diff --git a/src/main/java/dev/sillyangel/calc/Calculator.java b/src/main/java/dev/sillyangel/calc/Calculator.java
index 4db201e..6800ecb 100644
--- a/src/main/java/dev/sillyangel/calc/Calculator.java
+++ b/src/main/java/dev/sillyangel/calc/Calculator.java
@@ -28,6 +28,8 @@ import dev.sillyangel.calc.CalculatorModes;
 public class Calculator extends JFrame implements KeyListener {
 	
 	private static final String PREF_NODE_NAME = "dev/sillyangel/calc";
+	private static boolean
+	private static int
 	public static final Preferences prefs = Preferences.userRoot().node(PREF_NODE_NAME);
 	public static String APPILCATION_VERSION = "1.0.0pre";
 	private static final long serialVersionUID = 1L;