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jsp网页登陆验证

来源:中文源码网    浏览:401 次    日期:2024-04-22 23:43:52
【下载文档:  jsp网页登陆验证.txt 】


jsp网页登陆验证
jsp登陆验证,网页登陆验证带验证码校验,登录功能之添加验证码
part_1:专门用于生成一个验证码图片的类:VerificationCode.java
package cn.mike.javase.test;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
import org.junit.Test;
/**
* @author : Administrator
* @function : 这是用来测试随机生成验证码图片的类;
*/
public class VerificationCode {
/**
* 单元测试,试一下能不能自动生成验证码图片
*/
// 这个函数是单元测试时使用的,这里private一下外面就调用不到了;
/* @Test */
/* public */private void test_fun() {
VerificationCode vc = new VerificationCode();
BufferedImage image = vc.getImage();
try {
// 生成验证码图片,并保存到指定的路径
VerificationCode.output(image, new FileOutputStream(new File(
".\\image\\vcode_2.jpg")));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
// 将随机生成的文本内容输出到控制台,用于校验
System.out.println(vc.getText());
}
private int w = 70;// 宽
private int h = 35;// 高
private String text;// 文本内容(验证码字符串)
private Random r = new Random();
private String[] fontNames = { "宋体", "华文楷体", "黑体", "微软雅黑", "楷体_GB2312" };
// 随机字符集合中不包括0和o,O,1和l,因为这些不易区分
private String codes = "23456789abcdefghijkmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYXZ";
// 验证码图片的背景色:白色
private Color bgColor = new Color(255, 255, 255);
/**
* 返回一个验证码图片buffer对象:BufferedImage
*/
public BufferedImage getImage() {
BufferedImage image = createImage();
// 获取绘图环境(画笔工具)
Graphics2D g2 = (Graphics2D) image.getGraphics();
// sb : 用来保存验证码字符串文本内容
StringBuilder sb = new StringBuilder();
for (int i = 0; i < 4; ++i) {// 随机生成4个字符
String s = randomChar() + "";
sb.append(s);
float x = i * 1.0F * w / 4;
g2.setFont(randomFont());
g2.setColor(randomColor());
g2.drawString(s, x, h - 5);
}
this.text = sb.toString();// 记录验证码文本内容
drawLine(image);// 画干扰线
return image;
}
/**
* @return 获取验证码文本内容
*/
public String getText() {
return text;
}
/**
* @param image
* @param out
* 将文本写到指定的输出流。比如本测试中FileOutputStream指定的保存路径
*/
public static void output(BufferedImage image, OutputStream out) {
try {
ImageIO.write(image, "jpeg", out);
} catch (IOException e) {
e.printStackTrace();
}
}
private void drawLine(BufferedImage image) {
Graphics2D g2 = (Graphics2D) image.getGraphics();
for (int i = 0; i < 3; ++i) {// 画3条干扰线
int x1 = r.nextInt(w);
int y1 = r.nextInt(h);
int x2 = r.nextInt(w);
int y2 = r.nextInt(h);
g2.setColor(Color.BLUE);
g2.drawLine(x1, y1, x2, y2);
}
}
private Color randomColor() {
int red = r.nextInt(150);
int green = r.nextInt(150);
int blue = r.nextInt(150);
return new Color(red, green, blue);
}
private Font randomFont() {
int index = r.nextInt(fontNames.length);
String fontName = fontNames[index];
int style = r.nextInt(4);
int size = r.nextInt(5) + 24;
return new Font(fontName, style, size);
}
private char randomChar() {
int index = r.nextInt(codes.length());
return codes.charAt(index);
}
private BufferedImage createImage() {
BufferedImage image = new BufferedImage(w, h,
BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = (Graphics2D) image.getGraphics();
g2.setColor(this.bgColor);
g2.fillRect(0, 0, w, h);
return image;
}
}
part_2:登录界面:Login.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>




My JSP 'Login.jsp' starting page








<%
String fdbkMsg = (String) request.getAttribute("fdbkMsg");
if (null == fdbkMsg) {
fdbkMsg = "";
}
%>
<%
Boolean logedIn = (Boolean) session.getAttribute("logedIn");
if (null == logedIn) {
logedIn = false;
} else if (logedIn) {
//如果在本次会话已经登陆,直接重定向到success-page-1
response
.sendRedirect("/ServletDemoProject/LOGIN-DEMO/success-page-1.jsp");
}
%>
<%
String username = "";
Cookie[] cookies = request.getCookies();
if ((null != cookies) && (cookies.length > 0)) {
for (Cookie c : cookies) {
if ("admin".equals(c.getValue())) {
username = "admin";
break;
}
}
}//end if-condition
%>




请登录:


method="post">

用户名:





密 码:





验证码:

id="img_src" />
换一张




<%=fdbkMsg%>












part_3:处理登录校验的servlet :LoginVerificationServlet.java
package cn.mike.servlet.test_1212;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.mike.javase.test.VerificationCode;
public class GetVerificationCodeServlet extends HttpServlet {
private static final long serialVersionUID = -3520994675366100452L;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 1.新建一个VerificationCode类;
VerificationCode vc = new VerificationCode();
// 2.从VerificationCode类中获取BufferedImage对象;
BufferedImage bufImage = vc.getImage();
// 3.同时获取验证码中的文本内容,并放到session域中, 用于校验;
String code_text = vc.getText();
request.getSession().setAttribute("code_text", code_text);
// 4.将生成的图片输出到客户端浏览器
VerificationCode.output(bufImage, response.getOutputStream());
}// end method-doGet
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// do same as GET-method :
doGet(request, response);
}// end method-doPost
}
part_4:成功登陆后的提示界面1:success-page-1.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>




My JSP 'success-page-1.jsp' starting page







<%
String username = (String) session.getAttribute("username");
if (null == username) {
//如果username为空值,说明不是通过正常渠道来的,转发到Login页面;
request.setAttribute("fdbkMsg", "别想走后门进来,赶紧登录!");
request.getRequestDispatcher("/LOGIN-DEMO/Login.jsp").forward(
request, response);
}
%>



<%=username%>已经成功登陆。


您可以选择浏览:


点这儿有精彩.


点这儿更精彩.


你敢点这儿吗.




part_5:成功登陆后的提示界面1:success-page-2.jsp
<%@ page language="java" import="java.util.Date" pageEncoding="UTF-8"%>
<%@ page language="java" import="java.text.SimpleDateFormat"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>




My JSP 'success-page-2.jsp' starting page







<%
String username = (String) session.getAttribute("username");
if (null == username) {
request.setAttribute("fdbkMsg", "呵呵嗒,这里是你来的地方吗?快登陆!");
//转发到登录界面:
request.getRequestDispatcher("/LOGIN-DEMO/Login.jsp").forward(
request, response);
}
SimpleDateFormat sDateFormat = new SimpleDateFormat("a");
Date today = new Date();
String am_pm_str = sDateFormat.format(today);
String am_pm_str_in_chinese = "";
if ("am".equalsIgnoreCase(am_pm_str)) {
am_pm_str_in_chinese = "上午";
} else
am_pm_str_in_chinese = "下午";
// set null;
sDateFormat = null;
today = null;
am_pm_str = null;
%>



<%=username%><%=am_pm_str_in_chinese%>好,能来到页面2真不简单.



以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持中文源码网。

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