fix: Ruin&Recreate score corruption and multi-threaded fixes (#1320)

Fixes TimefoldAI/timefold-employee-scheduling#305

Author: zepfred

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/DefaultConstructionHeuristicPhase.java

@@ -101,7 +101,7 @@ protected ConstructionHeuristicPhaseScope<Solution_> buildPhaseScope(SolverScope
         return new ConstructionHeuristicPhaseScope<>(solverScope, phaseIndex);
     }
 
-    private void doStep(ConstructionHeuristicStepScope<Solution_> stepScope) {
+    protected void doStep(ConstructionHeuristicStepScope<Solution_> stepScope) {
         var step = stepScope.getStep();
         step.execute(stepScope.getMoveDirector());
         predictWorkingStepScore(stepScope, step);

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/AbstractEntityPlacer.java

@@ -1,5 +1,6 @@
 package ai.timefold.solver.core.impl.constructionheuristic.placer;
 
+import ai.timefold.solver.core.impl.heuristic.HeuristicConfigPolicy;
 import ai.timefold.solver.core.impl.phase.event.PhaseLifecycleSupport;
 import ai.timefold.solver.core.impl.phase.scope.AbstractPhaseScope;
 import ai.timefold.solver.core.impl.phase.scope.AbstractStepScope;
@@ -17,8 +18,24 @@ public abstract class AbstractEntityPlacer<Solution_> implements EntityPlacer<So
 
     protected final transient Logger logger = LoggerFactory.getLogger(getClass());
 
+    protected final EntityPlacerFactory<Solution_> factory;
+    protected final HeuristicConfigPolicy<Solution_> configPolicy;
+
     protected PhaseLifecycleSupport<Solution_> phaseLifecycleSupport = new PhaseLifecycleSupport<>();
 
+    AbstractEntityPlacer(EntityPlacerFactory<Solution_> factory, HeuristicConfigPolicy<Solution_> configPolicy) {
+        this.factory = factory;
+        this.configPolicy = configPolicy;
+    }
+
+    @Override
+    public EntityPlacer<Solution_> copy() {
+        if (factory == null || configPolicy == null) {
+            throw new IllegalStateException("The entity placer cannot be copied.");
+        }
+        return factory.buildEntityPlacer(configPolicy.copyConfigPolicy());
+    }
+
     @Override
     public void solvingStarted(SolverScope<Solution_> solverScope) {
         phaseLifecycleSupport.fireSolvingStarted(solverScope);

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/EntityPlacer.java

@@ -7,4 +7,5 @@ public interface EntityPlacer<Solution_> extends Iterable<Placement<Solution_>>,
 
     EntityPlacer<Solution_> rebuildWithFilter(SelectionFilter<Solution_, Object> filter);
 
+    EntityPlacer<Solution_> copy();
 }

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/PooledEntityPlacer.java

@@ -2,6 +2,7 @@
 
 import java.util.Iterator;
 
+import ai.timefold.solver.core.impl.heuristic.HeuristicConfigPolicy;
 import ai.timefold.solver.core.impl.heuristic.move.Move;
 import ai.timefold.solver.core.impl.heuristic.selector.common.decorator.SelectionFilter;
 import ai.timefold.solver.core.impl.heuristic.selector.common.iterator.UpcomingSelectionIterator;
@@ -13,7 +14,9 @@ public class PooledEntityPlacer<Solution_> extends AbstractEntityPlacer<Solution
 
     protected final MoveSelector<Solution_> moveSelector;
 
-    public PooledEntityPlacer(MoveSelector<Solution_> moveSelector) {
+    public PooledEntityPlacer(EntityPlacerFactory<Solution_> factory, HeuristicConfigPolicy<Solution_> configPolicy,
+            MoveSelector<Solution_> moveSelector) {
+        super(factory, configPolicy);
         this.moveSelector = moveSelector;
         phaseLifecycleSupport.addEventListener(moveSelector);
     }
@@ -25,7 +28,7 @@ public Iterator<Placement<Solution_>> iterator() {
 
     @Override
     public EntityPlacer<Solution_> rebuildWithFilter(SelectionFilter<Solution_, Object> filter) {
-        return new PooledEntityPlacer<>(FilteringMoveSelector.of(moveSelector, filter::accept));
+        return new PooledEntityPlacer<>(factory, configPolicy, FilteringMoveSelector.of(moveSelector, filter::accept));
     }
 
     private class PooledEntityPlacingIterator extends UpcomingSelectionIterator<Placement<Solution_>> {

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/PooledEntityPlacerFactory.java

@@ -69,7 +69,7 @@ public PooledEntityPlacer<Solution_> buildEntityPlacer(HeuristicConfigPolicy<Sol
 
         MoveSelector<Solution_> moveSelector = MoveSelectorFactory.<Solution_> create(moveSelectorConfig_)
                 .buildMoveSelector(configPolicy, SelectionCacheType.JUST_IN_TIME, SelectionOrder.ORIGINAL, false);
-        return new PooledEntityPlacer<>(moveSelector);
+        return new PooledEntityPlacer<>(this, configPolicy, moveSelector);
     }
 
     private MoveSelectorConfig buildMoveSelectorConfig(HeuristicConfigPolicy<Solution_> configPolicy) {

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/QueuedEntityPlacer.java

@@ -4,6 +4,7 @@
 import java.util.Iterator;
 import java.util.List;
 
+import ai.timefold.solver.core.impl.heuristic.HeuristicConfigPolicy;
 import ai.timefold.solver.core.impl.heuristic.move.Move;
 import ai.timefold.solver.core.impl.heuristic.selector.common.decorator.SelectionFilter;
 import ai.timefold.solver.core.impl.heuristic.selector.common.iterator.UpcomingSelectionIterator;
@@ -17,7 +18,9 @@ public class QueuedEntityPlacer<Solution_> extends AbstractEntityPlacer<Solution
     protected final EntitySelector<Solution_> entitySelector;
     protected final List<MoveSelector<Solution_>> moveSelectorList;
 
