anchor.diff:  
   <%
       String user = request.getParameter("user");
  +    String homewiki = request.getParameter("wiki");
  +    if (homewiki == null)
  +        homewiki = "en.wikipedia.org";
  +    else
  +        homewiki = ServletUtils.sanitizeForAttribute(homewiki);
  +
       if (user != null)
       {
           // create download prompt
  
positive.code: 
  <p>
  <form action="./imagecci.jsp" method=GET>
      
  <p>User to survey: 
  <input type=text name=user required>
  <input type=submit value="Survey user">
  </form>
  
  
negative.code:         response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode(user, "UTF-8") + ".txt");
  
          // get results
          Wiki wiki = new Wiki(homewiki);
          Wiki.User wpuser = wiki.getUser(user);
          String[][] survey = ContributionSurveyor.imageContributionSurvey(wiki, wpuser);
  
  