登录验证码

接口

import com.**.common.lang.StringUtils; //自行引用
import com.**.common.web.BaseController;//自行引用
import com.**.modules.sys.utils.CaptchaUtils;//下面给出
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Date;
import java.util.Map;

/**
 * @Auther: 
 * @Date: 2018/11/15 14:24
 * @Description:
 */
@Controller
@RequestMapping(value = "captcha")
public class CaptchaController extends BaseController {

    @RequestMapping(value = "/getCaptcha")
    @ResponseBody
    public String imagecode(HttpServletRequest request, HttpServletResponse response) throws Exception {
        response.setDateHeader("Expires", 0);
        response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        response.addHeader("Cache-Control", "post-check=0, pre-check=0");
        response.setHeader("Pragma", "no-cache");
        response.setContentType("image/jpeg");

        OutputStream os = response.getOutputStream();
        //返回验证码和图片的map
        Map<String,Object> map = CaptchaUtils.getImageCode(86, 34, os);
        String simpleCaptcha = "simpleCaptcha";
        request.getSession().setAttribute(simpleCaptcha, map.get("strEnsure").toString().toLowerCase());
        request.getSession().setAttribute("codeTime",new Date().getTime());
        try {
            ImageIO.write((BufferedImage) map.get("image"), "jpg", os);
        } catch (IOException e) {
            return "";
        }   finally {
            if (os != null) {
                os.flush();
                os.close();
            }
        }
        return null;
    }

    @RequestMapping(value = "/verify")
    @ResponseBody
    public String checkcode(HttpServletRequest request,
                            HttpSession session,
                            String checkCode) throws Exception {
        // 获得验证码对象
        Object cko = session.getAttribute("simpleCaptcha");
//        if (cko == null) {
//            request.setAttribute("errorMsg", "请输入验证码！");
//            return "请输入验证码！";
//        }
        String captcha = cko.toString();
        // 判断验证码输入是否正确
        if (StringUtils.isEmpty(checkCode) || captcha == null || !(checkCode.equalsIgnoreCase(captcha))) {
            request.setAttribute("errorMsg", "验证码错误！");
            return "false";
        } else {
            // 在这里可以处理自己需要的事务，比如验证登陆等
            return "true";
        }
    }

}

工具类

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.OutputStream;import java.util.HashMap;
import java.util.Map;import java.util.Random;

/**
 * @Auther: 
 * @Date: 2018/11/15 14:28
 * @Description:
 */
public class CaptchaUtils {
    private static char mapTable[] = {
            '0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', '0', '1',
            '2', '3', '4', '5', '6', '7',
            '8', '9'};
    public static Map<String, Object> getImageCode(int width, int height, OutputStream os) {
        Map<String,Object> returnMap = new HashMap<String, Object>();
        if (width <= 0) width = 60;
        if (height <= 0) height = 20;
        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));
        g.setColor(getRandColor(160, 200));
//        // 随机产生168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 < 168; 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);
//        }
        // 画 50 个噪点(颜色及位置随机
        for (int i = 0; i < 50; i++) {
            // 随机颜色
            int rInt = random.nextInt(100)+50;
            int gInt = random.nextInt(100)+50;
            int bInt = random.nextInt(100)+50;
            g.setColor(new Color(rInt, gInt, bInt));
            // 随机位置
            int xInt = random.nextInt(width - 3);
            int yInt = random.nextInt(height - 2);
            // 随机旋转角度
            int sAngleInt = random.nextInt(360);
            int eAngleInt = random.nextInt(360);
            // 随机大小
            int wInt = random.nextInt(6);
            int hInt = random.nextInt(6);
            // 填充背景
            g.fillArc(xInt, yInt, wInt, hInt, sAngleInt, eAngleInt);
            // 画5条干扰线
            if (i % 10 == 0) {
                int xInt2 = random.nextInt(width);
                int yInt2 = random.nextInt(height);
                g.drawLine(xInt, yInt, xInt2, yInt2);
            }
        }
        //取随机产生的码
        String strEnsure = "";
        //4代表4位验证码,如果要生成更多位的认证码,则加大数值
        for (int i = 0; i < 4; ++i) {
            strEnsure += mapTable[(int) (mapTable.length * Math.random())];
            // 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)));
            // 直接生成
            String str = strEnsure.substring(i, i + 1);
            // 设置随便码在背景图图片上的位置
            g.drawString(str, 13 * i + 20, 25);
        }
        // 释放图形上下文
        g.dispose();
        returnMap.put("image",image);
        returnMap.put("strEnsure",strEnsure);
        return returnMap;
    }
    //给定范围获得随机颜色
    static 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);
    }
}

引用

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