-    public QueuedEntityPlacer(EntitySelector<Solution_> entitySelector, List<MoveSelector<Solution_>> moveSelectorList) {
+    public QueuedEntityPlacer(EntityPlacerFactory<Solution_> factory, HeuristicConfigPolicy<Solution_> configPolicy,
+            EntitySelector<Solution_> entitySelector, List<MoveSelector<Solution_>> moveSelectorList) {
+        super(factory, configPolicy);
         this.entitySelector = entitySelector;
         this.moveSelectorList = moveSelectorList;
         phaseLifecycleSupport.addEventListener(entitySelector);
@@ -33,7 +36,8 @@ public Iterator<Placement<Solution_>> iterator() {
 
     @Override
     public EntityPlacer<Solution_> rebuildWithFilter(SelectionFilter<Solution_, Object> filter) {
-        return new QueuedEntityPlacer<>(FilteringEntitySelector.of(entitySelector, filter), moveSelectorList);
+        return new QueuedEntityPlacer<>(factory, configPolicy, FilteringEntitySelector.of(entitySelector, filter),
+                moveSelectorList);
     }
 
     private class QueuedEntityPlacingIterator extends UpcomingSelectionIterator<Placement<Solution_>> {

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/QueuedEntityPlacerFactory.java

@@ -76,7 +76,7 @@ public QueuedEntityPlacer<Solution_> buildEntityPlacer(HeuristicConfigPolicy<Sol
                     .buildMoveSelector(configPolicy, SelectionCacheType.JUST_IN_TIME, SelectionOrder.ORIGINAL, false);
             moveSelectorList.add(moveSelector);
         }
-        return new QueuedEntityPlacer<>(entitySelector, moveSelectorList);
+        return new QueuedEntityPlacer<>(this, configPolicy, entitySelector, moveSelectorList);
     }
 
     @SuppressWarnings("rawtypes")

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/QueuedValuePlacer.java

@@ -3,6 +3,7 @@
 import java.util.Collections;
 import java.util.Iterator;
 
+import ai.timefold.solver.core.impl.heuristic.HeuristicConfigPolicy;
 import ai.timefold.solver.core.impl.heuristic.selector.common.decorator.SelectionFilter;
 import ai.timefold.solver.core.impl.heuristic.selector.common.iterator.UpcomingSelectionIterator;
 import ai.timefold.solver.core.impl.heuristic.selector.move.MoveSelector;
@@ -16,8 +17,9 @@ public class QueuedValuePlacer<Solution_> extends AbstractEntityPlacer<Solution_
     protected final EntityIndependentValueSelector<Solution_> valueSelector;
     protected final MoveSelector<Solution_> moveSelector;
 
-    public QueuedValuePlacer(EntityIndependentValueSelector<Solution_> valueSelector,
-            MoveSelector<Solution_> moveSelector) {
+    public QueuedValuePlacer(EntityPlacerFactory<Solution_> factory, HeuristicConfigPolicy<Solution_> configPolicy,
+            EntityIndependentValueSelector<Solution_> valueSelector, MoveSelector<Solution_> moveSelector) {
+        super(factory, configPolicy);
         this.valueSelector = valueSelector;
         this.moveSelector = moveSelector;
         phaseLifecycleSupport.addEventListener(valueSelector);
@@ -59,7 +61,7 @@ protected Placement<Solution_> createUpcomingSelection() {
 
     @Override
     public EntityPlacer<Solution_> rebuildWithFilter(SelectionFilter<Solution_, Object> filter) {
-        return new QueuedValuePlacer<>(
+        return new QueuedValuePlacer<>(factory, configPolicy,
                 (EntityIndependentFilteringValueSelector<Solution_>) FilteringValueSelector.of(valueSelector, filter),
                 moveSelector);
     }

core/src/main/java/ai/timefold/solver/core/impl/constructionheuristic/placer/QueuedValuePlacerFactory.java

@@ -55,7 +55,8 @@ public QueuedValuePlacer<Solution_> buildEntityPlacer(HeuristicConfigPolicy<Solu
                     + " Check your @" + ValueRangeProvider.class.getSimpleName() + " annotations.");
 
         }
-        return new QueuedValuePlacer<>((EntityIndependentValueSelector<Solution_>) valueSelector, moveSelector);
+        return new QueuedValuePlacer<>(this, configPolicy, (EntityIndependentValueSelector<Solution_>) valueSelector,
+                moveSelector);
     }
 
     private ValueSelectorConfig buildValueSelectorConfig(HeuristicConfigPolicy<Solution_> configPolicy,

core/src/main/java/ai/timefold/solver/core/impl/heuristic/HeuristicConfigPolicy.java

@@ -147,6 +147,16 @@ public Builder<Solution_> cloneBuilder() {
                 .withLogIndentation(logIndentation);
     }
 
+    public HeuristicConfigPolicy<Solution_> copyConfigPolicy() {
+        return cloneBuilder()
+                .withEntitySorterManner(entitySorterManner)
+                .withValueSorterManner(valueSorterManner)
+                .withReinitializeVariableFilterEnabled(reinitializeVariableFilterEnabled)
+                .withInitializedChainedValueFilterEnabled(initializedChainedValueFilterEnabled)
+                .withUnassignedValuesAllowed(unassignedValuesAllowed)
+                .build();
+    }
+
     public HeuristicConfigPolicy<Solution_> createPhaseConfigPolicy() {
         return cloneBuilder().build();
     }