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/ViewerComparator.java
/*******************************************************************************
 * Copyright (c) 2006 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 ******************************************************************************/
package org.eclipse.jface.viewers;
import java.util.Arrays;
import java.util.Comparator;
import org.eclipse.jface.util.Policy;
/**
 * A viewer comparator is used by a {@link StructuredViewer} to
 * reorder the elements provided by its content provider.
 * <p>
 * The default <code>compare</code> method compares elements using two steps. 
 * The first step uses the values returned from <code>category</code>. 
 * By default, all elements are in the same category. 
 * The second level is based on a case insensitive compare of the strings obtained 
 * from the content viewer's label provider via <code>ILabelProvider.getText</code>.