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diff --git a/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/matcher/LocalSearchMatcher.java b/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/matcher/LocalSearchMatcher.java
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+++ b/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/matcher/LocalSearchMatcher.java
@@ -0,0 +1,301 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2013, Zoltan Ujhelyi, Marton Bur, Istvan Rath and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.localsearch.matcher;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Set;
+import java.util.Spliterator;
+import java.util.Spliterators;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
+
+import tools.refinery.viatra.runtime.localsearch.MatchingFrame;
+import tools.refinery.viatra.runtime.localsearch.plan.IPlanDescriptor;
+import tools.refinery.viatra.runtime.localsearch.plan.SearchPlan;
+import tools.refinery.viatra.runtime.localsearch.plan.SearchPlanExecutor;
+import tools.refinery.viatra.runtime.matchers.psystem.queries.PQuery;
+import tools.refinery.viatra.runtime.matchers.tuple.ITuple;
+import tools.refinery.viatra.runtime.matchers.tuple.Tuple;
+import tools.refinery.viatra.runtime.matchers.tuple.TupleMask;
+import tools.refinery.viatra.runtime.matchers.tuple.VolatileModifiableMaskedTuple;
+import tools.refinery.viatra.runtime.matchers.util.Preconditions;
+
+/**
+ * @author Zoltan Ujhelyi
+ * @noinstantiate This class is not intended to be instantiated by clients.
+ */
+public final class LocalSearchMatcher implements ILocalSearchAdaptable {
+
+    private final List<SearchPlanExecutor> plan;
+    private final IPlanDescriptor planDescriptor;
+    private final List<ILocalSearchAdapter> adapters;
+
+    /**
+     * @since 2.0
+     */
+    public List<SearchPlanExecutor> getPlan() {
+        return plan;
+    }
+    
+    @Override
+    public List<ILocalSearchAdapter> getAdapters() {
+        return new ArrayList<>(adapters);
+    }
+    
+    private abstract class PlanExecutionIterator implements Iterator<Tuple> {
+
+        protected final Iterator<SearchPlanExecutor> planIterator;
+        
+        protected SearchPlanExecutor currentPlan;
+        protected MatchingFrame frame;
+        protected final Set<ITuple> matchSet;
+        protected VolatileModifiableMaskedTuple parametersOfFrameView; 
+        private boolean isNextMatchCalculated;
+        
+        public PlanExecutionIterator(final Iterator<SearchPlanExecutor> planIterator) {
+            this.planIterator = planIterator;
+            isNextMatchCalculated = false;
+            matchSet = new HashSet<>();
+        }
+
+        protected boolean selectNextPlan() {
+            if(currentPlan != null) {
+                currentPlan.removeAdapters(adapters);
+            }
+            boolean validPlanSelected = false;
+            
+            SearchPlanExecutor nextPlan = null;
+            
+            while (!validPlanSelected && planIterator.hasNext()) {
+                nextPlan = planIterator.next();
+                nextPlan.addAdapters(adapters);
+                nextPlan.resetPlan();
+                
+                validPlanSelected = initializeMatchingFrame(nextPlan);
+            }
+            
+            if (validPlanSelected) {
+                for (ILocalSearchAdapter adapter : adapters) {
+                    adapter.planChanged(Optional.ofNullable(currentPlan).map(SearchPlanExecutor::getSearchPlan),
+                            Optional.ofNullable(nextPlan).map(SearchPlanExecutor::getSearchPlan));
+                }
+                currentPlan = nextPlan;
+                return true;
+            } else {
+                currentPlan = null;
+                return false;
+            }
+        }
+
+        protected abstract boolean initializeMatchingFrame(SearchPlanExecutor nextPlan);
+
+        private boolean findNextNewMatchInCurrentPlan() {
+            boolean foundMatch = currentPlan.execute(frame);
+            while (foundMatch && matchSet.contains(parametersOfFrameView)) {
+                for (ILocalSearchAdapter adapter : adapters) {
+                    adapter.duplicateMatchFound(frame);
+                }
+                foundMatch = currentPlan.execute(frame);
+            }
+            return foundMatch;
+        }
+        
+        @Override
+        public boolean hasNext() {
+            if (isNextMatchCalculated) {
+                return true;
+            }
+            if (currentPlan == null) {
+                return false;
+            }
+            boolean foundMatch = findNextNewMatchInCurrentPlan();
+            
+            while (!foundMatch && planIterator.hasNext()) {
+                foundMatch = selectNextPlan() && findNextNewMatchInCurrentPlan();
+            }
+            if (!foundMatch) {
+                for (ILocalSearchAdapter adapter : adapters) {
+                    adapter.noMoreMatchesAvailable(LocalSearchMatcher.this);
+                }
+            }
+            isNextMatchCalculated = foundMatch;
+            return foundMatch;
+        }
+
+        @Override
+        public Tuple next() {
+            if (!hasNext()) {
+                throw new NoSuchElementException("No more matches available.");
+            }
+            isNextMatchCalculated = false;
+            final Tuple match = parametersOfFrameView.toImmutable();
+            matchSet.add(match);
+            return match;
+        }
+    }
+
+    private class PlanExecutionIteratorWithArrayParameters extends PlanExecutionIterator {
+        
+        private final Object[] parameterValues;
+        
+        public PlanExecutionIteratorWithArrayParameters(Iterator<SearchPlanExecutor> planIterator, final Object[] parameterValues) {
+            super(planIterator);
+            this.parameterValues = parameterValues;
+            selectNextPlan();
+        }
+        
+        protected boolean initializeMatchingFrame(SearchPlanExecutor nextPlan) {
+            frame = new MatchingFrame(nextPlan.getVariableMapping().size());
+            parametersOfFrameView = new VolatileModifiableMaskedTuple(frame, nextPlan.getParameterMask());
+            for (int i = 0; i < parameterValues.length; i++) {
+                Object valueToSet = parameterValues[i];
+                if (valueToSet != null) {
+                    Object oldValue = parametersOfFrameView.get(i);
+                    if (oldValue == null) {
+                        parametersOfFrameView.set(i, valueToSet);
+                    } else if (!Objects.equals(valueToSet, oldValue)) {
+                        // Initial value setting resulted in contradictory values. This can happen because two parameter
+                        // variables have been unified but the call provides different values for the parameters.
