com.ibm.xtools.mmi.core.delta

Class ModelChangeDelta

java.lang.Object

com.ibm.xtools.mmi.core.delta.ModelChangeDelta

Direct Known Subclasses:

CompoundModelChangeDelta

public class ModelChangeDelta
extends java.lang.Object

Representation of a delta in a model created by changes invoked via the user interface or by code.

This class (and its subclass CompoundModelChangeDelta) is intended to encapsulate all data related to a change in a MMI model. These changes are brought about either via user actions, or through executed commands.

ModelChangeDeltas are used by implementations of the ISourceSynchronizationProvider interface to apply changes to source models as a result of changes to a model. ModelChangeDeltas are created in two places during such operations: Once during validation, in the VizElementValidator and once during command execution, in the ModelChangeListener when undo intervals are closed.

See Also:

CompoundModelChangeDelta, ModelChangeListener, ISourceSynchronizationProvider, SourceSynchronizationService

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Collection	collection For an add operation, this is the collection of objects being added to the owner list.
protected org.eclipse.emf.ecore.EStructuralFeature	feature This is the feature of the owner object upon which the operation was performed.
protected int	index For an add operation, this is the position at which the objects were inserted.
protected int[]	indices Where the represented delta involves a collection, this is the array of indices that were affected by the operation.
protected int	oldIndex For a move operation, this is the source position for the moved object.
protected java.lang.Object	oldValue The previous value in an add/set operation, the removed value in a remove operation.
protected org.eclipse.emf.ecore.EObject	owner This is the owner object upon which the operation was performed.
protected java.util.Set	participantIDs
protected int	type The type of operation represented by this delta.
protected java.lang.Object	value The value that was added/set by the operation represented by this delta.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ModelChangeDelta() Zero argument constructor for the ModelChangeDelta type.
protected	ModelChangeDelta(int t) Constructor for the ModelChangeDelta type.

Method Summary

Modifier and Type	Method and Description
void	addParticipantID(java.lang.String id) Adds a participant identifier string to this ModelChangeDelta.
static boolean	affectsVizElements(org.eclipse.emf.common.notify.Notification notification) Test method to determine whether or not a particular Notification represents a change to the model.
static ModelChangeDelta	createModelChangeDelta(java.util.List notifications) Static factory method that creates a ModelChangeDelta from a List of EMF Notifications.
static ModelChangeDelta	createModelChangeDelta(org.eclipse.emf.common.notify.Notification notification) Static factory method that creates a ModelChangeDelta from an EMF Notification.
void	dispose() Cleans up this ModelChangeDelta instance when it is no longer needed.
java.util.Collection	getCollection()
org.eclipse.emf.ecore.EStructuralFeature	getFeature()
int	getIndex()
int[]	getIndices()
int	getOldIndex()
java.lang.Object	getOldValue()
org.eclipse.emf.ecore.EObject	getOwner()
java.util.Set	getParticipantIDs() Gets the Set of participant identifiers that participate in this ModelChangeDelta
int	getType()
java.lang.Object	getValue()
boolean	isCompound()
java.lang.String	toString() Generates a String representation of this ModelChangeDelta suitable for debug purposes only.
ModelChangeDelta	unwrap()

Methods inherited from class java.lang.Object

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

Field Detail

participantIDs

protected java.util.Set participantIDs

owner

protected org.eclipse.emf.ecore.EObject owner

This is the owner object upon which the operation was performed.

feature

protected org.eclipse.emf.ecore.EStructuralFeature feature

This is the feature of the owner object upon which the operation was performed.

collection

protected java.util.Collection collection

For an add operation, this is the collection of objects being added to the owner list. For a remove operation, this is the collection of objects being removed from the owner list. May be null, in which case a single value was affected by the operation.

index

protected int index

For an add operation, this is the position at which the objects were inserted. For a remove operation, this is the position at which objects were removed. For a move operation, this is the destination position for the moved object.

oldIndex

protected int oldIndex

For a move operation, this is the source position for the moved object.

indices

protected int[] indices

Where the represented delta involves a collection, this is the array of indices that were affected by the operation.

value

protected java.lang.Object value

The value that was added/set by the operation represented by this delta.

oldValue

protected java.lang.Object oldValue

The previous value in an add/set operation, the removed value in a remove operation.

type

protected int type

The type of operation represented by this delta.

