导入依赖

使用谷歌的验证码依赖

<!-- google kaptcha依赖 验证码 -->
        <dependency>
            <groupId>com.github.axet</groupId>
            <artifactId>kaptcha</artifactId>
            <version>0.0.9</version>
        </dependency>

验证码配置

验证码的工具类

@Configuration
public class CaptchaConfig { 
   @Bean
   public DefaultKaptcha getDefaultKaptcha(){ 
      //验证码生成器
      DefaultKaptcha defaultKaptcha=new DefaultKaptcha();
      //配置
      Properties properties = new Properties();
      //是否有边框
      properties.setProperty("kaptcha.border", "yes");
      //设置边框颜色
      properties.setProperty("kaptcha.border.color", "105,179,90");
      //边框粗细度，默认为1
      // properties.setProperty("kaptcha.border.thickness","1");
      //验证码
      properties.setProperty("kaptcha.session.key","code");
      //验证码文本字符颜色 默认为黑色
      properties.setProperty("kaptcha.textproducer.font.color", "blue");
      //设置字体样式
      properties.setProperty("kaptcha.textproducer.font.names", "宋体,楷体,微软雅黑");
      //字体大小，默认40
      properties.setProperty("kaptcha.textproducer.font.size", "30");
      //验证码文本字符内容范围 默认为abced2345678gfynmnpwx
      // properties.setProperty("kaptcha.textproducer.char.string", "");
      //字符长度，默认为5
      properties.setProperty("kaptcha.textproducer.char.length", "4");
      //字符间距 默认为2
      properties.setProperty("kaptcha.textproducer.char.space", "4");
      //验证码图片宽度 默认为200
      properties.setProperty("kaptcha.image.width", "100");
      //验证码图片高度 默认为40
      properties.setProperty("kaptcha.image.height", "40");
      Config config = new Config(properties);
      defaultKaptcha.setConfig(config);
      return defaultKaptcha;
   }
}

配置对应验证码请求

加了 produces = “image/jpeg” 可以使得在postman等工具中也能显示对应的验证码图片

@Autowired
    private DefaultKaptcha defaultKaptcha;//需要注入验证码生成的工具
    @GetMapping(value = "/captcha", produces = "image/jpeg")
    public void captcha(HttpServletRequest request, HttpServletResponse response) { 
        // 定义response输出类型为image/jpeg类型
        response.setDateHeader("Expires", 0);
        // Set standard HTTP/1.1 no-cache headers.
        response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        // Set IE extended HTTP/1.1 no-cache headers (use addHeader).
        response.addHeader("Cache-Control", "post-check=0, pre-check=0");
        // Set standard HTTP/1.0 no-cache header.
        response.setHeader("Pragma", "no-cache");
        // return a jpeg
        response.setContentType("image/jpeg");
        //-------------------生成验证码 begin --------------------------
        String text = defaultKaptcha.createText();
        System.out.println("验证码为:" + text);
        //将验证码放入session中
        request.getSession().setAttribute("captcha", text);
        //根据验证码创建图片
        BufferedImage image = defaultKaptcha.createImage(text);
        ServletOutputStream outputStream = null;
        try { 
            outputStream= response.getOutputStream();
            //根据image生成jpg的图像 由outputStream输出
            ImageIO.write(image, "jpg", outputStream);
            outputStream.flush();
        } catch (IOException e) { 
            if (outputStream != null) { 
                try { 
                    outputStream.close();
                } catch (IOException ioException) { 
                    ioException.printStackTrace();
                }
            }
        }
        //-------------------生成验证码 end ----------------------------
    }