added soft constraints

jsprit-examples/src/main/java/jsprit/examples/BuildAlgorithmFromScratchWithHardAndSoftConstraints.java

@@ -0,0 +1,219 @@
+/*******************************************************************************
+ * 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/>.
+ * 
+ * Contributors:
+ *     Stefan Schroeder - initial API and implementation
+ ******************************************************************************/
+package jsprit.examples;
+
+import java.util.Collection;
+
+import jsprit.analysis.toolbox.SolutionPrinter;
+import jsprit.core.algorithm.InsertionInitialSolutionFactory;
+import jsprit.core.algorithm.RemoveEmptyVehicles;
+import jsprit.core.algorithm.SearchStrategy;
+import jsprit.core.algorithm.SearchStrategyManager;
+import jsprit.core.algorithm.VariablePlusFixedSolutionCostCalculatorFactory;
+import jsprit.core.algorithm.VehicleRoutingAlgorithm;
+import jsprit.core.algorithm.acceptor.GreedyAcceptance;
+import jsprit.core.algorithm.module.RuinAndRecreateModule;
+import jsprit.core.algorithm.recreate.BestInsertionBuilder;
+import jsprit.core.algorithm.recreate.InsertionStrategy;
+import jsprit.core.algorithm.ruin.RadialRuinStrategyFactory;
+import jsprit.core.algorithm.ruin.RandomRuinStrategyFactory;
+import jsprit.core.algorithm.ruin.RuinStrategy;
+import jsprit.core.algorithm.ruin.distance.AvgServiceAndShipmentDistance;
+import jsprit.core.algorithm.selector.SelectBest;
+import jsprit.core.algorithm.state.StateManager;
+import jsprit.core.algorithm.state.UpdateVariableCosts;
+import jsprit.core.algorithm.termination.IterationWithoutImprovementTermination;
+import jsprit.core.problem.VehicleRoutingProblem;
+import jsprit.core.problem.constraint.AdditionalTransportationCosts;
+import jsprit.core.problem.constraint.ConstraintManager;
+import jsprit.core.problem.solution.SolutionCostCalculator;
+import jsprit.core.problem.solution.VehicleRoutingProblemSolution;
+import jsprit.core.problem.vehicle.InfiniteFleetManagerFactory;
+import jsprit.core.problem.vehicle.VehicleFleetManager;
+import jsprit.core.util.Solutions;
+import jsprit.instance.reader.SolomonReader;
+import jsprit.util.Examples;
+
+public class BuildAlgorithmFromScratchWithHardAndSoftConstraints {
+
+	/**
+	 * @param args
+	 */
+	public static void main(String[] args) {
+		/*
+		 * some preparation - create output folder
+		 */
+		Examples.createOutputFolder();
+		
+		/*
+		 * Build the problem.
+		 * 
+		 * But define a problem-builder first.
+		 */
+		VehicleRoutingProblem.Builder vrpBuilder = VehicleRoutingProblem.Builder.newInstance();
+		
+		/*
+		 * A solomonReader reads solomon-instance files, and stores the required information in the builder.
+		 */
+		new SolomonReader(vrpBuilder).read("input/C101_solomon.txt");
+		
+		/*
+		 * Finally, the problem can be built. By default, transportCosts are crowFlyDistances (as usually used for vrp-instances).
+		 */
+		VehicleRoutingProblem vrp = vrpBuilder.build();
+		
+		/*
+		 * Build algorithm
+		 */
+		VehicleRoutingAlgorithm vra = buildAlgorithmFromScratch(vrp);
+		
+		/*
+		 * search solution
+		 */
+		Collection<VehicleRoutingProblemSolution> solutions = vra.searchSolutions();
+		
+		/*
+		 * print result
+		 */
+		SolutionPrinter.print(Solutions.bestOf(solutions));
+
+	}
+
+	private static VehicleRoutingAlgorithm buildAlgorithmFromScratch(VehicleRoutingProblem vrp) {
+		
+		/*
+		 * manages route and activity states.
