make no. unassigned jobs configurable - related to #431

jsprit-core/src/main/java/com/graphhopper/jsprit/core/algorithm/module/RuinAndRecreateModule.java

@@ -26,9 +26,7 @@ import com.graphhopper.jsprit.core.algorithm.ruin.listener.RuinListener;
 import com.graphhopper.jsprit.core.problem.job.Job;
 import com.graphhopper.jsprit.core.problem.solution.VehicleRoutingProblemSolution;
 
-import java.util.Collection;
+import java.util.*;
-import java.util.HashSet;
-import java.util.Set;
 
 
 public class RuinAndRecreateModule implements SearchStrategyModule {
@@ -39,6 +37,12 @@ public class RuinAndRecreateModule implements SearchStrategyModule {
 
     private String moduleName;
 
+    private Random random = new Random(4711);
+
+    private int minUnassignedJobsToBeReinserted = Integer.MAX_VALUE;
+
+    private double proportionOfUnassignedJobsToBeReinserted = 1d;
+
     public RuinAndRecreateModule(String moduleName, InsertionStrategy insertion, RuinStrategy ruin) {
         super();
         this.insertion = insertion;
@@ -46,16 +50,58 @@ public class RuinAndRecreateModule implements SearchStrategyModule {
         this.moduleName = moduleName;
     }
 
+    /**
+     * To make overall results reproducible, make sure this class is provided with the "global" random number generator.
+     *
+     * @param random
+     */
+    public void setRandom(Random random) {
+        this.random = random;
+    }
+
+    /**
+     * Minimum number of unassigned jobs that is reinserted in each iteration.
+     *
+     * @param minUnassignedJobsToBeReinserted
+     */
+    public void setMinUnassignedJobsToBeReinserted(int minUnassignedJobsToBeReinserted) {
+        this.minUnassignedJobsToBeReinserted = minUnassignedJobsToBeReinserted;
+    }
+
+    /**
+     * Proportion of unassigned jobs that is reinserted in each iteration.
+     *
+     * @param proportionOfUnassignedJobsToBeReinserted
+     */
+    public void setProportionOfUnassignedJobsToBeReinserted(double proportionOfUnassignedJobsToBeReinserted) {
+        this.proportionOfUnassignedJobsToBeReinserted = proportionOfUnassignedJobsToBeReinserted;
+    }
+
     @Override
-    public VehicleRoutingProblemSolution runAndGetSolution(VehicleRoutingProblemSolution vrpSolution) {
+    public VehicleRoutingProblemSolution runAndGetSolution(VehicleRoutingProblemSolution previousVrpSolution) {
-        Collection<Job> ruinedJobs = ruin.ruin(vrpSolution.getRoutes());
+        Collection<Job> ruinedJobs = ruin.ruin(previousVrpSolution.getRoutes());
-        Set<Job> ruinedJobSet = new HashSet<Job>();
+        Set<Job> ruinedJobSet = new HashSet<>();
         ruinedJobSet.addAll(ruinedJobs);
-        ruinedJobSet.addAll(vrpSolution.getUnassignedJobs());
+        List<Job> stillUnassignedInThisIteration = new ArrayList<>();
-        Collection<Job> unassignedJobs = insertion.insertJobs(vrpSolution.getRoutes(), ruinedJobSet);
+        if (previousVrpSolution.getUnassignedJobs().size() < minUnassignedJobsToBeReinserted) {
-        vrpSolution.getUnassignedJobs().clear();
+            ruinedJobSet.addAll(previousVrpSolution.getUnassignedJobs());
-        vrpSolution.getUnassignedJobs().addAll(unassignedJobs);
+        } else {
-        return vrpSolution;
+            int noUnassignedToBeInserted = Math.max(minUnassignedJobsToBeReinserted, (int) (previousVrpSolution.getUnassignedJobs().size() * proportionOfUnassignedJobsToBeReinserted));
+            List<Job> jobList = new ArrayList<>(previousVrpSolution.getUnassignedJobs());
+            Collections.shuffle(jobList, random);
+            for (int i = 0; i < noUnassignedToBeInserted; i++) {
+                ruinedJobSet.add(jobList.get(i));
+            }
+            for (int i = noUnassignedToBeInserted; i < jobList.size(); i++) {
+                stillUnassignedInThisIteration.add(jobList.get(i));
+            }
+        }
+        Collection<Job> unassignedJobs = insertion.insertJobs(previousVrpSolution.getRoutes(), ruinedJobSet);
+        previousVrpSolution.getUnassignedJobs().clear();
+        previousVrpSolution.getUnassignedJobs().addAll(unassignedJobs);
+        previousVrpSolution.getUnassignedJobs().addAll(stillUnassignedInThisIteration);
+        VehicleRoutingProblemSolution newSolution = previousVrpSolution;
+        return newSolution;
 
