diff --git a/gson/src/test/java/com/google/gson/functional/PrettyPrintingTest.java b/gson/src/test/java/com/google/gson/functional/PrettyPrintingTest.java
index 270e3566..8209989e 100644
--- a/gson/src/test/java/com/google/gson/functional/PrettyPrintingTest.java
+++ b/gson/src/test/java/com/google/gson/functional/PrettyPrintingTest.java
@@ -40,7 +40,7 @@ public class PrettyPrintingTest extends TestCase {
   private static int PRINT_MARGIN = 80;
   private static int RIGHT_MARGIN = 4;
 
-  private static boolean DEBUG = false;
+  private static final boolean DEBUG = false;
 
   private Gson gson;