1 files changed, 34 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/scope/ViatraBaseIndexChangeListener.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/scope/ViatraBaseIndexChangeListener.java
new file mode 100644
index 00000000..b746e637
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/scope/ViatraBaseIndexChangeListener.java
@@ -0,0 +1,34 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2013, Abel Hegedus, 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.api.scope;
+
+/**
+ * Listener interface for change notifications from the VIATRA Base index.
+ * 
+ * @author Abel Hegedus
+ * @since 0.9
+ *
+ */
+public interface ViatraBaseIndexChangeListener {
+
+    /**
+     * NOTE: it is possible that this method is called only ONCE! Consider returning a constant value that is set in the constructor.
+     * 
+     * @return true, if the listener should be notified only after index changes, false if notification is needed after each model change 
+     */
+    public boolean onlyOnIndexChange();
+    
+    /**
+     * Called after a model change is handled by the VIATRA Base index and if <code>indexChanged == onlyOnIndexChange()</code>.
+     *  
+     * @param indexChanged true, if the model change also affected the contents of the base index
+     */
+    public void notifyChanged(boolean indexChanged);
+    
+}