TileDistanceSort.java

/*
 * Copyright 2013 Hannes Janetzek
 *
 * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
 *
 * This program is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.oscim.layers.tile;

import java.util.Comparator;

import org.oscim.utils.TimSort;

public class TileDistanceSort extends TimSort<MapTile> {

	static TileDistanceSort INSTANCE = new TileDistanceSort();

	private TileDistanceSort() {
		super();
	}

	public static void sort(MapTile[] a, int lo, int hi) {
		int nRemaining = hi - lo;
		if (nRemaining < 2) {
			return;
		}

		synchronized (INSTANCE) {
			INSTANCE.doSort(a, DistanceComparator, lo, hi);
		}
	}

	final static Comparator<MapTile> DistanceComparator = new Comparator<MapTile>() {
		@Override
		public int compare(MapTile a, MapTile b) {
			if (a == null) {
				if (b == null)
					return 0;

				return 1;
			}
			if (b == null)
				return -1;

			if (a.distance < b.distance) {
				return -1;
			}
			if (a.distance > b.distance) {
				return 1;
			}
			return 0;
		}
	};
}