javax.swing.text
Class AbstractDocument.DefaultDocumentEvent

java.lang.Object
  javax.swing.undo.AbstractUndoableEdit
      javax.swing.undo.CompoundEdit
          javax.swing.text.AbstractDocument.DefaultDocumentEvent

All Implemented Interfaces:

DocumentEvent, Serializable, UndoableEdit

Enclosing class:

AbstractDocument

public class AbstractDocument.DefaultDocumentEvent

extends CompoundEdit

implements DocumentEvent

Stores document changes as the document is being modified. Can subsequently be used for change notification when done with the document modification transaction. This is used by the AbstractDocument class and its extensions for broadcasting change information to the document listeners.

See Also:

Serialized Form

Nested Class Summary

Nested classes inherited from class javax.swing.event.DocumentEvent

DocumentEvent.ElementChange, DocumentEvent.EventType

Field Summary

private Hashtable	changeLookup
private int	length
private int	offset
private DocumentEvent.EventType	type

Fields inherited from class javax.swing.undo.CompoundEdit

edits

Fields inherited from class javax.swing.undo.AbstractUndoableEdit

RedoName, UndoName

Constructor Summary

AbstractDocument.DefaultDocumentEvent(int offs, int len, DocumentEvent.EventType type)
Constructs a change record.

Method Summary

boolean	addEdit(UndoableEdit anEdit) Adds a document edit.
DocumentEvent.ElementChange	getChange(Element elem) Gets the changes for an element.
Document	getDocument() Gets the document that sourced the change event.
int	getLength() Returns the length of the change.
int	getOffset() Returns the offset within the document of the start of the change.
String	getPresentationName() Provides a localized, human readable description of this edit suitable for use in, say, a change log.
String	getRedoPresentationName() Provides a localized, human readable description of the redoable form of this edit, e.g. for use as a Redo menu item.
DocumentEvent.EventType	getType() Returns the type of event.
String	getUndoPresentationName() Provides a localized, human readable description of the undoable form of this edit, e.g. for use as an Undo menu item.
boolean	isSignificant() DefaultDocument events are significant.
void	redo() Redoes a change.
String	toString() Returns a string description of the change event.
void	undo() Undoes a change.

Methods inherited from class javax.swing.undo.CompoundEdit

canRedo, canUndo, die, end, isInProgress, lastEdit

Methods inherited from class javax.swing.undo.AbstractUndoableEdit

replaceEdit

Methods inherited from class java.lang.Object

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

Field Detail

offset

private int offset

length

private int length

changeLookup

private Hashtable changeLookup

type

private DocumentEvent.EventType type

Constructor Detail

AbstractDocument.DefaultDocumentEvent

public AbstractDocument.DefaultDocumentEvent(int offs,
                                             int len,
                                             DocumentEvent.EventType type)

Constructs a change record.

Parameters:

offs - the offset into the document of the change >= 0

len - the length of the change >= 0

type - the type of event (DocumentEvent.EventType)

Method Detail

toString

public String toString()

Returns a string description of the change event.

Overrides:

toString in class CompoundEdit

Returns:

a string

addEdit

public boolean addEdit(UndoableEdit anEdit)

Adds a document edit. If the number of edits crosses a threshold, this switches on a hashtable lookup for ElementChange implementations since access of these needs to be relatively quick.

Specified by:

addEdit in interface UndoableEdit

Overrides:

addEdit in class CompoundEdit

Parameters:

anEdit - a document edit record

Returns:

true if the edit was added

redo

public void redo()
          throws CannotRedoException

Redoes a change.

Specified by:

redo in interface UndoableEdit

Overrides:

redo in class CompoundEdit

Throws:

CannotRedoException - if the change cannot be redone

undo

public void undo()
          throws CannotUndoException

Undoes a change.

Specified by:

undo in interface UndoableEdit

Overrides:

undo in class CompoundEdit

Throws:

CannotUndoException - if the change cannot be undone

isSignificant

public boolean isSignificant()

DefaultDocument events are significant. If you wish to aggregate DefaultDocumentEvents to present them as a single edit to the user place them into a CompoundEdit.

Specified by:

isSignificant in interface UndoableEdit

Overrides:

isSignificant in class CompoundEdit

Returns:

whether the event is significant for edit undo purposes

getPresentationName

public String getPresentationName()

Provides a localized, human readable description of this edit suitable for use in, say, a change log.

Specified by:

getPresentationName in interface UndoableEdit

Overrides:

getPresentationName in class CompoundEdit

Returns:

the description

getUndoPresentationName

public String getUndoPresentationName()

Provides a localized, human readable description of the undoable form of this edit, e.g. for use as an Undo menu item. Typically derived from getDescription();

Specified by:

getUndoPresentationName in interface UndoableEdit

Overrides:

getUndoPresentationName in class CompoundEdit

Returns:

the description

getRedoPresentationName

public String getRedoPresentationName()

Provides a localized, human readable description of the redoable form of this edit, e.g. for use as a Redo menu item. Typically derived from getPresentationName();

Specified by:

getRedoPresentationName in interface UndoableEdit

Overrides:

getRedoPresentationName in class CompoundEdit

Returns:

the description

getType

public DocumentEvent.EventType getType()

Returns the type of event.

Specified by:

getType in interface DocumentEvent

Returns:

the event type as a DocumentEvent.EventType

See Also:

DocumentEvent.getType()

getOffset

public int getOffset()

Returns the offset within the document of the start of the change.

Specified by:

getOffset in interface DocumentEvent

Returns:

the offset >= 0

See Also:

DocumentEvent.getOffset()

getLength

public int getLength()

Returns the length of the change.

Specified by:

getLength in interface DocumentEvent

Returns:

the length >= 0

See Also:

DocumentEvent.getLength()

getDocument

public Document getDocument()

Gets the document that sourced the change event.

Specified by:

getDocument in interface DocumentEvent

Returns:

the document

See Also:

DocumentEvent.getDocument()

getChange

public DocumentEvent.ElementChange getChange(Element elem)

Gets the changes for an element.

Specified by:

getChange in interface DocumentEvent

Parameters:

elem - the element

Returns:

the changes