1 files changed, 106 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/operations/extend/AggregatorExtend.java b/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/operations/extend/AggregatorExtend.java
new file mode 100644
index 00000000..c2e75b7a
--- /dev/null
+++ b/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/operations/extend/AggregatorExtend.java
@@ -0,0 +1,106 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2016, Grill Balázs, IncQuery Labs Ltd.
+ * 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.operations.extend;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Stream;
+
+import tools.refinery.viatra.runtime.localsearch.MatchingFrame;
+import tools.refinery.viatra.runtime.localsearch.matcher.ISearchContext;
+import tools.refinery.viatra.runtime.localsearch.operations.IPatternMatcherOperation;
+import tools.refinery.viatra.runtime.localsearch.operations.ISearchOperation;
+import tools.refinery.viatra.runtime.localsearch.operations.util.CallInformation;
+import tools.refinery.viatra.runtime.matchers.backend.IQueryResultProvider;
+import tools.refinery.viatra.runtime.matchers.psystem.aggregations.IMultisetAggregationOperator;
+import tools.refinery.viatra.runtime.matchers.psystem.basicdeferred.AggregatorConstraint;
+import tools.refinery.viatra.runtime.matchers.tuple.VolatileModifiableMaskedTuple;
+
+/**
+ * Calculates the aggregated value of a column based on the given {@link AggregatorConstraint}
+ * 
+ * @author Balázs Grill
+ * @since 1.4
+ */
+public class AggregatorExtend  implements ISearchOperation, IPatternMatcherOperation{
+
+    private class Executor extends SingleValueExtendOperationExecutor<Object> {
+
+        private final VolatileModifiableMaskedTuple maskedTuple;
+        private IQueryResultProvider matcher;
+        
+        public Executor(int position) {
+            super(position);
+            this.maskedTuple = new VolatileModifiableMaskedTuple(information.getThinFrameMask());
+        }
+        
+        @Override
+        public Iterator<?> getIterator(MatchingFrame frame, ISearchContext context) {
+            maskedTuple.updateTuple(frame);
+            matcher = context.getMatcher(information.getCallWithAdornment());
+            Object aggregate = aggregate(aggregator.getAggregator().getOperator(), aggregator.getAggregatedColumn());
+            return aggregate == null ? Collections.emptyIterator() : Collections.singletonList(aggregate).iterator();
+            
+        }
+        
+        @SuppressWarnings("unchecked")
+        private <Domain, Accumulator, AggregateResult> AggregateResult aggregate(
+                IMultisetAggregationOperator<Domain, Accumulator, AggregateResult> operator, int aggregatedColumn) {
+            final Stream<Domain> valueStream = matcher.getAllMatches(information.getParameterMask(), maskedTuple)
+                    .map(match -> (Domain) match.get(aggregatedColumn));
+            return operator.aggregateStream(valueStream);
+        }
+        
+        @Override
+        public ISearchOperation getOperation() {
+            return AggregatorExtend.this;
+        }
+    }
+    
+    private final AggregatorConstraint aggregator;
+    private final CallInformation information; 
+    private final int position;
+    
+    /**
+     * @since 1.7
+     */
+    public AggregatorExtend(CallInformation information, AggregatorConstraint aggregator, int position) {
+        this.aggregator = aggregator;
+        this.information = information;
+        this.position = position;
+    }
+    
+    @Override
+    public ISearchOperationExecutor createExecutor() {
+        return new Executor(position);
+    }
+
+    @Override
+    public List<Integer> getVariablePositions() {
+        return Arrays.asList(position);
+    }
+    
+    @Override
+    public String toString() {
+        return toString(Object::toString);
+    }
+    
+    @Override
+    public String toString(Function<Integer, String> variableMapping) {
+        return "extend    -"+variableMapping.apply(position)+" = " + aggregator.getAggregator().getOperator().getName()+" find " + information.toString(variableMapping);
+    }
+    
+    @Override
+    public CallInformation getCallInformation() {
+        return information;
+    }
+}