1 files changed, 138 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/single/AbstractUniquenessEnforcerNode.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/single/AbstractUniquenessEnforcerNode.java
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index 00000000..e92ce63f
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+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/single/AbstractUniquenessEnforcerNode.java
@@ -0,0 +1,138 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2019, Tamas Szabo, itemis AG, Gabor Bergmann, 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.rete.single;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+
+import tools.refinery.viatra.runtime.matchers.tuple.Tuple;
+import tools.refinery.viatra.runtime.matchers.tuple.TupleMask;
+import tools.refinery.viatra.runtime.matchers.util.Direction;
+import tools.refinery.viatra.runtime.rete.index.ProjectionIndexer;
+import tools.refinery.viatra.runtime.rete.index.SpecializedProjectionIndexer.ListenerSubscription;
+import tools.refinery.viatra.runtime.rete.network.ReteContainer;
+import tools.refinery.viatra.runtime.rete.network.StandardNode;
+import tools.refinery.viatra.runtime.rete.network.Supplier;
+import tools.refinery.viatra.runtime.rete.network.Tunnel;
+import tools.refinery.viatra.runtime.rete.network.communication.Timestamp;
+import tools.refinery.viatra.runtime.rete.network.mailbox.Mailbox;
+import tools.refinery.viatra.runtime.rete.traceability.TraceInfo;
+import tools.refinery.viatra.runtime.rete.util.Options;
+
+/**
+ * Ensures that no identical copies get to the output. Only one replica of each pattern substitution may traverse this
+ * node. There are both timeless and timely implementations.
+ * 
+ * @author Gabor Bergmann
+ * @author Tamas Szabo
+ * @noinstantiate This class is not intended to be instantiated by clients.
+ * @noextend This class is not intended to be subclassed by clients.
+ * @since 2.2
+ */
+public abstract class AbstractUniquenessEnforcerNode extends StandardNode implements Tunnel {
+
+    protected final Collection<Supplier> parents;
+    protected ProjectionIndexer memoryNullIndexer;
+    protected ProjectionIndexer memoryIdentityIndexer;
+    protected final int tupleWidth;
+    // MUST BE INSTANTIATED IN THE CONCRETE SUBCLASSES AFTER ALL FIELDS ARE SET 
+    protected Mailbox mailbox;
+    protected final TupleMask nullMask;
+    protected final TupleMask identityMask;
+    protected final List<ListenerSubscription> specializedListeners;
+
+    public AbstractUniquenessEnforcerNode(final ReteContainer reteContainer, final int tupleWidth) {
+        super(reteContainer);
+        this.parents = new ArrayList<Supplier>();
+        this.specializedListeners = new ArrayList<ListenerSubscription>();
+        this.tupleWidth = tupleWidth;
+        this.nullMask = TupleMask.linear(0, tupleWidth);
+        this.identityMask = TupleMask.identity(tupleWidth);
+    }
+
+    protected abstract Mailbox instantiateMailbox();
+
+    @Override
+    public Mailbox getMailbox() {
+        return this.mailbox;
+    }
+    
+    /**
+     * @since 2.8
+     */
+    public abstract Set<Tuple> getTuples();
+
+    /**
+     * @since 2.4
+     */
+    protected void propagate(final Direction direction, final Tuple update, final Timestamp timestamp) {
+        // See Bug 518434
+        // trivial (non-active) indexers must be updated before other listeners
+        // so that if they are joined against each other, trivial indexers lookups
+        // will be consistent with their notifications;
+        // also, their subscriptions must share a single order
+        for (final ListenerSubscription subscription : specializedListeners) {
+            subscription.propagate(direction, update, timestamp);
+        }
+        propagateUpdate(direction, update, timestamp);
+    }
+
+    @Override
+    public ProjectionIndexer constructIndex(final TupleMask mask, final TraceInfo... traces) {
+        if (Options.employTrivialIndexers) {
+            if (nullMask.equals(mask)) {
+                final ProjectionIndexer indexer = getNullIndexer();
+                for (final TraceInfo traceInfo : traces) {
+                    indexer.assignTraceInfo(traceInfo);
+                }
+                return indexer;
+            }
+            if (identityMask.equals(mask)) {
+                final ProjectionIndexer indexer = getIdentityIndexer();
+                for (final TraceInfo traceInfo : traces) {
+                    indexer.assignTraceInfo(traceInfo);
+                }
+                return indexer;
+            }
+        }
+        return super.constructIndex(mask, traces);
+    }
+
+    public abstract ProjectionIndexer getNullIndexer();
+
+    public abstract ProjectionIndexer getIdentityIndexer();
+
+    @Override
+    public void appendParent(final Supplier supplier) {
+        parents.add(supplier);
+    }
+
+    @Override
+    public void removeParent(final Supplier supplier) {
+        parents.remove(supplier);
+    }
+
+    @Override
+    public Collection<Supplier> getParents() {
+        return parents;
+    }
+
+    @Override
+    public void assignTraceInfo(final TraceInfo traceInfo) {
+        super.assignTraceInfo(traceInfo);
+        if (traceInfo.propagateFromStandardNodeToSupplierParent()) {
+            for (final Supplier parent : parents) {
+                parent.acceptPropagatedTraceInfo(traceInfo);
+            }
+        }
+    }
+
+}
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