javax.swing.text.AbstractDocument#DefaultDocumentEvent ( )源码实例Demo

@Override
public void undoableEditHappened(UndoableEditEvent e) {
	//  Start a new compound edit

	if (compoundEdit == null) {
		compoundEdit = startCompoundEdit(e.getEdit());
		return;
	}

	int offsetChange = textComponent.getCaretPosition() - lastOffset;
	int lengthChange = textComponent.getDocument().getLength() - lastLength;

	//  Check for an attribute change
	UndoableEdit edit = e.getEdit();
	if (edit instanceof AbstractDocument.DefaultDocumentEvent) {
		AbstractDocument.DefaultDocumentEvent event = (AbstractDocument.DefaultDocumentEvent) e.getEdit();
		if (event.getType().equals(DocumentEvent.EventType.CHANGE)) {
			if (offsetChange == 0) {
				compoundEdit.addEdit(e.getEdit());
				return;
			}
		}
	}

	//  Check for an incremental edit or backspace.
	//  The Change in Caret position and Document length should both be
	//  either 1 or -1.
	if (offsetChange == lengthChange
			&& Math.abs(offsetChange) == 1) {
		compoundEdit.addEdit(e.getEdit());
		lastOffset = textComponent.getCaretPosition();
		lastLength = textComponent.getDocument().getLength();
		return;
	}

	//  Not incremental edit, end previous edit and start a new one
	compoundEdit.end();
	compoundEdit = startCompoundEdit(e.getEdit());
}
 

/**
 * The same as super.editToBeUndone() just that we treat DocumentEvent.EventType.CHANGE
 * the same way as true == edit.isSignificant().
 */
protected UndoableEdit editToBeUndone()
{
	UndoableEdit ue = super.editToBeUndone();

	if (ue == null)
	{
		return null;
	}

	int i = edits.indexOf(ue);
	while (i >= 0)
	{
		UndoableEdit edit = edits.elementAt(i--);
		if (edit.isSignificant())
		{
			if (edit instanceof AbstractDocument.DefaultDocumentEvent)
			{
				if (DocumentEvent.EventType.CHANGE != ((AbstractDocument.DefaultDocumentEvent)edit).getType())
				{
					return edit;
				}
			}
			else
			{
				return edit;
			}
		}
	}
	return null;
}
 

/**
 * The same as super.editToBeUndone() just that we treat DocumentEvent.EventType.CHANGE
 * the same way as true == edit.isSignificant().
 *
 * The method of the super class already seems to be a bit buggy.
 * The DocumentEvent.EventType.CHANGE fix doesn't remove the bugs but makes it behave
 */
protected UndoableEdit editToBeRedone()
{
	int count = edits.size();
	UndoableEdit ue = super.editToBeRedone();

	if (null == ue)
	{
		return null;
	}

	int i = edits.indexOf(ue);

	while (i < count)
	{
		UndoableEdit edit = edits.elementAt(i++);
		if (edit.isSignificant())
		{
			if (edit instanceof AbstractDocument.DefaultDocumentEvent)
			{
				if (DocumentEvent.EventType.CHANGE != ((AbstractDocument.DefaultDocumentEvent)edit).getType())
				{
					return edit;
				}
			}
			else
			{
				return edit;
			}
		}
	}
	return null;
}
 

@Override
public void undoableEditHappened(UndoableEditEvent ev) {
	UndoableEdit edit = ev.getEdit();
	if (edit instanceof AbstractDocument.DefaultDocumentEvent && ((AbstractDocument.DefaultDocumentEvent) edit)
			.getType() == AbstractDocument.DefaultDocumentEvent.EventType.CHANGE) {
		return;
	}
	manager.addEdit(edit);
}
 

@Override
public void undoableEditHappened(UndoableEditEvent e) {
   UndoableEdit edit=e.getEdit();
   if (edit instanceof AbstractDocument.DefaultDocumentEvent) {
      AbstractDocument.DefaultDocumentEvent event=(AbstractDocument.DefaultDocumentEvent)edit;
      int start=event.getOffset();
      int len=event.getLength();
      Debug.log(9, "undoableEditHappened " + start + "," + len);
      boolean isNeedStart=false;
      if(event.getType().equals(DocumentEvent.EventType.CHANGE) ||
         event.getType().equals(DocumentEvent.EventType.INSERT) ){
         try {
            String text=event.getDocument().getText(start, len);
            if (text.contains("\n"))
               isNeedStart=true;
         } catch (BadLocationException e1) {
           Debug.error(me + "undoableEditHappened: Problem getting text\n%s", e1.getMessage());
         }
      }

      if (current==null) {
         isNeedStart=true;
      }
      else if (lastEditName==null || !lastEditName.equals(edit.getPresentationName())) {
         isNeedStart=true;
      }

      while (pointer<edits.size()-1) {
         edits.remove(edits.size()-1);
         isNeedStart=true;
      }
      if (isNeedStart) {
         createCompoundEdit();
      }

      current.addEdit(edit);
      lastEditName=edit.getPresentationName();

      refreshControls();
   }
}
 

/**
 * Whenever an UndoableEdit happens the edit will either be absorbed by the
 * current compound edit or a new compound edit will be started
 */
@Override
public void undoableEditHappened(UndoableEditEvent e) {
    //  Start a new compound edit

    if (compoundEdit == null) {
        compoundEdit = startCompoundEdit(e.getEdit());
        startCombine = false;
        updateDirty();
        return;
    }
    if (e.getEdit() instanceof DefaultDocumentEvent) {
        // Java 6 to 8
        AbstractDocument.DefaultDocumentEvent docEvt = (DefaultDocumentEvent) e.getEdit();

        int editLine = doc.getLineNumberAt(docEvt.getOffset());

        //  Check for an incremental edit or backspace.
        //  The Change in Caret position and Document length should both be
        //  either 1 or -1.
        if ((startCombine || Math.abs(docEvt.getLength()) == 1) && editLine == lastLine) {
            compoundEdit.addEdit(e.getEdit());
            startCombine = false;
            updateDirty();
            return;
        }

        //  Not incremental edit, end previous edit and start a new one
        lastLine = editLine;

    } else // Java 9: It seems that all the edits are wrapped and we cannot get line number!
    // See https://github.com/netroby/jdk9-dev/blob/master/jdk/src/java.desktop/share/classes/javax/swing/text/AbstractDocument.java#L279
    // AbstractDocument.DefaultDocumentEventUndoableWrapper docEvt = e.getEdit();
    {
        if (startCombine && !e.getEdit().isSignificant()) {
            compoundEdit.addEdit(e.getEdit());
            startCombine = false;
            updateDirty();
            return;
        }
    }

    compoundEdit.end();
    compoundEdit = startCompoundEdit(e.getEdit());

    updateDirty();
}