the update manager discovers that the state of a property is already correct on the client.

Parameters:

propertyName - the property update to cancel

appendRemovedDescendants

public void appendRemovedDescendants(ServerComponentUpdate update)

Appends the removed child and descendant components of the given ServerComponentUpdate to this ServerComponentUpdate's list of removed descendants. This method is invoked by the ServerUpdateManager when a component is removed that is an ancestor of a component that has been updated. In such a case, the descendant ServerComponentUpdate is destroyed, and thus its removed descendant components must be stored in the ancestor ServerComponentUpdate.

Parameters:

update - the ServerComponentUpdate whose removed descendants are to be appended

getAddedChildren

public Component[] getAddedChildren()

Returns the child components which have been added to the parent.

Returns:

the added child components

getParent

public Component getParent()

Returns the parent component being updated.

Returns:

the parent component

getRemovedChildren

public Component[] getRemovedChildren()

Returns the child components which have been removed from the parent. These components may or may not have ever been rendered by the container, e.g., if a component was added and removed in a single synchronization it will show up as a removed component even though the container may have never rendered it.

Returns:

the removed child components

See Also:

getRemovedDescendants()

getRemovedDescendants

public Component[] getRemovedDescendants()

Returns all descendants of the child components which have been removed from the parent. This returned array DOES NOT contain the children which were directly removed from the parent component. These components may or may not have ever been rendered by the container, e.g., if a component was added and removed in a single synchronization it will show up as a removed descendant even though the container may have never rendered it.

Returns:

the removed descendant components

See Also:

getRemovedChildren()

getUpdatedLayoutDataChildren

public Component[] getUpdatedLayoutDataChildren()

Returns the child components whose LayoutData properties have been updated.

Returns:

the changed child components

getUpdatedProperty

public PropertyUpdate getUpdatedProperty(java.lang.String name)

Returns a PropertyUpdate describing an update to the property with the given name.

Parameters:

name - the name of the property being updated

Returns:

the PropertyUpdate, or null if none exists

See Also:

getUpdatedPropertyNames()

getUpdatedPropertyNames

public java.lang.String[] getUpdatedPropertyNames()

Returns the names of all properties being updated in this update.

Returns:

the names of all updated properties

See Also:

getUpdatedPropertyNames()

hasAddedChild

public boolean hasAddedChild(Component component)

Determines if the specified component has been added as a child in this update.

Parameters:

component - the component to test

Returns:

true if the component was added

hasAddedChildren

public boolean hasAddedChildren()

Determines if the update is adding any children to the parent component.

Returns:

true if children are being added

hasRemovedChild

public boolean hasRemovedChild(Component component)

Determines if the specified child was removed from the parent component.

Parameters:

component - the potentially removed child

Returns:

true if the child was removed

hasRemovedChildren

public boolean hasRemovedChildren()

Determines if the update is removing children from the parent component.

Returns:

true if children are being removed

hasRemovedDescendant

public boolean hasRemovedDescendant(Component component)

Determines if the specified component is a removed child or descendant of the parent component.

Parameters:

component - the potentially removed child/descendant

Returns:

true if the component is a removed child/descendant

hasRemovedDescendants

public boolean hasRemovedDescendants()

Determines if the update is removing children from the parent that have descendants. Having removed descendants implies having removed children. If none of the children being removed have children, this method will return false.

Returns:

true if descendants are being removed

hasUpdatedLayoutDataChildren

public boolean hasUpdatedLayoutDataChildren()

Determines if the update has child components whose LayoutData states have changed.

Returns:

true if LayoutData properties are being updated

hasUpdatedProperties

public boolean hasUpdatedProperties()

Determines if the update is updating properties of the parent component.

Returns:

true if properties are being updated

hasUpdatedProperty

public boolean hasUpdatedProperty(java.lang.String propertyName)

Determines if the update is updating a specific property of the parent component.

Parameters:

propertyName - the property name

Returns:

true if the specified property is being updated

removeChild

public void removeChild(Component child)

Adds a description of a removed child to the ServerComponentUpdate.

Parameters:

child - the child being removed

removeDescendant

public void removeDescendant(Component descendant)

Recursive method to add descriptions of descendants which were removed.

Parameters:

descendant - the removed descendant

toString

public java.lang.String toString()

Display debug representation.

Overrides:

toString in class java.lang.Object

See Also:

Object.toString()

updateLayoutData

public void updateLayoutData(Component child)

Adds a description of an update to a child component's LayoutData information to the ServerComponentUpdate.

Parameters:

child - the updated child

updateProperty

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

Adds a description of an update to a property of the parent component to the ServerComponentUpdate.

Parameters:

propertyName - the name of the property

oldValue - the previous value of the property

newValue - the current value of the property