public static URL resolve(String s) throws MalformedURLException 
{
        return resolve(s, null);
}

 public static URL resolve(String s,
    URL url) throws MalformedURLException 
{
        URL resolve = null;
	// construct a URL via the following heuristics:
	//
	//    if arg contains ":/" then
	//        assume a valid uri
	//    else if url arg is specified
	//        construct uri
	//    else if an absolute path then
	//        construct file uri
	//    else
	//        construct file uri by prepending the
	//        working directory
	if (s.indexOf("://")  > -1 ||
            s.indexOf("file:")  > -1 ) {
	    resolve = new URL(s);
	} else if (url != null) {
	    resolve = new URL(url, s);
	} else if (s.startsWith(File.separator) ||
            s.startsWith("/") ||
	    (s.length()  >= 2 &&
	        Character.isLetter(s.charAt(0)) &&
	        s.charAt(1) == ':')) {
            String fName = s;
            try {
                fName = (String)(new File(s)).getCanonicalPath();
            } catch (NullPointerException npe) {
            } catch (IOException npe) {
            }
	    resolve = new URL("file", "", fName);
	} else {
            String path = System.getProperty("user.dir") +
                File.separator + s;
	    resolve = new URL("file", "", path);
	}
        if (! resolve.getProtocol().equalsIgnoreCase(
                org.apache.tomcat.core.Constants.Request.WAR) &&
            resolve.getFile().toLowerCase().endsWith(
                "." + Constants.MIME.WAR)) {
            URL u = new URL(Constants.MIME.WAR + ":" +
                resolve.toString());
            resolve = u;
        }
        resolve = new URL(trim(resolve.toString(), ".", ".."));
        resolve = new URL(trim(resolve.toString(), "./"));
	return resolve;
}