     }
 

jsprit-core/src/test/java/com/graphhopper/jsprit/core/algorithm/module/RuinAndRecreateModuleTest.java

@@ -0,0 +1,85 @@
+/*
+ * Licensed to GraphHopper GmbH under one or more contributor
+ * license agreements. See the NOTICE file distributed with this work for
+ * additional information regarding copyright ownership.
+ *
+ * GraphHopper GmbH licenses this file to you under the Apache License,
+ * Version 2.0 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.graphhopper.jsprit.core.algorithm.module;
+
+import com.graphhopper.jsprit.core.algorithm.recreate.InsertionStrategy;
+import com.graphhopper.jsprit.core.algorithm.ruin.RuinStrategy;
+import com.graphhopper.jsprit.core.problem.job.Job;
+import com.graphhopper.jsprit.core.problem.solution.VehicleRoutingProblemSolution;
+import com.graphhopper.jsprit.core.problem.solution.route.VehicleRoute;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import static org.mockito.Mockito.mock;
+
+public class RuinAndRecreateModuleTest {
+
+    @Test
+    public void initialNumOfUnassignedShouldWorkCorrectly() {
+        InsertionStrategy insertionStrategy = mock(InsertionStrategy.class);
+        RuinStrategy ruinStrategy = mock(RuinStrategy.class);
+        RuinAndRecreateModule module = new RuinAndRecreateModule("name", insertionStrategy, ruinStrategy);
+        Collection<VehicleRoute> routes = new ArrayList<>();
+        List<Job> unassigned = new ArrayList<>();
+        for (int i = 0; i < 20; i++) {
+            unassigned.add(mock(Job.class));
+        }
+        VehicleRoutingProblemSolution previousSolution = new VehicleRoutingProblemSolution(routes, unassigned, 0);
+        VehicleRoutingProblemSolution newSolution = module.runAndGetSolution(previousSolution);
+        Assert.assertEquals(0, newSolution.getUnassignedJobs().size());
+    }
+
+    @Test
+    public void proportionOfUnassignedShouldWorkCorrectly() {
+        InsertionStrategy insertionStrategy = mock(InsertionStrategy.class);
+        RuinStrategy ruinStrategy = mock(RuinStrategy.class);
+        RuinAndRecreateModule module = new RuinAndRecreateModule("name", insertionStrategy, ruinStrategy);
+        module.setMinUnassignedJobsToBeReinserted(5);
+        module.setProportionOfUnassignedJobsToBeReinserted(0.01);
+        Collection<VehicleRoute> routes = new ArrayList<>();
+        List<Job> unassigned = new ArrayList<>();
+        for (int i = 0; i < 20; i++) {
+            unassigned.add(mock(Job.class));
+        }
+        VehicleRoutingProblemSolution previousSolution = new VehicleRoutingProblemSolution(routes, unassigned, 0);
+        VehicleRoutingProblemSolution newSolution = module.runAndGetSolution(previousSolution);
+        Assert.assertEquals(15, newSolution.getUnassignedJobs().size());
+    }
+
+    @Test
+    public void proportionOfUnassignedShouldWorkCorrectly2() {
+        InsertionStrategy insertionStrategy = mock(InsertionStrategy.class);
+        RuinStrategy ruinStrategy = mock(RuinStrategy.class);
+        RuinAndRecreateModule module = new RuinAndRecreateModule("name", insertionStrategy, ruinStrategy);
+        module.setMinUnassignedJobsToBeReinserted(5);
+        module.setProportionOfUnassignedJobsToBeReinserted(0.5);
+        Collection<VehicleRoute> routes = new ArrayList<>();
+        List<Job> unassigned = new ArrayList<>();
+        for (int i = 0; i < 20; i++) {
+            unassigned.add(mock(Job.class));
+        }
+        VehicleRoutingProblemSolution previousSolution = new VehicleRoutingProblemSolution(routes, unassigned, 0);
+        VehicleRoutingProblemSolution newSolution = module.runAndGetSolution(previousSolution);
+        Assert.assertEquals(10, newSolution.getUnassignedJobs().size());
+    }
+}