spring boot获取不了验证码

为什么还是不能获取验证码啊

package com.example.demo.utils;

import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;

/**
 * @project: ssm_sms
 * @description: 绘制验证码图片
 */
public class CreateVerifiCodeImage {

    private static int WIDTH = 90;
    private static int HEIGHT = 35;
    //字符大小
    private static int FONT_SIZE = 20;
    //验证码
    private static char[] verifiCode;
    //验证码图片
    private static BufferedImage verifiCodeImage;

    /**
     * @description: 获取验证码图片
     * @param: no
     * @return: java.awt.image.BufferedImage
     */
    public static BufferedImage getVerifiCodeImage() {
        // create a image
        verifiCodeImage = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_BGR);
        Graphics graphics = verifiCodeImage.getGraphics();

        verifiCode = generateCheckCode();
        drawBackground(graphics);
        drawRands(graphics, verifiCode);

        graphics.dispose();

        return verifiCodeImage;
    }

    /**
     * @description: 获取验证码
     * @param: no
     * @return: char[]
     */
    public static char[] getVerifiCode() {
        return verifiCode;
    }

    /**
     * @description: 随机生成验证码
     * @param: no
     * @return: char[]
     */
    private static char[] generateCheckCode() {
        String chars = "0123456789abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        char[] rands = new char[4];
        for (int i = 0; i < 4; i++) {
            int rand = (int) (Math.random() * (10 + 26 * 2));
            rands[i] = chars.charAt(rand);
        }
        return rands;
    }

    /**
     * @description: 绘制验证码
     * @param: g
     * @param: rands
     * @return: void
     */
    private static void drawRands(Graphics g, char[] rands) {
        g.setFont(new Font("Console", Font.BOLD, FONT_SIZE));

        for (int i = 0; i < rands.length; i++) {

            g.setColor(getRandomColor());
            g.drawString("" + rands[i], i * FONT_SIZE + 10, 25);
        }
    }

    /**
     * @description: 绘制验证码图片背景
     * @param: g
     * @return: void
     */
    private static void drawBackground(Graphics g) {

        g.setColor(Color.white);
        g.fillRect(0, 0, WIDTH, HEIGHT);

        // 绘制验证码干扰点
        for (int i = 0; i < 200; i++) {
            int x = (int) (Math.random() * WIDTH);
            int y = (int) (Math.random() * HEIGHT);
            g.setColor(getRandomColor());
            g.drawOval(x, y, 1, 1);

        }
    }


    /**
     * @description: 获取随机颜色
     * @param: no
     * @return: java.awt.Color
     */
    private static Color getRandomColor() {
        Random ran = new Random();
        return new Color(ran.nextInt(220), ran.nextInt(220), ran.nextInt(220));
    }
}

package com.atguigu.campu.controller;


import com.example.demo.utils.CreateVerifiCodeImage;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.image.BufferedImage;
import java.io.IOException;

@RestController
@RequestMapping("/sms/system")
public class SystemController {
    /**
     * 获取验证码图片返回给浏览器
     * @param session
     * @param response
     * @throws IOException
     */


    @RequestMapping("/getVerifiCodeImage")
    public void getVerifiCodeImage(HttpSession session, HttpServletResponse response) throws IOException {
        //使用工具类CreateVerifiCodeImage 获取验证码图片
        BufferedImage verifiCodeImage = CreateVerifiCodeImage.getVerifiCodeImage();
        //获取一下验证码图片中的值
        String Code = new String(CreateVerifiCodeImage.getVerifiCode());
        //将验证码中的值保存到session域中   用于登录时校验验证码

        session.setAttribute("Code",Code);
        //将验证码图片返回给浏览器
        ImageIO.write(verifiCodeImage,"JPG",response.getOutputStream());

    }

404，请求地址不存在，是你的请求路径不对。有配置contextpath吗？有的话路径中加上，或者不配置contextpath。

• 帮你找了个相似的问题, 你可以看下: https://ask.csdn.net/questions/7437718
• 你也可以参考下这篇文章：springboot封装全局业务异常
• 除此之外, 这篇博客: springboot项目修改个人头像中的 2.文件上传工具类 部分也许能够解决你的问题, 你可以仔细阅读以下内容或跳转源博客中阅读:
  

• 
  /**
   * 文件上传工具类
   * 
   * @author ruoyi
   */
  public class FileUploadUtils
  {
      /**
       * 默认大小 50M
       */
      public static final long DEFAULT_MAX_SIZE = 50 * 1024 * 1024;
  
      /**
       * 默认的文件名最大长度 100
       */
      public static final int DEFAULT_FILE_NAME_LENGTH = 100;
  
      /**
       * 默认上传的地址
       */
      private static String defaultBaseDir = RuoYiConfig.getProfile();
  
      public static void setDefaultBaseDir(String defaultBaseDir)
      {
          FileUploadUtils.defaultBaseDir = defaultBaseDir;
      }
  
      public static String getDefaultBaseDir()
      {
          return defaultBaseDir;
      }
  
      /**
       * 以默认配置进行文件上传
       *
       * @param file 上传的文件
       * @return 文件名称
       * @throws Exception
       */
      public static final String upload(MultipartFile file) throws IOException
      {
          try
          {
              return upload(getDefaultBaseDir(), file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
          }
          catch (Exception e)
          {
              throw new IOException(e.getMessage(), e);
          }
      }
  
