百分求购一个登陆模块--要求有MD5加密和验证码

要使用struts就更好了
也可以发到我邮箱[email protected]

验证码用个随机数，放入session就可以了yz=Int((8999)*Rnd +1009)这个是4位的
Int((89999)*Rnd +10009)5位，依次类推
session("yz")=yz

Md5.java//-----------------------------------
package cn.com.ouyang.crypto;
/**
* <p>Title: MD5加密算法(推荐)</p>
* <p>Description: MD5加密,返回加密后的大写字符串</p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: </p>
* @author ouyang
* @version 1.0
*/import java.security.*;
//import java.math.*;public  class Md5 {
  public static final String MD5 = "MD5";
  public static String MD5(String sInput) {
    //输入不能为空
    if (sInput.trim() == null) {
      return "null";
    }    //指定采用MD5算法    String hs = "";
    try{
     MessageDigest md = MessageDigest.getInstance(Md5.MD5);      //按照系统缺省的字符编码方式把sInput 转换成字节，并把结果存到一新的字节数组buffer中
      //byte buffer[] = sInput.getBytes();
      md.update(sInput.getBytes());
      byte buffer[] = md.digest();
      String stmp = "";      for (int n = 0; n < buffer.length; n++) {
        stmp = Integer.toHexString(buffer[n] & 0xff);
        if (stmp.length() == 1)
          hs = hs + "0" + stmp;
        else
          hs = hs + stmp;
      }
    }catch(NoSuchAlgorithmException e){
      System.out.println("----NoSuchAlgorithmException----");
    }
      return hs.toUpperCase();  }
  public static void main(String[] a) {
    Md5 my = new Md5();      System.out.println(my.MD5("a"));  }
}

image.jsp
<%@ page contentType="image/jpeg" import="java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*" %>
<%!
Color getRandColor(int fc,int bc){//给定范围获得随机颜色
        Random random = new Random();
        if(fc>255) fc=255;
        if(bc>255) bc=255;
        int r=fc+random.nextInt(bc-fc);
        int g=fc+random.nextInt(bc-fc);
        int b=fc+random.nextInt(bc-fc);
        return new Color(r,g,b);
        }
%>
<%
//设置页面不缓存
response.setHeader("Pragma","No-cache");
response.setHeader("Cache-Control","no-cache");
response.setDateHeader("Expires", 0);// 在内存中创建图象
int width=60, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);// 获取图形上下文
Graphics g = image.getGraphics();//生成随机类
Random random = new Random();// 设定背景色
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);//设定字体
g.setFont(new Font("Times New Roman",Font.PLAIN,18));//画边框
//g.setColor(new Color());
//g.drawRect(0,0,width-1,height-1);
// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160,200));
for (int i=0;i<155;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
        int xl = random.nextInt(12);
        int yl = random.nextInt(12);
g.drawLine(x,y,x+xl,y+yl);
}// 取随机产生的认证码(4位数字)
//String rand = request.getParameter("rand");
//rand = rand.substring(0,rand.indexOf("."));
String sRand="";
for (int i=0;i<4;i++){
    String rand=String.valueOf(random.nextInt(10));
    sRand+=rand;
    // 将认证码显示到图象中
    g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));//调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
    g.drawString(rand,13*i+6,16);
}// 将认证码存入SESSION
session.setAttribute("rand",sRand);
// 图象生效
g.dispose();// 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
%>
a.jsp
<%@ page contentType="text/html;charset=gb2312" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>认证码输入页面</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<META HTTP-EQUIV="Pragma" CONTENT="no-cache">
<META HTTP-EQUIV="Cache-Control" CONTENT="no-cache">
<META HTTP-EQUIV="Expires" CONTENT="0">
</head>
<body>
<form method=post action="check.jsp">
<table>
<tr>
<td align=left>系统产生的认证码：</td>
<td><img border=0 src="image.jsp"></td>
</tr>
<tr>
<td align=left>输入上面的认证码：</td>
<td><input type=text name=rand maxlength=4 value=""></td>
</tr>
<tr>
<td colspan=2 align=center><input type=submit value="提交检测"></td>
</tr>
</form>
</body>
</html>
check.jsp<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<html>
<head>
<title>认证码验证页面</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<META HTTP-EQUIV="Pragma" CONTENT="no-cache">
<META HTTP-EQUIV="Cache-Control" CONTENT="no-cache">
<META HTTP-EQUIV="Expires" CONTENT="0">
</head><body>
<%
String rand = (String)session.getAttribute("rand");
String input = request.getParameter("rand");
%>
系统产生的认证码为： <%= rand %><br>
您输入的认证码为： <%= input %><br>
<br>
<%
  if (rand.equals(input)) {
%>
<font color=green>输入相同，认证成功！</font>
<%
  } else {
%>
<font color=red>输入不同，认证失败！</font>
<%
  }
%>
</body>
</html>

