登陆时获取验证码

import lombok.extern.slf4j.Slf4j;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.security.SecureRandom;

@Slf4j
public final class CaptchaCodeUtil {

    //宽度
    private static final int CAPTCHA_WIDTH = 100;
    //高度
    private static final int CAPTCHA_HEIGHT = 35;
    //数字的长度
    private static final int NUMBER_CNT = 4;
    //图片类型
    private static final String IMAGE_TYPE = "JPEG";

    private SecureRandom r = new SecureRandom();
    // 字体: {"宋体", "华文楷体", "黑体", "华文新魏", "华文隶书", "微软雅黑", "楷体_GB2312"}
    private String[] fontNames = {"宋体", "黑体", "微软雅黑"};

    // 可选字符
    private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKMNPQRSTUVWXYZ";

    // 背景色,白色
    private Color bgColor = new Color(255, 255, 255);

    // 验证码上的文本
    private String text;

    private static CaptchaCodeUtil instance = null;

    private CaptchaCodeUtil() {
    }

    /**
     * 实例化对象
     */
    public static synchronized CaptchaCodeUtil getInstance() {
        if (instance == null) {
            instance = new CaptchaCodeUtil();
        }
        return instance;
    }

    /**
     * 创建验证码
     *
     * @param path 路径地址
     */
    public String getCode(String path) throws Exception {
        BufferedImage bi = instance.getImage();
        output(bi, new FileOutputStream(path));
        return this.text;
    }

    /**
     * 生成图片对象，并返回
     */
    public CaptchaCode getCode() throws Exception {
        BufferedImage img = instance.getImage();
        //返回验证码对象
        CaptchaCode code = new CaptchaCode();
        code.setText(this.text);
        code.setData(this.copyImage2Byte(img));
        return code;
    }

    /**
     * 将图片转化为 二进制数据
     */
    public byte[] copyImage2Byte(BufferedImage img) throws Exception {
        ByteArrayOutputStream bout = new ByteArrayOutputStream();
        ImageIO.write(img, IMAGE_TYPE, bout);
        return bout.toByteArray();
    }

    /**
     * 将二进制数据转化为文件
     */
    public boolean copyByte2File(byte[] data, String file) throws Exception {
        ByteArrayInputStream in = new ByteArrayInputStream(data);
        FileOutputStream out = new FileOutputStream(file);
        try {
            byte[] buff = new byte[1024];
            int len;
            while ((len = in.read(buff)) > -1) {
                out.write(buff, 0, len);
            }
            out.flush();
            return true;
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
            return false;
        } finally {
            out.close();
            in.close();
        }
    }

    /**
     * 生成随机的颜色
     */
    private Color randomColor() {
        int red = r.nextInt(150);
        int green = r.nextInt(150);
        int blue = r.nextInt(150);
        return new Color(red, green, blue);
    }

    /**
     * 生成随机的字体
     */
    private Font randomFont() {
        int index = r.nextInt(fontNames.length);
        String fontName = fontNames[index];// 生成随机的字体名称
        int style = r.nextInt(4);// 生成随机的样式, 0(无样式), 1(粗体), 2(斜体), 3(粗体+斜体)
        int size = r.nextInt(5) + 24; // 生成随机字号, 24 ~ 28
        return new Font(fontName, style, size);
    }

    // 画干扰线
    private void drawLine(BufferedImage image) {
        int num = 5;// 一共画5条
        Graphics2D g2 = (Graphics2D) image.getGraphics();
        for (int i = 0; i < num; i++) {// 生成两个点的坐标，即4个值
            int x1 = r.nextInt(CAPTCHA_WIDTH);
            int y1 = r.nextInt(CAPTCHA_HEIGHT);
            int x2 = r.nextInt(CAPTCHA_WIDTH);
            int y2 = r.nextInt(CAPTCHA_HEIGHT);
            g2.setStroke(new BasicStroke(1.5F));
            g2.setColor(randomColor()); // 随机生成干扰线颜色
            g2.drawLine(x1, y1, x2, y2);// 画线
        }
    }

    // 随机生成一个字符
    private char randomChar() {
        int index = r.nextInt(codes.length());
        return codes.charAt(index);
    }

    // 创建BufferedImage
    private BufferedImage createImage() {
        BufferedImage image = new BufferedImage(CAPTCHA_WIDTH, CAPTCHA_HEIGHT, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2 = (Graphics2D) image.getGraphics();
        g2.setColor(this.bgColor);
        g2.fillRect(0, 0, CAPTCHA_WIDTH, CAPTCHA_HEIGHT);
        return image;
    }

