From c2bd11fb8844c2d02d73218f8b330acb731ff2a9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=A1bor=20Bergmann?= <gabor.bergmann@incquerylabs.com>
Date: Thu, 25 Mar 2021 21:31:30 +0100
Subject: [PATCH] #70 Force initialization of default Viatra query backends

---
 .../com/incquerylabs/v4md/ViatraQueryAdapter.java    | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/com.incquerylabs.v4md/src/main/com/incquerylabs/v4md/ViatraQueryAdapter.java b/com.incquerylabs.v4md/src/main/com/incquerylabs/v4md/ViatraQueryAdapter.java
index c88a466..8379b1c 100644
--- a/com.incquerylabs.v4md/src/main/com/incquerylabs/v4md/ViatraQueryAdapter.java
+++ b/com.incquerylabs.v4md/src/main/com/incquerylabs/v4md/ViatraQueryAdapter.java
@@ -18,6 +18,8 @@
 import org.eclipse.viatra.query.runtime.api.IQuerySpecification;
 import org.eclipse.viatra.query.runtime.api.ViatraQueryEngineOptions;
 import org.eclipse.viatra.query.runtime.exception.ViatraQueryException;
+import org.eclipse.viatra.query.runtime.localsearch.matcher.integration.LocalSearchEMFBackendFactory;
+import org.eclipse.viatra.query.runtime.rete.matcher.ReteBackendFactory;
 
 import com.incquerylabs.v4md.internal.MagicDrawProjectScope;
 import com.incquerylabs.v4md.internal.NopQueryBackend;
@@ -37,6 +39,16 @@ public class ViatraQueryAdapter extends AdapterImpl {
 			"Cannot initialize VIATRA Query Engine until the project is loaded.";
 	private static final Logger LOGGER = Logger.getLogger(ViatraQueryAdapter.class);
 	
+	
+	static {
+		ViatraQueryEngineOptions.setSystemDefaultBackends(
+				ReteBackendFactory.INSTANCE, 
+				ReteBackendFactory.INSTANCE, 
+				LocalSearchEMFBackendFactory.INSTANCE
+		);
+	}
+	
+	
 	private Optional<AdvancedViatraQueryEngine> engine = Optional.empty();
 	private Project project;
 	private boolean engineDisposable = true;