1 files changed, 41 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/IndexerListener.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/IndexerListener.java
new file mode 100644
index 00000000..f52b6a06
--- /dev/null
+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/index/IndexerListener.java
@@ -0,0 +1,41 @@
+/*******************************************************************************
+ * Copyright (c) 2004-2008 Gabor Bergmann 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.rete.index;
+
+import tools.refinery.viatra.runtime.matchers.tuple.Tuple;
+import tools.refinery.viatra.runtime.matchers.util.Direction;
+import tools.refinery.viatra.runtime.rete.network.Node;
+import tools.refinery.viatra.runtime.rete.network.communication.Timestamp;
+
+/**
+ * A listener for update events concerning an Indexer.
+ * 
+ * @author Gabor Bergmann
+ * 
+ */
+public interface IndexerListener {
+    /**
+     * Notifies recipient that the indexer has just received an update. Contract: indexer already reflects the updated
+     * state.
+     * 
+     * @param direction
+     *            the direction of the update.
+     * @param updateElement
+     *            the tuple that was updated.
+     * @param signature
+     *            the signature of the tuple according to the indexer's mask.
+     * @param change
+     *            whether this was the first inserted / last revoked update element with this particular signature.
+     * @since 2.4
+     */
+    void notifyIndexerUpdate(Direction direction, Tuple updateElement, Tuple signature, boolean change, Timestamp timestamp);
+
+    Node getOwner();
+}