    // 调用这个方法得到验证码
    public BufferedImage getImage() {
        BufferedImage image = createImage();// 创建图片缓冲区
        Graphics2D g2 = (Graphics2D) image.getGraphics();// 得到绘制环境
        StringBuilder sb = new StringBuilder();// 用来装载生成的验证码文本
        for (int i = 0; i < NUMBER_CNT; i++) { // 循环次数，每次生成一个字符
            String s = randomChar() + "";// 随机生成一个字母
            sb.append(s); // 把字母添加到sb中
            float x = i * 1.0F * CAPTCHA_WIDTH / NUMBER_CNT; // 设置当前字符的x轴坐标
            g2.setFont(randomFont()); // 设置随机字体
            g2.setColor(randomColor()); // 设置随机颜色
            g2.drawString(s, x, CAPTCHA_HEIGHT - 5F); // 画图
        }
        this.text = sb.toString(); // 把生成的字符串赋给了this.text
        drawLine(image); // 添加干扰线
        return image;
    }

    /**
     * 返回验证码图片上的文本
     */
    public String getText() {
        return text;
    }

    // 保存图片到指定的输出流
    public static void output(BufferedImage image, OutputStream out) throws IOException {
        ImageIO.write(image, IMAGE_TYPE, out);
    }

    //图片验证码对象
    public static class CaptchaCode {
        //验证码文字信息
        private String text;
        //验证码二进制数据
        private byte[] data;

        public String getText() {
            return text;
        }

        public void setText(String text) {
            this.text = text;
        }

        public byte[] getData() {
            return data;
        }

        public void setData(byte[] data) {
            this.data = data;
        }
    }
}

@ApiModel("后台管理员登录请求参数")
@Accessors(chain = true)
@NoArgsConstructor
@Data
public class LoginRequest {

    @ApiModelProperty(value = "登录账号", dataType = "String", required = true)
    @NotBlank(message = "登录账号不能为空！")
    private String username;

    @ApiModelProperty(value = "登录密码", dataType = "String", required = true)
    @NotBlank(message = "登录密码不能为空！")
    private String password;

    @ApiModelProperty(value = "验证码", dataType = "String", required = true)
    @NotBlank(message = "验证码不能为空！")
    private String captcha;

}

@Api(tags = {"后台管理接口 - 图形验证码"})
@RequestMapping("/api")
@Slf4j
@RestController
public class CaptchaController extends BaseController {

    @GetMapping(value = {"captcha", "captcha.png"}, produces = "image/png")
    @ApiOperation(value = "获取验证码")
    public void handleRequestInternal(HttpServletResponse response)
            throws Exception {
        response.setHeader("Cache-Control", "no-cache");
        response.setContentType("image/png");
        try (OutputStream out = response.getOutputStream()) {
            CaptchaCodeUtil.CaptchaCode code = CaptchaCodeUtil.getInstance().getCode();
            String codeTxt = code.getText();
            setSessionAttr(Constants.STORE_CAPTCHA_CODE, codeTxt);
            byte[] imgs = code.getData();
            out.write(imgs, 0, imgs.length);
            out.flush();
        }
    }

}

@Api(tags = {“后台管理接口 - 登录接口”})
@Slf4j
@RestController
@RequestMapping("/api")
public class LoginController extends BaseController {

@ApiOperation(value = "登录")
@PostMapping(value = "/login")
public LoginUser login(@Valid @RequestBody LoginRequest loginRequest, BindingResult bindingResult) {
    //验证验证码
    if (bindingResult.hasErrors()) {
        FieldError fieldError = bindingResult.getFieldError();
        if(fieldError != null) {
            throw new ValidateException(fieldError.getDefaultMessage());
        }
        throw new ValidateException(StatusCode.FRIENDSHIP_ERROR);
    }
    String storeCode = getSessionAttr(Constants.STORE_CAPTCHA_CODE);
    getSession().removeAttribute(Constants.STORE_CAPTCHA_CODE);
    String captcha = loginRequest.getCaptcha().trim();
    if (!captcha.equalsIgnoreCase(storeCode)) {
        throw new BizException(StatusCode.FAIL_CODE_CAPTCHA);
    }

    LoginUser loginUser = new LoginUser();
    //todo: 登录验证
    //todo:  保存当前登录用户，返回token给前端
    return loginUser;
}

@Data
public class LoginUser {
    private String id;
    private String username;
    private String token;

    private Set<String> roles;

}