src/java.base/share/classes/sun/reflect/annotation/EnumConstantNotPresentExceptionProxy.java

*** 43,48 ****
--- 43,53 ----
      }
  
      protected RuntimeException generateException() {
          return new EnumConstantNotPresentException(enumType, constName);
      }
+ 
+     @Override
+     public String memberToString() {
+         return constName + " /* Not present! */";
+     }
  }