Java 生成验证码图片

 生成验证码图片并对提交的输入进行验证

public class AuthCodeController {
    @GetMapping(value = WebSecurityConfig.URL_AUTH_CODE)
    public void getAuthCodeImg(HttpServletRequest request, HttpServletResponse response) throws IOException {

        {// 不是登录页过来的请求则直接重定向到登录页 TODO
            // String indexPageDomain = "172.20.6.11";
            String indexPageDomain = "sensestudy.sensetime.com";
            String refererStr = request.getHeader("referer");
            if (refererStr == null || !refererStr.contains(indexPageDomain)) {
                // response.sendRedirect("/baidu");
            }
        }

        Res res = AuthCodeFactory.generateAuthCode(BaseCharset.NUM_LETTER);
        // 设置响应图片格式
        response.setContentType("image/jpeg");
        // 设置响应头控制浏览器不要缓存
        response.setDateHeader("expries", -1);
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Pragma", "no-cache");

        // 将图片写给浏览器
        ImageIO.write(res.getBufferedImage(), "jpg", response.getOutputStream());
        System.out.println(res.getAuthCode());
    }
}

class AuthCodeFactory {
    private static int WIDTH = 120;// 生成的图片的宽度
    private static int HEIGHT = 30;// 生成的图片的高度

    /** 设置图片的背景色 */
    private static void setBackGround(Graphics g) {
        // 设置颜色
        g.setColor(Color.PINK);
        // 填充区域
        g.fillRect(0, 0, WIDTH, HEIGHT);
    }

    /** 设置图片的边框 */
    private static void setBorder(Graphics g) {
        // 设置边框颜色
        g.setColor(Color.BLUE);
        // 边框区域
        g.drawRect(1, 1, WIDTH - 2, HEIGHT - 2);
    }

    /** 在图片上画随机线条 */
    private static void drasRandomLine(Graphics g) {
        // 设置颜色
        g.setColor(Color.GREEN);
        // 设置线条个数并画线
        for (int i = 0; i < 5; i++) {
            int x1 = new Random().nextInt(WIDTH);
            int y1 = new Random().nextInt(HEIGHT);
            int x2 = new Random().nextInt(WIDTH);
            int y2 = new Random().nextInt(HEIGHT);
            g.drawLine(x1, y1, x2, y2);
        }
    }

    /** 画随机验证码内容 */
    private static String drawRandomAuthcode(Graphics2D g, String baseStr) {
        // 设置颜色
        g.setColor(Color.RED);
        // 设置字体
        g.setFont(new Font("宋体", Font.BOLD, 20));

        StringBuffer sb = new StringBuffer();
        int x = 5;
        String ch = "";
        // 控制字数
        for (int i = 0; i < 4; i++) {
            // 设置字体旋转角度
            int degree = new Random().nextInt() % 30;
            ch = baseStr.charAt(new Random().nextInt(baseStr.length())) + "";
            sb.append(ch);
            // 正向角度
            g.rotate(degree * Math.PI / 180, x, 20);
            g.drawString(ch, x, 20);
            // 反向角度
            g.rotate(-degree * Math.PI / 180, x, 20);
            x += 30;
        }
        return sb.toString();
    }

