1 files changed, 27 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime-matchers/src/main/java/tools/refinery/viatra/runtime/matchers/backend/IUpdateable.java b/subprojects/viatra-runtime-matchers/src/main/java/tools/refinery/viatra/runtime/matchers/backend/IUpdateable.java
new file mode 100644
index 00000000..baf7144a
--- /dev/null
+++ b/subprojects/viatra-runtime-matchers/src/main/java/tools/refinery/viatra/runtime/matchers/backend/IUpdateable.java
@@ -0,0 +1,27 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2014, Bergmann Gabor, 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.matchers.backend;
+
+import tools.refinery.viatra.runtime.matchers.tuple.Tuple;
+
+/**
+ * Internal interface for the query backend to singal an update to a query result.
+ * @author Bergmann Gabor
+ * @since 0.9
+ *
+ */
+public interface IUpdateable {
+    
+    /**
+     * This callback method must be free of exceptions, even {@link RuntimeException}s (though not {@link Error}s).
+     * @param updateElement the tuple that is changed
+     * @param isInsertion true if the tuple appeared in the result set, false if disappeared from the result set
+     */
+    public void update(Tuple updateElement, boolean isInsertion);
+}