+                        return false;
+                    }
+                    // If oldValue is not null but equal to newValue, the setting can be ignored
+                }
+            }
+            
+            return true;
+        }
+    }
+    private class PlanExecutionIteratorWithTupleParameters extends PlanExecutionIterator {
+        
+        private final ITuple parameterValues;
+        private final TupleMask parameterSeedMask;
+        
+        public PlanExecutionIteratorWithTupleParameters(Iterator<SearchPlanExecutor> planIterator, final TupleMask parameterSeedMask, final ITuple parameterValues) {
+            super(planIterator);
+            this.parameterSeedMask = parameterSeedMask;
+            this.parameterValues = parameterValues;
+            selectNextPlan();
+        }
+        
+        protected boolean initializeMatchingFrame(SearchPlanExecutor nextPlan) {
+            frame = new MatchingFrame(nextPlan.getVariableMapping().size());
+            parametersOfFrameView = new VolatileModifiableMaskedTuple(frame, nextPlan.getParameterMask());
+            for (int i = 0; i < parameterSeedMask.getSize(); i++) {
+                int index = parameterSeedMask.indices[i];
+                Object valueToSet = parameterValues.get(i);
+                if (valueToSet != null) {
+                    Object oldValue = parametersOfFrameView.get(index);
+                    if (oldValue == null) {
+                        parametersOfFrameView.set(index, valueToSet);
+                    } else if (!Objects.equals(valueToSet, oldValue)) {
+                        // Initial value setting resulted in contradictory values. This can happen because two parameter
+                        // variables have been unified but the call provides different values for the parameters.
+                        return false;
+                    }
+                    // If oldValue is not null but equal to newValue, the setting can be ignored
+                }
+            }
+            
+            return true;
+        }
+    }
+
+    /**
+     * @since 2.0
+     */
+    public LocalSearchMatcher(ISearchContext searchContext, IPlanDescriptor planDescriptor, List<SearchPlan> plan) {
+        Preconditions.checkArgument(planDescriptor != null, "Cannot initialize matcher with null query.");
+        this.planDescriptor = planDescriptor;
+        this.plan = plan.stream().map(p -> new SearchPlanExecutor(p, searchContext)).collect(Collectors.toList());
+        this.adapters = new LinkedList<>();
+    }
+    
+    @Override
+    public void addAdapter(ILocalSearchAdapter adapter) {
+        this.adapters.add(adapter);
+        adapter.adapterRegistered(this);
+    }
+
+    @Override
+    public void removeAdapter(ILocalSearchAdapter adapter) {
+        this.adapters.remove(adapter);
+        adapter.adapterUnregistered(this);
+    }
+    
+    @Override
+    public void addAdapters(List<ILocalSearchAdapter> adapters) {
+        this.adapters.addAll(adapters);
+        for (ILocalSearchAdapter adapter : adapters) {
+            adapter.adapterRegistered(this);
+        }
+    }
+
+    @Override
+    public void removeAdapters(List<ILocalSearchAdapter> adapters) {
+        this.adapters.removeAll(adapters);
+        for (ILocalSearchAdapter adapter : adapters) {
+            adapter.adapterUnregistered(this);
+        }
+    }
+    
+    public int getParameterCount() {
+        return planDescriptor.getQuery().getParameters().size();
+    }
+
+    private void matchingStarted() {
+        for (ILocalSearchAdapter adapter : adapters) {
+            adapter.patternMatchingStarted(this);
+        }
+    }
+
+    /**
+     * @since 2.0
+     */
+    public Stream<Tuple> streamMatches(final Object[] parameterValues) {
+        matchingStarted();
+        PlanExecutionIterator it = new PlanExecutionIteratorWithArrayParameters(plan.iterator(), parameterValues);
+        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(it,
+                Spliterator.IMMUTABLE | Spliterator.NONNULL | Spliterator.DISTINCT), false);
+    }
+    
+    /**
+     * @since 2.0
+     */
+    public Stream<Tuple> streamMatches(TupleMask parameterSeedMask, final ITuple parameterValues) {
+        matchingStarted();
+        PlanExecutionIterator it = new PlanExecutionIteratorWithTupleParameters(
+                plan.iterator(), parameterSeedMask, parameterValues);
+        return StreamSupport.stream(Spliterators.spliteratorUnknownSize(it,
+                Spliterator.IMMUTABLE | Spliterator.NONNULL | Spliterator.DISTINCT), false);
+    }
+    
+    /**
+     * Returns the query specification this matcher used as source for the implementation
+     * @return never null
+     */
+    public PQuery getQuerySpecification() {
+        return planDescriptor.getQuery();
+    }
+    
+    
+    /**
+     * @since 1.5
+     */
+    public IPlanDescriptor getPlanDescriptor() {
+        return planDescriptor;
+    }
+}