以上分别是Md5加密以及图形验证码的例子该图形验证码中只取数字作验证码，如果想要用字母和数字一起作为验证码则需要稍微修改一下
也就是需要一个随机生成字母和数字的方法，可引用Apache的包 org.apache.commons.lang.RandomStringUtils 类，如果不想引用类可以自己编译一下这个文件// DeCompiled : RandomStringUtils.class
package org.apache.commons.lang;
import java.util.Random;
public class RandomStringUtils
{
    private static final Random RANDOM = new Random();
    public RandomStringUtils()
    {
    }
    public static String random(int count)
    {
        return random(count, false, false);
    }
    public static String randomAscii(int count)
    {
        return random(count, 32, 127, false, false);
    }
    public static String randomAlphabetic(int count)
    {
        return random(count, true, false);
    }
    public static String randomAlphanumeric(int count)
    {
        return random(count, true, true);
    }
    public static String randomNumeric(int count)
    {
        return random(count, false, true);
    }
    public static String random(int count, boolean letters, boolean numbers)
    {
        return random(count, 0, 0, letters, numbers);
    }
    public static String random(int count, int start, int end, boolean letters, boolean numbers)
    {
        return random(count, start, end, letters, numbers, null);
    }
    public static String random(int count, int start, int end, boolean letters, boolean numbers, char set[])
    {
        if(start == 0 && end == 0)
        {
            end = 122;
            start = 32;
            if(!letters && !numbers)
            {
                start = 0;
                end = 0x7fffffff;
            }
        }
        StringBuffer buffer = new StringBuffer();
        int gap = end - start;
        while(count-- != 0)
        {
            char ch;
            if(set == null)
                ch = (char)(RANDOM.nextInt(gap) + start);
            else
                ch = set[RANDOM.nextInt(gap) + start];
            if(letters && numbers && Character.isLetterOrDigit(ch) || letters && Character.isLetter(ch) || numbers && Character.isDigit(ch) || !letters && !numbers)
                buffer.append(ch);
            else
                count++;
        }
        return buffer.toString();
    }
    public static String random(int count, String set)
    {
        return random(count, set.toCharArray());
    }
    public static String random(int count, char set[])
    {
        return random(count, 0, set.length - 1, false, false, set);
    }
}
在image.jsp中for (int i=0;i<4;i++){
    //String rand=String.valueOf(random.nextInt(10));
String rand=String.valueOf(RandomStringUtils.random(1,true,true));//将上面一句替换成这句
    sRand+=rand;
    // 将认证码显示到图象中
    g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));//调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
    g.drawString(rand,13*i+6,16);
}
即可生成字母数字组合的验证码

看蓝色巨人 IBM 怎么解释 JCE 的使用。搜索 IBM.com 下 DeveloperWorks 精品教程。Java安全基础

IBM developerworks有例子的：）
搜索MD5就可以了。

调试易

百分求购一个登陆模块--要求有MD5加密和验证码

解决方案 »