org.eclipse.mylyn.discovery.core/src/org/eclipse/mylyn/internal/discovery/core/util/DiscoveryCategoryComparator.java

/*******************************************************************************
 * Copyright (c) 2009 Tasktop Technologies and others.
 * 
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * https://www.eclipse.org/legal/epl-2.0
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *     Tasktop Technologies - initial API and implementation
 *******************************************************************************/
package org.eclipse.mylyn.internal.discovery.core.util;

import java.util.Comparator;

import org.eclipse.mylyn.internal.discovery.core.model.DiscoveryCategory;

/**
 * A comparator that orders categories by relevance and name.
 * 
 * @author David Green
 */
public class DiscoveryCategoryComparator implements Comparator<DiscoveryCategory> {

	public int compare(DiscoveryCategory o1, DiscoveryCategory o2) {
		if (o1 == o2) {
			return 0;
		}
		String r1 = o1.getRelevance();
		String r2 = o2.getRelevance();
		int i;
		if (r1 != null && r2 != null) {
			// don't have to worry about format, since they were already validated
			// note that higher relevance appears first, thus the reverse order of
			// the comparison.
			i = Integer.valueOf(r2).compareTo(Integer.valueOf(r1));
		} else if (r1 == null) {
			return 1;
		} else {
			return -1;
		}
		if (i == 0) {
			i = o1.getName().compareToIgnoreCase(o2.getName());
			if (i == 0) {
				i = o1.getId().compareTo(o2.getId());
			}
		}
		return i;
	}

}