一个Java类：

package com.abc.ufo.util;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.io.OutputStream;import java.util.Random;import javax.imageio.ImageIO;public class ImageMaker{    private char map[]={'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','1','2','3','4','5','6','7','8','9'};    public String getImage(int width,int height,OutputStream os){        BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);                Graphics g=image.getGraphics();        g.setColor(new Color(0xDCDCDC));        g.fillRect(0, 0, width, height);                                StringBuilder sb=new StringBuilder();        for(int i=0;i<4;i++){            sb.append(map[(int)(map.length*Math.random())]);        }        String text=sb.toString();                g.setColor(Color.black);        g.setFont(new Font("Arial",Font.PLAIN,36));                g.setColor(Color.red);        String str=text.substring(0,1);        g.drawString(str, 18, 32);                g.setColor(Color.blue);        str=text.substring(1,2);        g.drawString(str, 60, 32);                g.setColor(Color.red);        str=text.substring(2,3);        g.drawString(str, 95, 32);                g.setColor(Color.blue);        str=text.substring(3,4);        g.drawString(str, 125, 32);                g.setColor(Color.gray);        Random rand=new Random();        for(int i=0;i<20;i++){            int x=rand.nextInt(width);            int y=rand.nextInt(height);            g.drawOval(x, y, width, height);        }                g.setColor(Color.black);        g.drawRect(0, 0, width-1, height-1);        //g.drawLine(width-2, 0, width-2, height);                g.dispose();                try{            ImageIO.write(image, "JPEG", os);        }catch(Exception e){            //e.printStackTrace();        }                return text;    }}

JSP：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%@ page contentType="image/jpeg" %>
     <%    String str=image.getImage(160,40,response.getOutputStream());    session.setAttribute("verifyCode",str);    out.clear();      out = pageContext.pushBody(); %>

页面使用：

     
            
                       
       
        
            
                                          
      
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No Zero in the verification code
                
        
                       
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页面效果：