    public static enum BaseCharset {
        LETTER("ABCDEFGHJKLMNOPQRSTUVWXYZ"), NUMBER("0123456789"), NUM_LETTER(
                "0123456789ABCDEFGHJKLMNOPQRSTUVWXYZ"), CHNCHARSET(
                        "\"\\u7684\\u4e00\\u4e86\\u662f\\u6211\\u4e0d\\u5728\\u4eba\\u4eec\\u6709\\u6765\\u4ed6\\u8fd9\\u4e0a\\u7740\\u4e2a\\u5730\\u5230\\u5927\\u91cc\\u8bf4\\u5c31\\u53bb\\u5b50\\u5f97\\u4e5f\\u548c\\u90a3\\u8981\\u4e0b\\u770b\\u5929\\u65f6\\u8fc7\\u51fa\\u5c0f\\u4e48\\u8d77\\u4f60\\u90fd\\u628a\\u597d\\u8fd8\\u591a\\u6ca1\\u4e3a\\u53c8\\u53ef\\u5bb6\\u5b66\\u53ea\\u4ee5\\u4e3b\\u4f1a\\u6837\\u5e74\\u60f3\\u751f\\u540c\\u8001\\u4e2d\\u5341\\u4ece\\u81ea\\u9762\\u524d\\u5934\\u9053\\u5b83\\u540e\\u7136\\u8d70\\u5f88\\u50cf\\u89c1\\u4e24\\u7528\\u5979\\u56fd\\u52a8\\u8fdb\\u6210\\u56de\\u4ec0\\u8fb9\\u4f5c\\u5bf9\\u5f00\\u800c\\u5df1\\u4e9b\\u73b0\\u5c71\\u6c11\\u5019\\u7ecf\\u53d1\\u5de5\\u5411\\u4e8b\\u547d\\u7ed9\\u957f\\u6c34\\u51e0\\u4e49\\u4e09\\u58f0\\u4e8e\\u9ad8\\u624b\\u77e5\\u7406\\u773c\\u5fd7\\u70b9\\u5fc3\\u6218\\u4e8c\\u95ee\\u4f46\\u8eab\\u65b9\\u5b9e\\u5403\\u505a\\u53eb\\u5f53\\u4f4f\\u542c\\u9769\\u6253\\u5462\\u771f\\u5168\\u624d\\u56db\\u5df2\\u6240\\u654c\\u4e4b\\u6700\\u5149\\u4ea7\\u60c5\\u8def\\u5206\\u603b\\u6761\\u767d\\u8bdd\\u4e1c\\u5e2d\\u6b21\\u4eb2\\u5982\\u88ab\\u82b1\\u53e3\\u653e\\u513f\\u5e38\\u6c14\\u4e94\\u7b2c\\u4f7f\\u5199\\u519b\\u5427\\u6587\\u8fd0\\u518d\\u679c\\u600e\\u5b9a\\u8bb8\\u5feb\\u660e\\u884c\\u56e0\\u522b\\u98de\\u5916\\u6811\\u7269\\u6d3b\\u90e8\\u95e8\\u65e0\\u5f80\\u8239\\u671b\\u65b0\\u5e26\\u961f\\u5148\\u529b\\u5b8c\\u5374\\u7ad9\\u4ee3\\u5458\\u673a\\u66f4\\u4e5d\\u60a8\\u6bcf\\u98ce\\u7ea7\\u8ddf\\u7b11\\u554a\\u5b69\\u4e07\\u5c11\\u76f4\\u610f\\u591c\\u6bd4\\u9636\\u8fde\\u8f66\\u91cd\\u4fbf\\u6597\\u9a6c\\u54ea\\u5316\\u592a\\u6307\\u53d8\\u793e\\u4f3c\\u58eb\\u8005\\u5e72\\u77f3\\u6ee1\\u65e5\\u51b3\\u767e\\u539f\\u62ff\\u7fa4\\u7a76\\u5404\\u516d\\u672c\\u601d\\u89e3\\u7acb\\u6cb3\\u6751\\u516b\\u96be\\u65e9\\u8bba\\u5417\\u6839\\u5171\\u8ba9\\u76f8\\u7814\\u4eca\\u5176\\u4e66\\u5750\\u63a5\\u5e94\\u5173\\u4fe1\\u89c9\\u6b65\\u53cd\\u5904\\u8bb0\\u5c06\\u5343\\u627e\\u4e89\\u9886\\u6216\\u5e08\\u7ed3\\u5757\\u8dd1\\u8c01\\u8349\\u8d8a\\u5b57\\u52a0\\u811a\\u7d27\\u7231\\u7b49\\u4e60\\u9635\\u6015\\u6708\\u9752\\u534a\\u706b\\u6cd5\\u9898\\u5efa\\u8d76\\u4f4d\\u5531\\u6d77\\u4e03\\u5973\\u4efb\\u4ef6\\u611f\\u51c6\\u5f20\\u56e2\\u5c4b\\u79bb\\u8272\\u