code: public T convert(Object value)
      {
          T result = null;
          if (value != null)
          {
              if (getValueClass().isInstance(value))
                  result = getValueClass().cast(value);
              else
                  result = convertFromString(value.toString());
          }
          return result;
      }
docs: Converts the given value object into an object of the value class specified by this Key.
  
  @param value the value to convert
  @return an object of the value class specified by this Key
  @see #convertFromString(String)