在struts框架中怎么应用验证码

在struts框架中如何应用验证码
我在做一个注册页面时,想应用验证码,但不知如何使用....   请教...

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去网上查一下 大把的源码 我做项目时就查用过一次. 呵呵
自己动手吧 有些东西不一定要等别人给你 自己可以查的到的
TKS 祝你成功.
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Image.jsp
<%@ page language= "java " import= "java.util.* " pageEncoding= "GBK "%>
<%@ page contentType= "image/jpeg " import= "java.awt.*,
java.awt.image.*,javax.imageio.*,java.net.* " %>



<%!
Color getRandColor(int fc,int bc){//random color
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);
}
%>
<%
//page no cache
response.setHeader( "Pragma ", "No-cache ");
response.setHeader( "Cache-Control ", "no-cache ");
response.setDateHeader( "Expires ", 0);

// create image in memory
int width=60, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

// get GraphicContext
Graphics g = image.getGraphics();


Random random = new Random();

// set background
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);

//set font
g.setFont(new Font( "Times New Roman ",Font.PLAIN,18));

//set border
//g.setColor(new Color());
//g.drawRect(0,0,width-1,height-1);

// generate confusing lines
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);
}

// 4 bit random number 随即写出4个数字
String sRand= " ";
for (int i=0;i <4;i++){
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
// put validation code to image
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
g.drawString(rand,13*i+6,16);
}

// save code to SESSION 传递图片中的数字
session.setAttribute( "rand ",sRand);


g.dispose();

// display image
ImageIO.write(image, "JPEG ", response.getOutputStream());
out.clear();
out = pageContext.pushBody();
%>


Login.jsp

<tr>
<td>
验证码：
</td>
<td>
<html:text property= "image "> </html:text>
</td>
<td>
<img width= "60 " height= "20 " src= " <%=basePath%> /image.jsp ">
</td>
</tr>


loginAction
String validatecode=(String)session.getAttribute( "rand ");