生成图片验证码

如标题,下面上java代码,粘贴复制即可用

  /**
     * 生成图片验证码
     * @param request
     * @param response
     */
    @RequestMapping(value = "/createCode", method = RequestMethod.GET)
    public void createCode(HttpServletRequest request,HttpServletResponse response) 
    {
    //    HttpSession session = request.getSession();
        response.setHeader("Pragma", "No-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("P3P", "CP=CAO PSA OUR");
        response.setDateHeader("Expires", 0);
        
        CheckCodeImage imageCode = new CheckCodeImage();
        try {
            ImageIO.write(imageCode.creatImage(), "JPEG",response.getOutputStream());
        } catch (IOException e) {
            logger.error("生成验证码异常",e);
        }
        
        request.getSession().setAttribute("CheckCode", imageCode.getSRand());
        
        System.out.println("###验证码:"+imageCode.getSRand());
        logger.info("###验证码:" + imageCode.getSRand());
    }

package com.ulic.gis.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;

/** 
 * 图片验证码对象
 */
public class CheckCodeImage {

    private String sRand = "";

    /**
     * 生成随机背景条纹
     */
    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);
    }

    public BufferedImage creatImage() {
        
        // 在内存中创建图象
        int width = 60;//验证码图片长度
        int height = 20;//宽
        
        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)
        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;
    }

    public String getSRand() {
        return sRand;
    }

    public void setSRand(String rand) {
        sRand = rand;
    }

}

注意需要导入正确路径,否则不能正常使用

import javax.annotation.Resource;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

html中的图片标签,注意图片的src

<img title="点击刷新" src="<%=basePath_login%>/createCode"  id="checkCodeImg" border="0" onClick="updateCheckCode()" />

少许javascript代码,用于点击刷新图片验证码

function updateCheckCode(){
    $('#checkCodeImg').attr('src','<%=request.getContextPath%>/createCode?nocache='+ new Date().getTime());
}