+		 */
+		StateManager stateManager = new StateManager(vrp);
+		/*
+		 * tells stateManager to update load states
+		 */
+		stateManager.updateLoadStates();
+		/*
+		 * tells stateManager to update time-window states
+		 */
+		stateManager.updateTimeWindowStates();
+		/*
+		 * stateManager.addStateUpdater(updater);
+		 * lets you register your own stateUpdater
+		 */
+		
+		/*
+		 * updates variable costs once a vehicleRoute has changed (by removing or adding a customer)
+		 */
+		stateManager.addStateUpdater(new UpdateVariableCosts(vrp.getActivityCosts(), vrp.getTransportCosts(), stateManager));
+		
+		/*
+		 * constructs a constraintManager that manages the various hardConstraints (and soon also softConstraints)
+		 */
+		ConstraintManager constraintManager = new ConstraintManager(vrp,stateManager);
+		/*
+		 * tells constraintManager to add timeWindowConstraints
+		 */
+		constraintManager.addTimeWindowConstraint();
+		/*
+		 * tells constraintManager to add loadConstraints
+		 */
+		constraintManager.addLoadConstraint();
+		/*
+		 * add an arbitrary number of hardConstraints by
+		 * constraintManager.addConstraint(...)
+		 */
+		constraintManager.addConstraint(new AdditionalTransportationCosts(vrp.getTransportCosts()));
+		
+		/*
+		 * define a fleetManager, here infinite vehicles can be used 
+		 */
+		VehicleFleetManager fleetManager = new InfiniteFleetManagerFactory(vrp.getVehicles()).createFleetManager();
+		
+		/*
+		 * define ruin-and-recreate strategies
+		 * 
+		 */
+		/*
+		 * first, define an insertion-strategy, i.e. bestInsertion
+		 */
+		BestInsertionBuilder iBuilder = new BestInsertionBuilder(vrp, fleetManager, stateManager, constraintManager);
+		/*
+		 * no need to set further options
+		 */
+		InsertionStrategy iStrategy = iBuilder.build();
+		
+		/*
+		 * second, define random-ruin that ruins 50-percent of the selected solution
+		 */
+		RuinStrategy randomRuin = new RandomRuinStrategyFactory(0.5).createStrategy(vrp);
+		
+		/*
+		 * third, define radial-ruin that ruins 30-percent of the selected solution
+		 * the second para defines the distance between two jobs.
+		 */
+		RuinStrategy radialRuin = new RadialRuinStrategyFactory(0.3, new AvgServiceAndShipmentDistance(vrp.getTransportCosts())).createStrategy(vrp);
+		
+		/*
+		 * now define a strategy
+		 */
+		/*
+		 * but before define how a generated solution is evaluated
+		 * here: the VariablePlusFixed.... comes out of the box and it does what its name suggests
+		 */
+		SolutionCostCalculator solutionCostCalculator = new VariablePlusFixedSolutionCostCalculatorFactory(stateManager).createCalculator();
+		
+		SearchStrategy firstStrategy = new SearchStrategy(new SelectBest(), new GreedyAcceptance(1), solutionCostCalculator);
+		firstStrategy.addModule(new RuinAndRecreateModule("randomRuinAndBestInsertion", iStrategy, randomRuin));
+		
+		SearchStrategy secondStrategy = new SearchStrategy(new SelectBest(), new GreedyAcceptance(1), solutionCostCalculator);
+		secondStrategy.addModule(new RuinAndRecreateModule("radialRuinAndBestInsertion", iStrategy, radialRuin));
+		
+		/*
+		 * put both strategies together, each with the prob of 0.5 to be selected
+		 */
+		SearchStrategyManager searchStrategyManager = new SearchStrategyManager();
+		searchStrategyManager.addStrategy(firstStrategy, 0.5);
+		searchStrategyManager.addStrategy(secondStrategy, 0.5);
+		
+		/*
+		 * construct the algorithm
+		 */
+		VehicleRoutingAlgorithm vra = new VehicleRoutingAlgorithm(vrp, searchStrategyManager);
+		//do not forgett to add the stateManager listening to the algorithm-stages
+		vra.addListener(stateManager);
+		//remove empty vehicles after insertion has finished
+		vra.addListener(new RemoveEmptyVehicles(fleetManager));
+		
+		/*
+		 * Do not forget to add an initial solution by vra.addInitialSolution(solution);
+		 * or
+		 */
+		vra.addInitialSolution(new InsertionInitialSolutionFactory(iStrategy, solutionCostCalculator).createSolution(vrp));
+		
+		/*
+		 * define the nIterations (by default nIteration=100)
+		 */
+		vra.setNuOfIterations(1000);
+		
+		/*
+		 * optionally define a premature termination criterion (by default: not criterion is set)
+		 */
+		vra.setPrematureAlgorithmTermination(new IterationWithoutImprovementTermination(100));
+		
+		return vra;
+	}
+
+}