1：首先配置pom依赖：

        <!-- 阿里云oss-->
        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
            <version>3.8.0</version>
        </dependency>
        <!-- 腾讯云cos-->
        <dependency>
            <groupId>com.qcloud</groupId>
            <artifactId>cos_api</artifactId>
            <version>5.6.75</version>
        </dependency>

2：application.yml:

# 上传模式 (本地 阿里云 腾讯云)
# 上传模式 (Window服务器，Linux服务器本地 阿里云 腾讯云)
upload:
  mode: windowsLocal
  linuxLocal:
    # nginx映射本地文件路径，无域名则为 ip:83
    url: https://上传子域名/
    # 本地文件存储路径
    path: /usr/local/blog/upload/
    # Windows环境下测试 这里路径对应config中mvc拦截器里面的路径
  windowsLocal:
    url: http://localhost:8080/upload/
    path: G:/桌面/博客/mongo-blog-master/springboot/src/main/resources/upload/
  oss:
    url: http://Bucket域名/
    endpoint: OSS配置endpoint
    accessKeyId: OSS配置accessKeyId
    accessKeySecret: OSS配置accessKeySecret
    bucketName: OSS配置bucketName
  cos:
    url: https://ftz-1307097786.cos.ap-beijing.myqcloud.com/
    region: ap-beijing
    secretId: AKIDhKqBJPN8mDWcWFm6oVBj4A2h7IF2lFUX
    secretKey: tBLekcFi27yb3IJ6i7GCzYt2ymLgtwmt
    bucketName: ftz-1307097786

2.1:腾讯云信息查看：secretId+secretKey在访问密钥里面查看

2.2：url+region+bucketName在配置管理查看

3：Windows本地，Linux本地,阿里云，腾讯云的配置:

3.1 :Windows本地配置：

（1）：首先配置application.yml：

（2***）：重点：配置登录拦截器，设置虚拟路径，因为浏览器不可以直接访问电脑资源目录文件，所以需要设置虚拟路径！否则会报错：Not allowed to load local resource；这里的路径要跟application.yml中的路径相匹配

 @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/upload/**").addResourceLocations("file:G:/桌面/博客/mongo-blog-master/springboot/src/main/resources/upload/");
    }

（3）：策略枚举层：

package com.jjhroy.blog.enums;

import lombok.AllArgsConstructor;
import lombok.Getter;

/**
 * 上传模式枚举
 *
 * @author yezhiqiu
 * @date 2021/07/28
 */
@Getter
@AllArgsConstructor
public enum UploadModeEnum {
    /**
     * oss
     */
    OSS("oss", "ossUploadStrategyImpl"),
    /**
     * Linux本地
     */
    LOCAL("linuxLocal", "localUploadStrategyImpl"),

    /**
     * Windows本地
     */
    WINDOWS("windowsLocal","windowsUploadStrategyImpl"),

    /**
     * cos
     */
    COS("cos", "cosUploadStrategyImpl");

    /**
     * 模式
     */
    private final String mode;

    /**
     * 策略
     */
    private final String strategy;

    /**
     * 获取策略
     *
     * @param mode 模式
     * @return {@link String} 搜索策略
     */
    public static String getStrategy(String mode) {
        for (UploadModeEnum value : UploadModeEnum.values()) {
            if (value.getMode().equals(mode)) {
                return value.getStrategy();
            }
        }
        return null;
    }

}

（4）：文件上传策略：

package com.jjhroy.blog.strategy.context;

import com.jjhroy.blog.enums.UploadModeEnum;
import com.jjhroy.blog.strategy.UploadStrategy;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.io.InputStream;
import java.util.Map;


/**
 * 上传策略上下文
 *
 * @author yezhiqiu
 * @date 2021/07/28
 */
@Service
public class UploadStrategyContext {
    /**
     * 上传模式
     */
    @Value("${upload.mode}")
    private String uploadMode;

    @Autowired
    private Map<String, UploadStrategy> uploadStrategyMap;

    /**
     * 执行上传策略
     *
     * @param file 文件
     * @param path 路径
     * @return {@link String} 文件地址
     */
    public String executeUploadStrategy(MultipartFile file, String path) {
        return uploadStrategyMap.get(UploadModeEnum.getStrategy(uploadMode)).uploadFile(file, path);
    }


    /**
     * 执行上传策略
     *
     * @param fileName    文件名称
     * @param inputStream 输入流
     * @param path        路径
     * @return {@link String} 文件地址
     */
    public String executeUploadStrategy(String fileName, InputStream inputStream, String path) {
        return uploadStrategyMap.get(UploadModeEnum.getStrategy(uploadMode)).uploadFile(fileName, inputStream, path);
    }

}

（5）：本地路径上传策略方法实现层：WindowsUploadStrategyImpl：

package com.jjhroy.blog.strategy.impl;

import com.jjhroy.blog.enums.FileExtEnum;
import com.jjhroy.blog.exception.BizException;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import java.io.*;
import java.nio.file.Files;
import java.util.Objects;

/**
 * @author ftz
 *
 * Windows本地上传策略
 *
 */
@Service("windowsUploadStrategyImpl")
public class WindowsUploadStrategyImpl extends AbstractUploadStrategyImpl  {

    /**
     * 本地路径
     */
    @Value("${upload.windowsLocal.path}")
    private String localPath;

    @Value("${upload.windowsLocal.url}")
    private String localUrl;

    @Override
    public Boolean exists(String filePath) {
        return new File(localPath + filePath).exists();
    }

