<%! 

// Note lack of try/catch for NumberFormatException if

// value is null or malformed.

private double toDouble(String value) {

  return(Double.valueOf(value).doubleValue());

}

%>

<% 

double furlongs = toDouble(request.getParameter("furlongs")); 

double fortnights = toDouble(request.getParameter("fortnights"));

double speed = furlongs/fortnights;

%>

  
Distance: <%= furlongs %> furlongs.

  
Time: <%= fortnights %> fortnights.

  
Speed: <%= speed %> furlongs per fortnight.

Listing 11.6 SpeedErrors.jsp