      /**
       * 根据文件路径上传
       *
       * @param baseDir 相对应用的基目录
       * @param file 上传的文件
       * @return 文件名称
       * @throws IOException
       */
      public static final String upload(String baseDir, MultipartFile file) throws IOException
      {
          try
          {
              return upload(baseDir, file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
          }
          catch (Exception e)
          {
              throw new IOException(e.getMessage(), e);
          }
      }
  
      /**
       * 文件上传
       *
       * @param baseDir 相对应用的基目录
       * @param file 上传的文件
       * @param allowedExtension 上传文件类型
       * @return 返回上传成功的文件名
       * @throws FileSizeLimitExceededException 如果超出最大大小
       * @throws FileNameLengthLimitExceededException 文件名太长
       * @throws IOException 比如读写文件出错时
       * @throws InvalidExtensionException 文件校验异常
       */
      public static final String upload(String baseDir, MultipartFile file, String[] allowedExtension)
              throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException,
              InvalidExtensionException
      {
          int fileNamelength = file.getOriginalFilename().length();
          if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH)
          {
              throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
          }
  
          assertAllowed(file, allowedExtension);
  
          String fileName = extractFilename(file);
  
          File desc = getAbsoluteFile(baseDir, fileName);
          file.transferTo(desc);
          String pathFileName = getPathFileName(baseDir, fileName);
          return pathFileName;
      }
  
      /**
       * 编码文件名
       */
      public static final String extractFilename(MultipartFile file)
      {
          String fileName = file.getOriginalFilename();
          String extension = getExtension(file);
          fileName = DateUtils.datePath() + "/" + IdUtils.fastUUID() + "." + extension;
          return fileName;
      }
  
      public static final File getAbsoluteFile(String uploadDir, String fileName) throws IOException
      {
          File desc = new File(uploadDir + File.separator + fileName);
  
          if (!desc.exists())
          {
              if (!desc.getParentFile().exists())
              {
                  desc.getParentFile().mkdirs();
              }
          }
          return desc;
      }
  
      public static final String getPathFileName(String uploadDir, String fileName) throws IOException
      {
          int dirLastIndex = RuoYiConfig.getProfile().length() + 1;
          String currentDir = StringUtils.substring(uploadDir, dirLastIndex);
          String pathFileName = Constants.RESOURCE_PREFIX + "/" + currentDir + "/" + fileName;
          return pathFileName;
      }
  
      /**
       * 文件大小校验
       *
       * @param file 上传的文件
       * @return
       * @throws FileSizeLimitExceededException 如果超出最大大小
       * @throws InvalidExtensionException
       */
      public static final void assertAllowed(MultipartFile file, String[] allowedExtension)
              throws FileSizeLimitExceededException, InvalidExtensionException
      {
          long size = file.getSize();
          if (DEFAULT_MAX_SIZE != -1 && size > DEFAULT_MAX_SIZE)
          {
              throw new FileSizeLimitExceededException(DEFAULT_MAX_SIZE / 1024 / 1024);
          }
  
          String fileName = file.getOriginalFilename();
          String extension = getExtension(file);
          if (allowedExtension != null && !isAllowedExtension(extension, allowedExtension))
          {
              if (allowedExtension == MimeTypeUtils.IMAGE_EXTENSION)
              {
                  throw new InvalidExtensionException.InvalidImageExtensionException(allowedExtension, extension,
                          fileName);
              }
              else if (allowedExtension == MimeTypeUtils.FLASH_EXTENSION)
              {
                  throw new InvalidExtensionException.InvalidFlashExtensionException(allowedExtension, extension,
                          fileName);
              }
              else if (allowedExtension == MimeTypeUtils.MEDIA_EXTENSION)
              {
                  throw new InvalidExtensionException.InvalidMediaExtensionException(allowedExtension, extension,
                          fileName);
              }
              else if (allowedExtension == MimeTypeUtils.VIDEO_EXTENSION)
              {
                  throw new InvalidExtensionException.InvalidVideoExtensionException(allowedExtension, extension,
                          fileName);
              }
              else
              {
                  throw new InvalidExtensionException(allowedExtension, extension, fileName);
              }
          }
      }
  
      /**
       * 判断MIME类型是否是允许的MIME类型
       *
       * @param extension
       * @param allowedExtension
       * @return
       */
      public static final boolean isAllowedExtension(String extension, String[] allowedExtension)
      {
          for (String str : allowedExtension)
          {
              if (str.equalsIgnoreCase(extension))
              {
                  return true;
              }
          }
          return false;
      }
  
      /**
       * 获取文件名的后缀
       * 
       * @param file 表单文件
       * @return 后缀名
       */
      public static final String getExtension(MultipartFile file)
      {
          String extension = FilenameUtils.getExtension(file.getOriginalFilename());
          if (StringUtils.isEmpty(extension))
          {
              extension = MimeTypeUtils.getExtension(file.getContentType());
          }
          return extension;
      }
  }
  

• 您还可以看一下 王明敏老师的Spring Boot入门初体验课程中的 课程简介小节, 巩固相关知识点