Constructor Detail

ModelChangeDelta

protected ModelChangeDelta(int t)

Constructor for the ModelChangeDelta type.

Parameters:

t - -- The MCommand.Type type of operation that this ModelChangeDelta instance is to represent.

ModelChangeDelta

protected ModelChangeDelta()

Zero argument constructor for the ModelChangeDelta type.

Method Detail

createModelChangeDelta

public static final ModelChangeDelta createModelChangeDelta(java.util.List notifications)

Static factory method that creates a ModelChangeDelta from a List of EMF Notifications.

This method takes a List of Notifications as an input and extracts all relevant information on the changes to the model that have been applied. The extracted information is wrapped in one or more ModelChangeDelta or CompoundModelChangeDelta elements and returned.

Parameters:

notifications - -- The List of Notifications for which delta information is to be generated.

Returns:

A ModelChangeDelta instance representing the changes to the model described by the provided Notifications, or null if the provided Notifications represent no changes to the model.

createModelChangeDelta

public static final ModelChangeDelta createModelChangeDelta(org.eclipse.emf.common.notify.Notification notification)

Static factory method that creates a ModelChangeDelta from an EMF Notification.

Parameters:

notification - -- The Notification for which delta information is to be generated.

Returns:

A ModelChangeDelta instance representing the change to the model described by the provided Notification, or null if the provided Notification represents no change to the model.

affectsVizElements

public static final boolean affectsVizElements(org.eclipse.emf.common.notify.Notification notification)

Test method to determine whether or not a particular Notification represents a change to the model.

Parameters:

notification - -- the notification instance to be tested.

Returns:

true iff the specified Notification instance affects the model.

addParticipantID

public void addParticipantID(java.lang.String id)

Adds a participant identifier string to this ModelChangeDelta. A participant identifier is a unique String whose value is used to bind an IStructuredReferenceHandler to a particular source model type.

Parameters:

id - -- The IStructuredReferenceHandler's identifier string.

See Also:

IStructuredReferenceHandler

getParticipantIDs

public java.util.Set getParticipantIDs()

Gets the Set of participant identifiers that participate in this ModelChangeDelta

Returns:

Set -- The set of participant identifiers for this ModelChangeDelta

See Also:

addParticipantID(String id)

getType

public int getType()

Returns:

Returns the MCommand.Type type of operation represented by this ModelChangeDelta

getCollection

public final java.util.Collection getCollection()

Returns:

Returns the collection.

getFeature

public final org.eclipse.emf.ecore.EStructuralFeature getFeature()

Returns:

Returns the feature.

getIndex

public final int getIndex()

Returns:

Returns the index.

getIndices

public final int[] getIndices()

Returns:

Returns the indices.

getOldIndex

public final int getOldIndex()

Returns:

Returns the oldIndex.

getOldValue

public final java.lang.Object getOldValue()

Returns:

Returns the oldValue.

getOwner

public final org.eclipse.emf.ecore.EObject getOwner()

Returns:

Returns the owner.

getValue

public final java.lang.Object getValue()

Returns:

Returns the value.

isCompound

public boolean isCompound()

Returns:

Returns true when this ModelChangeDelta is compound.

dispose

public void dispose()

Cleans up this ModelChangeDelta instance when it is no longer needed.

unwrap

public ModelChangeDelta unwrap()

Returns:

this

See Also:

CompoundModelChangeDelta.unwrap()

toString

public java.lang.String toString()

Generates a String representation of this ModelChangeDelta suitable for debug purposes only.

Overrides:

toString in class java.lang.Object