Userservlet登录数据处理，包括访问页面次数处理：

package com.szxy.test;

import java.io.IOException;

import javax.servlet.ServletContext;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class Uservlet extends HttpServlet {

	@Override

	protected void service(HttpServletRequest req, HttpServletResponse resp)

			throws ServletException, IOException {

		req.setCharacterEncoding("utf-8");//请求编码格式

		resp.setContentType("text/html;charset=utf-8");//响应编码格式

		String uname = req.getParameter("uname");

		String pwd = req.getParameter("pwd");

		//创建session

		HttpSession session = req.getSession();

		if ("yxf".equals(uname)&&"wangjing".equals(pwd)) {

			//先获取公共资源对象

			ServletContext sc = this.getServletContext();

			Object obj1 = sc.getAttribute("nums");

			Object obj2 = sc.getAttribute("number");

			if (obj1!=null) {

				int nums=(Integer) obj1;

				nums++;

				sc.setAttribute("nums", nums);

			} else {

				sc.setAttribute("nums", 1);

			}

			if (obj2!=null) {

				int number=(Integer) obj2;

				number++;

				sc.setAttribute("number", number);

			} else {

				sc.setAttribute("number", 1);

			}

			//登录成功，将uname放入session中

			session.setAttribute("uname", uname);

			resp.sendRedirect("index");

		}else {

			//创建标记，将标记放在session中

			session.setAttribute("false", "loginfalse");

			resp.sendRedirect("dl");

//			req.getRequestDispatcher("dl").forward(req, resp);

			return;

		}

	}

}

NumberServlet：将访问页面次数储存，初始化页面的时候从文件取出次数，关闭服务器的时候，保存次数。

package com.szxy.test;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.OutputStreamWriter;

import javax.servlet.ServletContext;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

public class NumberServlet extends HttpServlet {

	@Override

	public void init() throws ServletException {

		//先获取公共资源

		ServletContext sc = this.getServletContext();

		//获取计数器文件位置(文件的绝对路径，动态获取)

		String path = sc.getRealPath("number/num.txt");

		//获取文件

		File file=new File(path);

		//读取文件流对象

		FileInputStream fis=null;

		InputStreamReader isr=null;

		BufferedReader br=null;

		try {

			fis=new FileInputStream(file);

			isr=new InputStreamReader(fis);

			br=new BufferedReader(isr);

			//获取计数器公共资源

			String number = br.readLine();

			System.out.println("-----------------"+number+"-------------");

			//将数据存储到公共资源中

			sc.setAttribute("number",Integer.parseInt(number));

		} catch (Exception e) {

			e.printStackTrace();

		}finally{

			try {

				fis.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

			try {

				isr.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

			try {

				br.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

		}

	}

	@Override

	public void destroy() {

		//先获取共享资源对象

		ServletContext sc = this.getServletContext();

//		获取计数器

		int number = (Integer)sc.getAttribute("number");

		//获取计数器文件位置(文件的绝对路径，动态获取)

		String path = sc.getRealPath("number/num.txt");

		//将计数器存储到文件中

		File file=new File(path);

		//获取资源的流对象

		BufferedWriter bw=null;

		OutputStreamWriter osw=null;

		FileOutputStream fos=null;

		try {

			fos=new FileOutputStream(file);

			osw=new OutputStreamWriter(fos);

			bw=new BufferedWriter(osw);

			//将资源写入文件中

			bw.write(number+"");

			//刷新

			bw.flush();

		} catch (Exception e) {

			e.printStackTrace();

		}finally{

			try {

				fos.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

			try {

				osw.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

			try {

				bw.close();

			} catch (IOException e) {

				// TODO Auto-generated catch block

				e.printStackTrace();

			}

		}

	}

}

IndexServlet登录成功页面：

package com.szxy.test;

import java.io.IOException;

import javax.servlet.ServletContext;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class IndexServlet extends HttpServlet {

	@Override

	protected void service(HttpServletRequest req, HttpServletResponse resp)

			throws ServletException, IOException {

		req.setCharacterEncoding("utf-8");

		resp.setContentType("text/html;charset=utf-8");

		//获取公共资源对象

		ServletContext sc = this.getServletContext();

		int num =(Integer)sc.getAttribute("nums");

		int n = (Integer)sc.getAttribute("number");

		resp.getWriter().write("<html>");

		resp.getWriter().write("<head>");

		resp.getWriter().write("</head>");

		resp.getWriter().write("<body>");

		resp.getWriter().write("<h1 >欢迎"+req.getSession().getAttribute("uname")+"登录成功</h1>");

		resp.getWriter().write("<h4 align=right>当前在线人数："+num+"</h4>");

		resp.getWriter().write("<h4 align=right>页面被访问："+n+"次</h4>");

		resp.getWriter().write("<hr/>");

		resp.getWriter().write("</body>");

		resp.getWriter().write("</html>");

	}

}

DLuServlet 登录界面：

package com.szxy.test;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class DLuServlet extends HttpServlet {

	@Override

	protected void service(HttpServletRequest req, HttpServletResponse resp)

			throws ServletException, IOException {

		req.setCharacterEncoding("utf-8");

		resp.setContentType("text/html;charset=utf-8");

		HttpSession session = req.getSession();

		String str = (session.getAttribute("false")==null?"":"用户名或密码错误");

		session.invalidate();

		resp.getWriter().write("<html>");

		resp.getWriter().write("<head>");

		resp.getWriter().write("</head>");

		resp.getWriter().write("<body>");

		resp.getWriter().write("<form action='user' method='post'/>");

		resp.getWriter().write("<font color='red'>"+str+"</font>");

		resp.getWriter().write("<br/>");

		resp.getWriter().write("用户名：<input type='text' name='uname' value='' /><br/>");

		resp.getWriter().write("密码：<input type='password' name='pwd' value='' /><br/>");

		resp.getWriter().write("<input type='submit' value='登录' />");

		resp.getWriter().write("</body>");

		resp.getWriter().write("</html>");

	}

}

最新文章

  1. Linux基础命令-有关于目录的命令
  2. php中Jpgraph的运用
  3. ERP反馈信息管理（十九）
  4. Hash Table构建
  5. 使用info.plist（或工程名-info.plist）向程序中添加软件Build ID或者版本号信息
  6. MVC3的一个意外的异常 String was not recognized as a valid Boolean. @using (Html.BeginForm())
  7. JavaEmail
  8. JVM JMM
  9. 全国计算机等级考试二级教程-C语言程序设计_第11章_对函数的进一步讨论
  10. Unknown
  11. C#数字类型及运算符
  12. 如何巧妙的利用selenium和requests组合来进行操作需要登录的页面
  13. cordova插件汇总
  14. 从koa-session源码解读session本质
  15. c++ protected 访问限定
  16. 团队作业M1反思
  17. Java集合list,map,set区别及遍历
  18. golang并发ping主机
  19. JS播放声音
  20. iOS：获取 NSDate 的年

热门文章

  1. jquery倒计时代码
  2. 201871010114-李岩松《面向对象程序设计（java）》第四周学习总结
  3. （转）白话数字签名(2)——软件&amp;设备
  4. 深入理解 DNS
  5. MyBatis批量插入模板
  6. Python 面向对象-上篇
  7. nyoj 66-分数拆分 （Java，暴力）
  8. nyoj 100-1的个数 (因为只统计1的个数，连栈都不需要了)
  9. 理解MySQL数据库事务-隔离性
  10. 逻辑卷LVM