[技术笔记] 【成都校区】java生成图片验证码

最近在用ssm框架做一个管理系统，做到登录验证时，使用了下面的代码生成图片验证码，最终的效果如下图。

Java类

[AppleScript] 纯文本查看 复制代码

public class RandomValidateCode {
    public static final String RANDOMCODEKEY = "randomcode_key";//放到session中的key
    private Random random = new Random();
    private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生的字符串

    private int width = 80;//图片宽
    private int height = 26;//图片高
    private int lineSize = 40;//干扰线数量
    private int stringNum = 4;//随机产生字符数量

    /**
     * 生成随机图片
     */
    public void getRandcode(HttpServletRequest request,
                            HttpServletResponse response) {
        HttpSession session = request.getSession();
        //BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
        BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_BGR);
        //产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
        Graphics g = image.getGraphics();
        g.fillRect(0, 0, width, height);
        g.setFont(new Font("Times New Roman",Font.ROMAN_BASELINE,18));
        g.setColor(getRandColor(160, 200));
        //绘制干扰线
        for(int i=0;i<=lineSize;i++){
            drowLine(g);
        }
        //绘制随机字符
        String randomString = "";
        for(int i=1;i<=stringNum;i++){
            randomString=drowString(g,randomString,i);
        }
        session.removeAttribute(RANDOMCODEKEY);
        session.setAttribute(RANDOMCODEKEY, randomString);
        g.dispose();
        try {
            //将内存中的图片通过流动形式输出到客户端
            ImageIO.write(image, "JPEG", response.getOutputStream());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    /*
     * 获得字体
     */
    private Font getFont(){
        return new Font("Fixedsys",Font.CENTER_BASELINE,18);
    }
    /*
     * 获得颜色
     */
    private Color getRandColor(int fc,int bc){
        if(fc > 255)
            fc = 255;
        if(bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc-fc-16);
        int g = fc + random.nextInt(bc-fc-14);
        int b = fc + random.nextInt(bc-fc-18);
        return new Color(r,g,b);
    }

    /*
     * 绘制字符串
     */
    private String drowString(Graphics g,String randomString,int i){
        g.setFont(getFont());
        g.setColor(new Color(random.nextInt(101),random.nextInt(111),random.nextInt(121)));
        String rand = String.valueOf(getRandomString(random.nextInt(randString.length())));
        randomString +=rand;
        g.translate(random.nextInt(3), random.nextInt(3));
        g.drawString(rand, 13*i, 16);
        return randomString;
    }
    /*
     * 绘制干扰线
     */
    private void drowLine(Graphics g){
        int x = random.nextInt(width);
        int y = random.nextInt(height);
        int xl = random.nextInt(13);
        int yl = random.nextInt(15);
        g.drawLine(x, y, x+xl, y+yl);
    }
    /*
     * 获取随机的字符
     */
    public String getRandomString(int num){
        return String.valueOf(randString.charAt(num));
    }
}

Controller

[AppleScript] 纯文本查看 复制代码

 @RequestMapping(value="/checkCode")
    public void checkCode(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //设置相应类型,告诉浏览器输出的内容为图片
        response.setContentType("image/jpeg");

        //设置响应头信息，告诉浏览器不要缓存此内容
        response.setHeader("pragma", "no-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expire", 0);

        RandomValidateCode randomValidateCode = new RandomValidateCode();
        try {
            randomValidateCode.getRandcode(request, response);//输出图片方法
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

前端jsp页面表单，显示验证码

[HTML] 纯文本查看 复制代码

      <div class="layui-form-item">
                    <div class="layui-row">
                        <div class="layui-col-xs7">
                            <label class="layadmin-user-login-icon layui-icon layui-icon-vercode" for="LAY-user-login-vercode"></label>
                            <input type="text" name="code" id="LAY-user-login-vercode" lay-verify="required" placeholder="图形验证码" class="layui-input">
                        </div>
                        <div class="layui-col-xs5">
                            <div style="margin-left: 10px;">
                                <img src="${pageContext.request.contextPath}checkCode" class="layadmin-user-login-codeimg" id="LAY-user-get-vercode" alt="">
                            </div>
                        </div>
                    </div>
                </div>

帐号		自动登录	找回密码
密码			加入黑马

[技术笔记] 【成都校区】java生成图片验证码

0 个回复