1 files changed, 37 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/IMatchUpdateListener.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/IMatchUpdateListener.java
new file mode 100644
index 00000000..23c64537
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/api/IMatchUpdateListener.java
@@ -0,0 +1,37 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2012, 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.api;
+
+/**
+ * An interface for low-level notifications about match appearance and disappearance.
+ * 
+ * <p>
+ * See {@link ViatraQueryMatcher#addCallbackOnMatchUpdate(IMatchUpdateListener, boolean)} for usage. Clients should
+ * consider using {@link MatchUpdateAdapter} or deriving their implementation from it.
+ * 
+ * @author Bergmann Gabor
+ * 
+ */
+public interface IMatchUpdateListener<Match extends IPatternMatch> {
+    /**
+     * Will be invoked on each new match that appears.
+     * 
+     * @param match
+     *            the match that has just appeared.
+     */
+    public void notifyAppearance(Match match);
+
+    /**
+     * Will be invoked on each existing match that disappears.
+     * 
+     * @param match
+     *            the match that has just disappeared.
+     */
+    public void notifyDisappearance(Match match);
+}