diff --git a/java/src/com/android/inputmethod/keyboard/Key.java b/java/src/com/android/inputmethod/keyboard/Key.java
index 33b55b5d3..4b4ffdbaf 100644
--- a/java/src/com/android/inputmethod/keyboard/Key.java
+++ b/java/src/com/android/inputmethod/keyboard/Key.java
@@ -275,7 +275,7 @@ public class Key {
     }
 
     private static boolean isDigitPopupCharacter(CharSequence label) {
-        return label.length() == 1 && Character.isDigit(label.charAt(0));
+        return label != null && label.length() == 1 && Character.isDigit(label.charAt(0));
     }
 
     private static CharSequence[] filterOutDigitPopupCharacters(CharSequence[] popupCharacters) {