diff --git a/AlgebraicDataflowArchitectureModel/src/application/editor/stages/ControlFlowModelingStage.java b/AlgebraicDataflowArchitectureModel/src/application/editor/stages/ControlFlowModelingStage.java
index 38af5e4..a43e0ca 100644
--- a/AlgebraicDataflowArchitectureModel/src/application/editor/stages/ControlFlowModelingStage.java
+++ b/AlgebraicDataflowArchitectureModel/src/application/editor/stages/ControlFlowModelingStage.java
@@ -36,7 +36,7 @@
 	private ControlFlowModelingStageStatus curState;
 	
 	private ControlFlowGraph controlFlowGraph = null;
-	private PopupMenuBase popupMenu;
+	private final PopupMenuBase popupMenu;
 	
 	private mxCell selectedCellOnAnyEvent = null;