Java get cookie method

Java has an abundance of methods for handling cookies. Given a HttpServletRequest one can use the useful getCookies() method.

This method returns an array of cookie objects.

The bare essentials:

public static String getCookieValue(HttpServletRequest request, String name)
{
  Cookie[] cookies = request.getCookies();
  for (Cookie cookie : cookies)
  {
    if (cookie.getName().equals(name))
      return cookie.getValue();
  }

  return "";
}

The below code shows this would work in a Utils method:

/**
* Gets cookie value based for a given cookie name.
*
* @param request the actual HttpServletRequest object which holds the request header information.
* @param name a string for the name of the cookie been requested.
* @return Either an empty string if no such cookie is found or the actual value of the cookie.
* @throws IllegalAccessException
*/
public static String getCookieValue(HttpServletRequest request, String name) throws IllegalAccessException
{
  // Be good check your parameters first.
  if (request != null && name != null && !name.equals(""))
  {
    // Here we return all cookie object. If no cookie was set then will be an empty array.
    Cookie[] cookies = request.getCookies();

   // Loop through each cookie.
   for (Cookie cookie : cookies)
   {
     if (cookie.getName().equals(name))
     {
       // Return value if the name is matched.
      return cookie.getValue();
     }
   }
 }
 else
 {
   // Incorrect parameter list.
   throw new IllegalArgumentException();
 }

 // I will be doing another post on Log4J logger; you can live without this just print to the console.
 logger.warn("No such cookie with name:"+name+" returned empty string by default.");

 return "";
}

One caveat is if you are using an IDE to test this code most IDEs (as Eclipse did) will ignore any system classpath, and rely on project-specific settings. You will need to add external JARs to your project path.