diff --git a/AlgebraicDataflowArchitectureModel/src/models/controlFlowModel/CallGraph.java b/AlgebraicDataflowArchitectureModel/src/models/controlFlowModel/CallGraph.java
index dc881c9..8bd6310 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/controlFlowModel/CallGraph.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/controlFlowModel/CallGraph.java
@@ -11,7 +11,7 @@
 import java.util.Set;
 
 public class CallGraph extends DirectedGraph {
-	protected Map<ResourceNode, StatefulObjectNode> statefulObjMap = null;
+	protected Map<ResourceNode, StatefulObjectNode> statefulObjMap;
 	
 	public CallGraph() {
 		statefulObjMap = new HashMap<>();