1 files changed, 55 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/igraph/IGraphObserver.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/igraph/IGraphObserver.java
new file mode 100644
index 00000000..a282216d
--- /dev/null
+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/igraph/IGraphObserver.java
@@ -0,0 +1,55 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2012, Tamas Szabo, 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.rete.itc.igraph;
+
+/**
+ * Interface GraphObserver is used to observ the changes in a graph; edge and node insertion/deleteion.
+ *
+ * @author Tamas Szabo
+ *
+ */
+public interface IGraphObserver<V> {
+
+    /**
+     * Used to notify when an edge is inserted into the graph.
+     *
+     * @param source
+     *            the source of the edge
+     * @param target
+     *            the target of the edge
+     */
+    public void edgeInserted(V source, V target);
+
+    /**
+     * Used to notify when an edge is deleted from the graph.
+     *
+     * @param source
+     *            the source of the edge
+     * @param target
+     *            the target of the edge
+     */
+    public void edgeDeleted(V source, V target);
+
+    /**
+     * Used to notify when a node is inserted into the graph.
+     *
+     * @param n
+     *            the node
+     */
+    public void nodeInserted(V n);
+
+    /**
+     * Used to notify when a node is deleted from the graph.
+     *
+     * @param n
+     *            the node
+     */
+    public void nodeDeleted(V n);
+}