Bug 38247 [Viewers] [Javadoc] Incomplete javadoc for DialogCellEditor
The javadoc for #openDialogBox() does not say how to indicate that the dialog box was canceled. The de-facto behaviour is that if null is returned, it is considered as "cancel".
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/DialogCellEditor.java
fireCancelEditor();
			}
		}
	});
	button.addSelectionListener(new SelectionAdapter() {
		public void widgetSelected(SelectionEvent event) {
			Object newValue = openDialogBox(editor);
			if (newValue != null) {
				boolean newValidState = isCorrect(newValue);
				if (newValidState) {
					markDirty();
					doSetValue(newValue);
				} else {
					
					setErrorMessage(MessageFormat.format(getErrorMessage(), new Object[] { newValue.toString()}));
				}
				fireApplyEditorValue();
			}
		}
	});
	setValueValid(true);
	return editor;
}
/* (non-Javadoc)
 * Method declared on CellEditor.
 */
protected Object doGetValue() {
	return value;
}
/* (non-Javadoc)