title: How to return HTTP error code from servlet filter?
body: <p>I have pages in my web application which are accessible only by the administrator. I wrote filter, but I don't understand how to return HTTP error code(403) from the filter if user isn't the admin.</p>
  
  <pre><code>public class AdminFilter implements Filter {
      @Override
      public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
          String username = servletRequest.getParameter("username");
          String password = servletRequest.getParameter("password");
  
          UserDao userDaoImpl = new UserDaoImpl();
          if(userDaoImpl.findByUsername(username).getPassword().equals(password)) {
              filterChain.doFilter(servletRequest, servletResponse);
          } else {
              //respond with 403
          }
      }
  }
  </code></pre>
  
  <p>I understand that I can redirect to my custom 403 page but I'm wondering how to return HTTP error code.</p>