Servlet实现简单的用户登录

灰太狼 2022-07-16 17:41 206阅读 0赞

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>登录页面</title>
    </head>
    <body>
    <form action="loginServlet" method="post">
    	用户名：<input type="text" id="uname" name="uname"><br><br>
    	密码：<input type="password" id="pwd" name="pwd"><br><br>
    	<input type="submit" value="登录">  
    	<input type="reset" value="重置"> 
    </form>
    </body>
    </html>

loginServlet.java

package com.java;
    
    import java.io.IOException;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    
    /**
     * Servlet implementation class loginServlet
     */
    @WebServlet("/loginServlet")
    public class loginServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
    
    	/**
    	 * @see HttpServlet#HttpServlet()
    	 */
    	public loginServlet() {
    		super();
    		// TODO Auto-generated constructor stub
    	}
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
    	 *      response)
    	 */
    	protected void doGet(HttpServletRequest request,
    			HttpServletResponse response) throws ServletException, IOException {
    		HttpSession session = request.getSession();//获取session
    		Object name = session.getAttribute("name");//从session中获取用户名
    		Object pwd = session.getAttribute("pwd");//从session获取用户密码
    		System.out.println(name+":"+pwd); //测试一下，输出获取的用户名和密码
    		session.invalidate(); //注销session
    		response.sendRedirect("login.jsp"); //跳转到login.jsp页面
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
    	 *      response)
    	 */
    	protected void doPost(HttpServletRequest request,
    			HttpServletResponse response) throws ServletException, IOException {
    		// doGet(request, response);
    		// 设置编码为utf-8
    		request.setCharacterEncoding("utf-8");
    		response.setCharacterEncoding("utf-8");
    
    		// 获取用户名和密码
    		String name = request.getParameter("uname");
    		String pwd = request.getParameter("pwd");
    
    		// 校验用户名和密码是否正确
    		if ("admin".equals(name) && "123".equals(pwd)) {// 验证成功
    			HttpSession session = request.getSession();//获取session
    			session.setAttribute("name", name);// 将用户名和密码保存在session中
    			session.setAttribute("pwd", pwd);// 将用户名和密码保存在session中
    			response.sendRedirect("success.jsp");// 跳转到success.jsp页面
    		} else {// 校验不成功，则留在跳转到login.jsp页面
    			response.sendRedirect("login.jsp");
    		}
    	}
    
    }

success.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>登录成功页面</title>
    </head>
    <body>
    登录成功！${name},${pwd}<form action="loginServlet" method="get"><input type="submit" value="注销登录"></form>
    </body>
    </html>