| /******************************************************************************* |
| * 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.ui.internal.services; |
| |
| import java.util.Comparator; |
| |
| import org.eclipse.ui.internal.util.Util; |
| |
| /** |
| * <p> |
| * Compares two evaluation result caches ({@link IEvaluationResultCache}). The |
| * cache with the lowest source priority is considered "greater". In the event |
| * of a tie, other characteristics are checked. |
| * </p> |
| * <p> |
| * This class is only intended for use within the |
| * <code>org.eclipse.ui.workbench</code> plug-in. |
| * </p> |
| * |
| * @since 3.2 |
| * |
| */ |
| public final class EvaluationResultCacheComparator implements Comparator { |
| |
| public final int compare(final Object object1, final Object object2) { |
| if (Util.equals(object2, object1)) { |
| return 0; |
| } |
| |
| final IEvaluationResultCache cache1 = (IEvaluationResultCache) object1; |
| final IEvaluationResultCache cache2 = (IEvaluationResultCache) object2; |
| int comparison; |
| |
| /* |
| * Note: all of the comparisons are flipped intentionally. This allows |
| * those items with greater values to appear earlier when using an |
| * iterator. |
| */ |
| // if objects went to the trouble to implement Comparable |
| // we should use it ... this algorithm can accept a natural ordering |
| // that's not compatible with equals. |
| if (object1 instanceof Comparable && object2 instanceof Comparable) { |
| comparison = Util.compare((Comparable) object2, |
| (Comparable) object1); |
| if (comparison != 0) { |
| return comparison; |
| } |
| } |
| |
| return Util.compareIdentity(cache2, cache1); |
| } |
| } |
| |
