Question

So I have a big long query string that can either be …

//url=z&surl=y&time=z&codec=a264&acodec=mp3&width=400×100
or
//url=z&surl=y&time=z&optlevel=w

Im using request.getQueryString(“url”) to check if a) the qs is there and b) make sure its not null. This is all leading to a big messy set of if statements. I was just wondering if there is a better way to do it.

example..

if(request.getParameter("originalURL") != null &&
        request.getParameter("originalURL").equals("") && ................) 

Thanks guys

Answer 1

Sure, just refactor the duplicated code into methods or make use of an existing framework.

Basic kickoff example of refactored code:

String field1 = getField(request, "field1", true);
String field2 = getField(request, "field2", true);
String field3 = getField(request, "field3", false);

...

public static String getField(HttpServletRequest request, String fieldName, boolean required) throws ValidatorException {
    String fieldValue = request.getParameter(fieldName);
    if (fieldValue == null || fieldValue.trim().isEmpty()) {
        if (required) {
            throw new ValidatorException("Field is required");
        } else {
            fieldValue = null; // Make empty string null so that you don't need to hassle with equals("") afterwards.
        }
    }
    return fieldValue;
}

You can of course go a step further and adopt an existing MVC framework with validation (and conversion) capabilities, such as Sun JSF or Apache Struts.