Bug 128298 ViewerSorter.compare() does not need to be overridden from superclass
The ViewerComparator class was added as a superclass of ViewerSorter (for ICU4J). ViewerSorter overrides compare() from ViewerComparator, but this is not necessary if in the superclass implementation getComparator().compare() is called, instead of comparator.compare().
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ViewerSorter.java
} else {
                name1 = e1.toString();
                name2 = e2.toString();
            }
        }
        if (name1 == null)
            name1 = "";
        if (name2 == null)
            name2 = "";
        
        
        return collator.compare(name1, name2);
    }
    /**
     * Returns the collator used to sort strings.
     *
     * @return the collator used to sort strings
     */
    public Collator getCollator() {
        return collator;
    }
	
	/* (non-Javadoc)
	 * @see org.eclipse.jface.viewers.ViewerComparator#getComparator()
	 */
	protected Comparator getComparator() {
		return getCollator();
	}
}