Bug 163317 [Viewers] Take over SWT programming pattern to JFace Viewers
To open ColumnViewer for reusablility we should not make it final making the constructor protected forces people to subclass it and not directly creating instances from it.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/CellLabelProvider.java
/**
	 * The foreground color used to display the the text in the tool tip
	 * 
	 * @param object
	 *            the {@link Object} for which the tool tip is shown
	 * @return the {@link Color} used or <code>null</code> if you want to use
	 *         the default color {@link SWT#COLOR_INFO_FOREGROUND}
	 * @see SWT#COLOR_INFO_FOREGROUND
	 */
	public Color getToolTipForegroundColor(Object object) {
		return null;
	}
	/**
	 * Get the {@link Font} used to display the tool tip
	 * 
	 * @param object
	 *            the element for which the tool tip is shown
	 * @return {@link Font} or <code>null</code> if the default font is to be
	 *         used.
	 */
	public Font getToolTipFont(Object object) {
		return null;
	}
	/**
	 * Return the amount of pixels in x and y direction you want the tool tip to
	 * pop up from the mouse pointer. The default shift is 10px right and 0px
	 * below your mouse cursor. Be aware of the fact that you should at least
	 * position the tool tip 1px right to your mouse cursor else click events
	 * may not get propagated properly.
	 *