java输出4位网站验证码,

    private static final String AUTH_CODE = "0123456789";        public static String getCheckCode()    {        StringBuilder sb = new StringBuilder();        for(int i = 0;i<4;i++)        {            int index = new Random().nextInt(AUTH_CODE.length());            sb.append(AUTH_CODE.charAt(index));        }        return sb.toString();    }
------解决方案--------------------
1、如下是产生验证码的class，你只需要小小改一下，排除1,0,o,O,l,L,Z,2,9,g等。
Java code
import java.awt.Graphics;import java.awt.image.BufferedImage;import java.util.Random;//定义类public class VerifyCode {    static Random r = new Random();    static String ssource =  "0123456789";    static char[] src = ssource.toCharArray();            //产生随机字符串        private static String randString (int length){        char[] buf = new char[length];        int rnd;        for(int i=0;i<length;i++){            rnd = Math.abs(r.nextInt()) % src.length;                        buf[i] = src[rnd];        }        return new String(buf);    }        //调用该方法，产生随机字符串,    //参数i: 为字符串的长度    public String runVerifyCode(int i){        String VerifyCode = randString(i);        return VerifyCode;    }            //给定范围获得随机颜色    public 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);       }        //调用该方法将得到的验证码生成图象      //sCode:传递验证码 w:图象宽度 h:图象高度      public BufferedImage CreateImage(String sCode)      {          try{                  //字符的字体            Font CodeFont = new Font("Arial Black",Font.PLAIN,16);            int iLength = sCode.length();                    //得到验证码长度            int width=22*iLength, height=20;                //图象宽度与高度            int CharWidth = (int)(width-24)/iLength;        //字符距左边宽度            int CharHeight = 16;                            //字符距上边高度                        // 在内存中创建图象            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(200,240));            g.fillRect(0, 0, width, height);                        //设定字体            g.setFont(CodeFont);                        //画随机颜色的边框            g.setColor(getRandColor(10,50));            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);            }                            for (int i=0;i<iLength;i++)            {                String rand = sCode.substring(i,i+1);                 // 将认证码显示到图象中                g.setColor(new Color(20+random.nextInt(60),20+random.nextInt(120),20+random.nextInt(180)));                g.drawString(rand,CharWidth*i+14,CharHeight);            }            // 图象生效            g.dispose();            return image;        }catch(Exception e){            //e.printStackTrace();                //System.out.println(e.getMessage());            }        return null;    }        //测试    public static void main(String[] args){                //VerifyCode vc = new VerifyCode();            //String s1 = vc.runVerifyCode(4);            //Fun.DreamNewsTitle;System.out.println(s1);                //Image im = vc.CreateImage(s1);            //Graphics g = im.getGraphics();            //g.drawImage(im,20,20,this);            //g.drawString(s1,20,20);                }    }