求:jsp+javabean登陆应验代码

求:jsp+javabean登陆验证代码
如图.谢谢大家

------解决方案--------------------
Javabean文件：Image.java
package javabean;

import java.awt.*;
import java.awt.image.*;
import java.util.*;

public class Image {

public String sRand= " ";

public 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);
}
public BufferedImage creatImage(){

// 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( ". "));

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);
}
// 图象生效
g.dispose();
return image;
}
}

Image.jsp
<%@ page contentType= "image/jpeg " import= "java.awt.*,
java.awt.image.*,java.util.*,javax.imageio.* " %>
<%!
Color getRandColor(int fc,int bc)
{
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);
}
%>
<%
response.setHeader( "Pragma ", "No-cache ");
response.setHeader( "Cache-Control ", "no-cache ");
response.setDateHeader( "Expires ", 0);

int width=60, height=20;//验证码图片的高和宽
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);//验证码的类型


Graphics g = image.getGraphics();
Random random = new Random();

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

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



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);
}


String sRand= " ";
char codeTable[]={
'a ', 'b ', 'c ', 'd ', 'e ', 'f ', 'g ', 'h ', 'i ', 'j ', 'k ', 'l ', 'm ',
'n ', 'o ', 'p ', 'q ', 'r ', 's ', 't ', 'u ', 'v ', 'w ', 'x ', 'y ', 'z ',