    @Override
    public void upload(String path, String fileName, InputStream inputStream) throws IOException {
        // 判断目录是否存在
        File directory = new File(localPath + path);
        if (!directory.exists()) {
            if (!directory.mkdirs()) {
                throw new BizException("创建目录失败");
            }
        }
        // 写入文件
        File file = new File(localPath + path + fileName);
        String ext = "." + fileName.split("\\.")[1];
        switch (Objects.requireNonNull(FileExtEnum.getFileExt(ext))) {
            case MD:
            case TXT:
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
                BufferedWriter writer = new BufferedWriter(new FileWriter(file));
                while (reader.ready()) {
                    writer.write((char) reader.read());
                }
                writer.flush();
                writer.close();
                reader.close();
                break;
            default:
                BufferedInputStream bis = new BufferedInputStream(inputStream);
                BufferedOutputStream bos = new BufferedOutputStream(Files.newOutputStream(file.toPath()));
                byte[] bytes = new byte[1024];
                int length;
                while ((length = bis.read(bytes)) != -1) {
                    bos.write(bytes, 0, length);
                }
                bos.flush();
                bos.close();
                bis.close();
                break;
        }
        inputStream.close();
    }


    @Override
    public String getFileAccessUrl(String filePath) {
        return localUrl+filePath;
    }






}

（6）：controller层：更新用户头像为例：

    /**
     * 更新用户头像
     *
     * @param file 文件
     * @return {@link Result<String>} 头像地址
     */
    @ApiOperation(value = "更新用户头像")
    @ApiImplicitParam(name = "file", value = "用户头像", required = true, dataType = "MultipartFile")
    @PostMapping("/users/avatar")
    public Result<String> updateUserAvatar(MultipartFile file) {
        return Result.ok(userInfoService.updateUserAvatar(file));
    }

（7）：userInfoService.updateUserAvatar层及其实现：

    @Transactional(rollbackFor = Exception.class)
    @Override
    public String updateUserAvatar(MultipartFile file) {
        // 头像上传
        String avatar = uploadStrategyContext.executeUploadStrategy(file, FilePathEnum.AVATAR.getPath());
        // 更新用户信息
        UserInfo userInfo = UserInfo.builder()
                .id(UserUtils.getLoginUser().getUserInfoId())
                .avatar(avatar)
                .build();
        userInfoDao.updateById(userInfo);
        return avatar;
    }

（8）：uploadStrategyContext.executeUploadStrategy:

package com.jjhroy.blog.strategy.context;

import com.jjhroy.blog.enums.UploadModeEnum;
import com.jjhroy.blog.strategy.UploadStrategy;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.io.InputStream;
import java.util.Map;


/**
 * 上传策略上下文
 *
 * @author yezhiqiu
 * @date 2021/07/28
 */
@Service
public class UploadStrategyContext {
    /**
     * 上传模式
     */
    @Value("${upload.mode}")
    private String uploadMode;

    @Autowired
    private Map<String, UploadStrategy> uploadStrategyMap;

    /**
     * 执行上传策略
     *
     * @param file 文件
     * @param path 路径
     * @return {@link String} 文件地址
     */
    public String executeUploadStrategy(MultipartFile file, String path) {
        return uploadStrategyMap.get(UploadModeEnum.getStrategy(uploadMode)).uploadFile(file, path);
    }


    /**
     * 执行上传策略
     *
     * @param fileName    文件名称
     * @param inputStream 输入流
     * @param path        路径
     * @return {@link String} 文件地址
     */
    public String executeUploadStrategy(String fileName, InputStream inputStream, String path) {
        return uploadStrategyMap.get(UploadModeEnum.getStrategy(uploadMode)).uploadFile(fileName, inputStream, path);
    }

}

(9):抽象上传模板

（10）文件上传工具类：

package com.jjhroy.blog.util;

import com.baomidou.mybatisplus.core.toolkit.StringUtils;
import lombok.extern.log4j.Log4j2;
import org.apache.commons.codec.binary.Hex;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;
import java.util.Objects;

/**
 * 文件md5工具类
 *
 * @author yezhiqiu
 * @date 2021/07/28
 */
@Log4j2
public class FileUtils {

    /**
     * 获取文件md5值
     *
     * @param inputStream 文件输入流
     * @return {@link String} 文件md5值
     */
    public static String getMd5(InputStream inputStream) {
        try {
            MessageDigest md5 = MessageDigest.getInstance("md5");
            byte[] buffer = new byte[8192];
            int length;
            while ((length = inputStream.read(buffer)) != -1) {
                md5.update(buffer, 0, length);
            }
            return new String(Hex.encodeHex(md5.digest()));
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } finally {
            try {
                if (inputStream != null) {
                    inputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 得到文件扩展名
     *
     * @param fileName 文件名称
     * @return {@link String} 文件后缀
     */
    public static String getExtName(String fileName) {
        if (StringUtils.isBlank(fileName)) {
            return "";
        }
        return fileName.substring(fileName.lastIndexOf("."));
    }

    /**
     * 转换file
     *
     * @param multipartFile 多部分文件
     * @return {@link File} file
     */
    public static File multipartFileToFile(MultipartFile multipartFile) {
        File file = null;
        try {
            String originalFilename = multipartFile.getOriginalFilename();
            String[] filename = Objects.requireNonNull(originalFilename).split("\\.");
            file = File.createTempFile(filename[0], filename[1]);
            multipartFile.transferTo(file);
            file.deleteOnExit();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return file;
    }


    /**
     * 自动调节精度(经验数值)
     *
     * @param size 源图片大小
     * @return 图片压缩质量比
     */
    private static double getAccuracy(long size) {
        double accuracy;
        if (size < 900) {
            accuracy = 0.85;
        } else if (size < 2048) {
            accuracy = 0.6;
        } else if (size < 3072) {
            accuracy = 0.44;
        } else {
            accuracy = 0.4;
        }
        return accuracy;
    }

}

3.2：其余三种类似，只需要改变一下application.yml就好