define distances between shipments and services

jsprit-core/src/main/java/algorithms/AvgJobDistance.java

@@ -0,0 +1,104 @@
+/*******************************************************************************
+ * Copyright (C) 2013  Stefan Schroeder
+ * 
+ * This library 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 3.0 of the License, or (at your option) any later version.
+ * 
+ * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ ******************************************************************************/
+package algorithms;
+
+import org.apache.log4j.Logger;
+
+import util.Coordinate;
+import util.EuclideanDistanceCalculator;
+import basics.Job;
+import basics.Service;
+import basics.Shipment;
+import basics.costs.VehicleRoutingTransportCosts;
+
+
+/**
+ * Calculator that calculates average distance between two jobs based on the input-transport costs.
+ * 
+ * <p>If the distance between two jobs cannot be calculated with input-transport costs, it tries the euclidean distance between these jobs.
+ * 
+ * @author stefan schroeder
+ *
+ */
+class AvgJobDistance implements JobDistance {
+
+	private static Logger log = Logger.getLogger(AvgJobDistance.class);
+	
+	private VehicleRoutingTransportCosts costs;
+
+	public AvgJobDistance(VehicleRoutingTransportCosts costs) {
+		super();
+		this.costs = costs;
+
+	}
+
+	/**
+	 * Calculates and returns the average distance between two jobs based on the input-transport costs.
+	 * 
+	 * <p>If the distance between two jobs cannot be calculated with input-transport costs, it tries the euclidean distance between these jobs.
+	 */ 
+	@Override
+	public double calculateDistance(Job i, Job j) {
+		if (i.equals(j)) return 0.0;
+
+		if (i instanceof Service && j instanceof Service) {
+			return calcDist((Service)i, (Service)j);
+		} 
+		else if(i instanceof Service && j instanceof Shipment){
+			return calcDist((Service)i,(Shipment)j);
+		}
+		else if(i instanceof Shipment && j instanceof Service){
+			return calcDist((Service)j,(Shipment)i);
+		}
+		else if(i instanceof Shipment && j instanceof Shipment){
+			return calcDist((Shipment)i,(Shipment)j);
+		}
+		else{
+			throw new IllegalStateException("this supports only shipments or services");
+		}
+	}
+
+	private double calcDist(Service i, Service j) {
+		return calcDist(i.getLocationId(),i.getCoord(),j.getLocationId(),j.getCoord());
+	}
+
+	private double calcDist(Service i, Shipment j) {
+		double c_ij1 = calcDist(i.getLocationId(),i.getCoord(),j.getPickupLocation(),j.getPickupCoord());
+		double c_ij2 = calcDist(i.getLocationId(),i.getCoord(),j.getDeliveryLocation(),j.getDeliveryCoord());
+		return (c_ij1 + c_ij2)/2.0;
+	}
+	
+	private double calcDist(Shipment i, Shipment j) {
+		double c_i1j1 = calcDist(i.getPickupLocation(),i.getPickupCoord(),j.getPickupLocation(),j.getPickupCoord());
+		double c_i1j2 = calcDist(i.getPickupLocation(),i.getPickupCoord(),j.getDeliveryLocation(),j.getDeliveryCoord());
+		double c_i2j1 = calcDist(i.getDeliveryLocation(),i.getDeliveryCoord(),j.getPickupLocation(),j.getPickupCoord());
+		double c_i2j2 = calcDist(i.getDeliveryLocation(),i.getDeliveryCoord(),j.getDeliveryLocation(),j.getDeliveryCoord());
+		return (c_i1j1 + c_i1j2 + c_i2j1 + c_i2j2)/4.0;
+	}
+
+	private double calcDist(String location_i, Coordinate coord_i, String location_j, Coordinate coord_j){
+		try{
+			double c_ij = costs.getTransportCost(location_i, location_j, 0.0, null, null);
+			return c_ij; 
+		}
+		catch(IllegalStateException e){
+			// now try the euclidean distance between these two services
+		}
+		double c_ij = EuclideanDistanceCalculator.calculateDistance(coord_i, coord_j);
+		return c_ij;
+	}
+}