title: Servlet reflected cross site scripting vulnerability
body: <p>I've analyzed a code with Findbugs and it reported a warning for </p>
  
  <blockquote>
    <p>servlet reflected cross site scripting vulnerability.</p>
  </blockquote>
  
  <p>Code is like that and the 3rd line throws the warning:</p>
  
  <pre><code>String tickName = request.getParameter("ticko");
  PrintWriter w = response.getWriter();
  w.println("Unable to perform tickonem '" + tickName +"' because no tick with that name is active!"); //this line throws warning.
  </code></pre>
  
  <p>What is the real reason for it and how to fix it?</p>