org.eclipse.core.commands.operations

Class ObjectUndoContext

java.lang.Object

org.eclipse.core.commands.operations.UndoContext

org.eclipse.core.commands.operations.ObjectUndoContext

All Implemented Interfaces:

IUndoContext

public final class ObjectUndoContext
extends UndoContext

An undo context that can be used to represent any given object. Clients can add matching contexts to this context. This class may be instantiated by clients.

Since:

3.1

Constructor Summary

Constructors

Constructor and Description
ObjectUndoContext(Object object) Construct an operation context that represents the given object.
ObjectUndoContext(Object object, String label) Construct an operation context that represents the given object and has a specialized label.

Method Summary

Modifier and Type	Method and Description
void	addMatch(IUndoContext context) Add the specified context as a match of this context.
String	getLabel() Get the label that describes the undo context.
Object	getObject() Return the object that is represented by this context.
boolean	matches(IUndoContext context) Return whether the specified context is considered a match for the receiving context.
void	removeMatch(IUndoContext context) Remove the specified context as a match of this context.
String	toString() The string representation of this operation.

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectUndoContext

public ObjectUndoContext(Object object)

Construct an operation context that represents the given object.

Parameters:

object - the object to be represented.

ObjectUndoContext

public ObjectUndoContext(Object object,
                         String label)

Construct an operation context that represents the given object and has a specialized label.

Parameters:

object - the object to be represented.

label - the label for the context

Method Detail

getLabel

public String getLabel()

Description copied from class: UndoContext

Get the label that describes the undo context. The default implementation returns the empty String. Subclasses may override.

Specified by:

getLabel in interface IUndoContext

Overrides:

getLabel in class UndoContext

Returns:

the label for the context.

getObject

public Object getObject()

Return the object that is represented by this context.

Returns:

the object represented by this context.

addMatch

public void addMatch(IUndoContext context)

Add the specified context as a match of this context. Contexts added as matches of this context will be interpreted as a match of this context when the history is filtered for a particular context. Adding a match allows components to create their own contexts for implementing specialized behavior, yet have their operations appear in a more global context.

Parameters:

context - the context to be added as a match of this context

removeMatch

public void removeMatch(IUndoContext context)

Remove the specified context as a match of this context. The context will no longer be interpreted as a match of this context when the history is filtered for a particular context. This method has no effect if the specified context was never previously added as a match.

Parameters:

context - the context to be removed from the list of matches for this context

matches

public boolean matches(IUndoContext context)

Description copied from class: UndoContext

Return whether the specified context is considered a match for the receiving context. When a context matches another context, operations that have the context are considered to also have the matching context. The default implementation checks whether the supplied context is identical to this context. Subclasses may override.

Specified by:

matches in interface IUndoContext

Overrides:

matches in class UndoContext

Parameters:

context - the context to be checked against the receiving context.

Returns:

true if the receiving context can be considered a match for the specified context, and false if it cannot.

toString

public String toString()

The string representation of this operation. Used for debugging purposes only. This string should not be shown to an end user.

Overrides:

toString in class Object

Returns:

The string representation.