1 files changed, 1 insertions, 1 deletions
diff --git a/luni/src/main/java/java/util/MissingFormatWidthException.java b/luni/src/main/java/java/util/MissingFormatWidthException.java
index b6d0ca6..0a3b5ae 100644
--- a/luni/src/main/java/java/util/MissingFormatWidthException.java
+++ b/luni/src/main/java/java/util/MissingFormatWidthException.java
@@ -36,7 +36,7 @@ public class MissingFormatWidthException extends IllegalFormatException {
      */
     public MissingFormatWidthException(String s) {
         if (s == null) {
-            throw new NullPointerException();
+            throw new NullPointerException("s == null");
         }
         this.s = s;
     }