web巩固（三）.3

实现在主界面的退出操作，过滤器需要放过退出操作

package controller;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet("/logout")
public class LogoutController extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.getSession().removeAttribute("loginUser");//清空session
        //覆盖浏览器cookie实现清空效果
        Cookie cookie=new Cookie("tokenId","-1");
        cookie.setMaxAge(0);
        resp.addCookie(cookie);
        resp.sendRedirect("http://localhost:8080/qxgl07/login.jsp");
    }
}

验证码点击刷新功能

var no=1;
function reloadCode() {
    //改验证码，<img src="2.jpg">重新设置src属性
    var img =document.getElementById("codeImg");
    img.src='checkcode?no='+no++;
}