doPost.java

@Override
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  
  response.setContentType("text/html");
  java.util.Map<String, String[]> map = request.getParameterMap();
  String param = "";
  
  if (!map.isEmpty()){
    String values = map.get("vector");
    if (values != null){
      param = values[0];
    }
  }
  
  String bar = htmlEscape(param);
  Object[] obj = {"a", bar};
  response.getWriter().printf(java.util.Locale.US, "Formatted like: %1$s and %2$s.", obj);			

}