Bug 164639 [JFace] improve usability of DefaultToolTip
DefaultToolTip should provide setters for the commonly-customized properties of the tooltip rather than rely on method subclassing.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ToolTipSupport.java
ViewerRow row = viewer.getViewerRow(new Point(event.x, event.y));
		viewer.getControl().setToolTipText(""); 
		Point point = new Point(event.x, event.y);
		if (row != null) {
			Object element = row.getItem().getData();
			ViewerColumn viewPart = viewer.getViewerColumn(row
					.getColumnIndex(point));
			if (viewPart == null) {
				return false;
			}
			CellLabelProvider labelProvider = viewPart.getLabelProvider();
			if (labelProvider.useNativeToolTip(element)) {
				String text = labelProvider.getToolTipText(element);
				if (text != null) {
					viewer.getControl().setToolTipText(text);
				}
				rv = false;
			} else {
				setPopupDelay(labelProvider.getToolTipDisplayDelayTime(element));
				setHideDelay(labelProvider.getToolTipTimeDisplayed(element));
				Point shift = labelProvider.getToolTipShift(element);
				if (shift == null) {
					setShift(new Point(DEFAULT_SHIFT_X, DEFAULT_SHIFT_Y));
				} else {
					setShift(new Point(shift.x, shift.y));
				}
				setData(LABEL_PROVIDER_KEY, labelProvider);
				setData(ELEMENT_KEY, element);
				rv = true;
			}