8138\\u7247\\u79d1\\u5012\\u775b\\u5229\\u4e16\\u521a\\u4e14\\u7531\\u9001\\u5207\\u661f\\u5bfc\\u665a\\u8868\\u591f\\u6574\\u8ba4\\u54cd\\u96ea\\u6d41\\u672a\\u573a\\u8be5\\u5e76\\u5e95\\u6df1\\u523b\\u5e73\\u4f1f\\u5fd9\\u63d0\\u786e\\u8fd1\\u4eae\\u8f7b\\u8bb2\\u519c\\u53e4\\u9ed1\\u544a\\u754c\\u62c9\\u540d\\u5440\\u571f\\u6e05\\u9633\\u7167\\u529e\\u53f2\\u6539\\u5386\\u8f6c\\u753b\\u9020\\u5634\\u6b64\\u6cbb\\u5317\\u5fc5\\u670d\\u96e8\\u7a7f\\u5185\\u8bc6\\u9a8c\\u4f20\\u4e1a\\u83dc\\u722c\\u7761\\u5174\\u5f62\\u91cf\\u54b1\\u89c2\\u82e6\\u4f53\\u4f17\\u901a\\u51b2\\u5408\\u7834\\u53cb\\u5ea6\\u672f\\u996d\\u516c\\u65c1\\u623f\\u6781\\u5357\\u67aa\\u8bfb\\u6c99\\u5c81\\u7ebf\\u91ce\\u575a\\u7a7a\\u6536\\u7b97\\u81f3\\u653f\\u57ce\\u52b3\\u843d\\u94b1\\u7279\\u56f4\\u5f1f\\u80dc\\u6559\\u70ed\\u5c55\\u5305\\u6b4c\\u7c7b\\u6e10\\u5f3a\\u6570\\u4e61\\u547c\\u6027\\u97f3\\u7b54\\u54e5\\u9645\\u65e7\\u795e\\u5ea7\\u7ae0\\u5e2e\\u5566\\u53d7\\u7cfb\\u4ee4\\u8df3\\u975e\\u4f55\\u725b\\u53d6\\u5165\\u5cb8\\u6562\\u6389\\u5ffd\\u79cd\\u88c5\\u9876\\u6025\\u6797\\u505c\\u606f\\u53e5\\u533a\\u8863\\u822c\\u62a5\\u53f6\\u538b\\u6162\\u53d4\\u80cc\\u7ec6\"");
        private String str;

        private BaseCharset(String str) {
            this.str = str;
        }

        private String getStr() {
            return this.str;
        }

    }

    public static Res generateAuthCode(BaseCharset baseCharset) {

        BufferedImage bi = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
        // 得到图片
        Graphics g = bi.getGraphics();
        // 画图
        setBackGround(g);
        setBorder(g);
        drasRandomLine(g);
        String randomAuthCode = drawRandomAuthcode((Graphics2D) g, baseCharset.getStr());

        return new Res(bi, randomAuthCode);
    }

    public static class Res {
        private BufferedImage bufferedImage;
        private String authCode;

        public Res(BufferedImage img, String authCode) {
            this.bufferedImage = img;
            this.authCode = authCode;
        }

        public BufferedImage getBufferedImage() {
            return bufferedImage;
        }

        public void setBufferedImage(BufferedImage bufferedImage) {
            this.bufferedImage = bufferedImage;
        }

        public String getAuthCode() {
            return authCode;
        }

        public void setAuthCode(String authCode) {
            this.authCode = authCode;
        }
    }
}