改进版登录与注册实现-优快云博客

本文链接：https://blog.youkuaiyun.com/Autumn_bell/article/details/51968091

servlet学习（三）

标签： servlet jsp

做了一些小改变，登录servlet使用url转发方式传递参数，页面可以直接用el表达式获取信息，注册页面servlet不变，通过jstl取代小脚本并将值放入自己定义的作用域当中，再用el表达式取值。

loginServlet

package controller;

import service.LoginService;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * Created by Fate on 2016/7/1.
 */
public class LoginControllerServlet extends HttpServlet {


    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String username = req.getParameter("username");
        String password = req.getParameter("password");
        LoginService LoginService = new LoginService();
        boolean result = LoginService.login(username, password);
        if (result) {
            resp.sendRedirect("wel.jsp");
            return;
        }
        String msg = "用户名或密码不正确";
        req.setAttribute("msg",msg);
        req.getRequestDispatcher("login.jsp").forward(req,resp);
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doPost(req, resp);
    }
}

login.jsp

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>login</title>
    <meta charset="utf-8">
    <meta name="keyword" content="登录">
    <meta name="description" content="">
    <!--css/js-->
    <style type="text/css"...>
</head>
<body>
<!--S form-->
<div class="my_text">
    <a>登录界面</a>
</div>
<!--E form-->
<!--S form-->
<form action="loginControllerServlet" method="get" class="my_form">
    <input class="return_msg" value="${msg}:${param.username}" placeholder=" ">
    <input name="username" placeholder="please enter your name" type="text" class="my_input">
    <input name="password" placeholder="please enter password" type="password" class="my_input">
    <input type="submit" value="submit" class="my_button">
    <input type="reset" value="reset" class="my_button">
</form>
<!--E form-->

<!--S span-->
<div class="span">
    <span>don't have account?</span>
    <a href="register.jsp">Now register!</a>
</div>
<!--E span-->
</body>
</html>

register.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>register</title>
    <meta charset="utf-8">
    <meta name="keyword" content="注册">
    <meta name="description" content="">
    <!--css/js-->
    <style type="text/css"...>
</head>
<body>
<!--S text-->
<div class="my_text">
    <a>注册界面</a>
</div>
<!--E text-->
<!--S form-->
<div>
    <form action="registerControllerServlet" method="post" class="my_form">
        <c:if test="${param.code==10001}">
            <c:set value="用户已存在" var="msg" scope="request"/>
        </c:if>
        <c:if test="${param.code==10000}">
            <c:set value="必要参数为空" var="msg" scope="request"/>
        </c:if>
        <input class="return_msg" value="${msg}" placeholder=" ">
        <input name="username" placeholder="please enter your name" type="text" class="my_input" value="">
        <input name="password" placeholder="please enter password" type="password" class="my_input">
        <input name="age" placeholder="please enter your age" type="password" class="my_input">
        <input type="submit" value="submit" class="my_button">
        <input type="reset" value="reset" class="my_button">
    </form>
</div>
<!--E form-->
<!--S span-->
<div class="span">
    <span>already have an account?</span>
    <a href="login.jsp">Go to login!</a>
</div>
<!--E span-->
</body>
</html>