test/java/text/Format/NumberFormat/Bug4990596.java

@@ -33,10 +33,11 @@
 
     public static void main(String[] args) {
         new DecimalFormat().format(new MutableInteger(0));
     }
 
+    @SuppressWarnings("serial")
     public static class MutableInteger extends Number {
         public int value;
 
         public MutableInteger() {
         }