src/java.compiler/share/classes/javax/lang/model/element/UnknownAnnotationValueException.java

*** 77,87 ****
      }
  
      /**
       * Returns the additional argument.
       *
!      * @return the additional argument
       */
      public Object getArgument() {
          return parameter;
      }
  }
--- 77,87 ----
      }
  
      /**
       * Returns the additional argument.
       *
!      * @return the additional argument, or {@code null} if unavailable
       */
      public Object getArgument() {
          return parameter;
      }
  }