maven导入依赖

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.15</version>
        </dependency>
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.6</version>
        </dependency>
        <!-- 阿里云OSS -->
        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
            <version>3.10.2</version>
        </dependency>
    </dependencies>

定义阿里云上传结果实体

package com.example.demo.entity;

import lombok.Data;

/**
 * 阿里云上传结果集
 *
 * @author wushuai
 * @create 2021-01-25
 */
@Data
public class AliyunOssResult {
    /**
     * code：200成功
     * code: 400失败
     */
    private int code;

    /**
     * 上传成功的返回url
     */
    private String url;

    /**
     * 提示信息
     */
    private String msg;
}

yml设置阿里云oss参数

aliyunOss:
  endpoint: "http://oss-cn-shanghai.aliyuncs.com"
  accessKeyId: "xxxxxxx"
  accessKeySecret: "xxxxxxx"
  bucketName: "xxxxxx"
  urlPrefix: "http://bucketName.oss-cn-shanghai.aliyuncs.com/"

yml设置上传文件大小限制

spring:
  servlet:
    multipart:
      max-file-size: 20MB
      max-request-size: 20MB

工具类封装

package com.example.demo.util;

import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.model.DeleteObjectsRequest;
import com.aliyun.oss.model.DeleteObjectsResult;
import com.aliyun.oss.model.GeneratePresignedUrlRequest;
import com.example.demo.entity.AliyunOssResult;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.io.InputStream;
import java.net.URL;
import java.util.Date;
import java.util.List;

@Component
public class AliyunOSSUtil {

    @Value("${aliyunOss.endpoint}")
    private String endpoint;
    @Value("${aliyunOss.accessKeyId}")
    private String accessKeyId;
    @Value("${aliyunOss.accessKeySecret}")
    private String accessKeySecret;
    @Value("${aliyunOss.bucketName}")
    private String bucketName;
    @Value("${aliyunOss.urlPrefix}")
    private String urlPrefix;

    /**
     * 上传文件，以IO流方式
     *
     * @param inputStream 输入流
     * @param objectName      唯一objectName（在oss中的文件名字）
     */
    public AliyunOssResult upload(InputStream inputStream, String objectName) {
        AliyunOssResult aliyunOssResult = new AliyunOssResult();
        try {
            // 创建OSSClient实例。
            OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
            // 上传内容到指定的存储空间（bucketName）并保存为指定的文件名称（objectName）。
            ossClient.putObject(bucketName, objectName, inputStream);
            // 关闭OSSClient。
            ossClient.shutdown();
            aliyunOssResult.setCode(200);
            aliyunOssResult.setUrl(urlPrefix+objectName);
            aliyunOssResult.setMsg("上传成功");
        } catch (Exception e) {
            e.printStackTrace();
            aliyunOssResult.setCode(400);
            aliyunOssResult.setMsg("上传失败");
        }
        return aliyunOssResult;
    }

    /**
     * 删除OSS中的单个文件
     *
     * @param objectName 唯一objectName（在oss中的文件名字）
     */
    public void delete(String objectName) {
        try {
            // 创建OSSClient实例。
            OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
            // 删除文件。
            ossClient.deleteObject(bucketName, objectName);
            // 关闭OSSClient。
            ossClient.shutdown();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 批量删除OSS中的文件
     *
     * @param objectNames oss中文件名list
     */
    public void delete(List<String> objectNames) {
        try {
            // 创建OSSClient实例。
            OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
            // 批量删除文件。
            DeleteObjectsResult deleteObjectsResult = ossClient.deleteObjects(new DeleteObjectsRequest(bucketName).withKeys(objectNames));
            List<String> deletedObjects = deleteObjectsResult.getDeletedObjects();
            // 关闭OSSClient。
            ossClient.shutdown();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取文件临时url
     *
     * @param objectName oss中的文件名
     * @param effectiveTime 有效时间(ms)
     */
    public String getUrl(String objectName,long effectiveTime){
        OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
        // 设置URL过期时间
        Date expiration = new Date(new Date().getTime() + effectiveTime);
        GeneratePresignedUrlRequest generatePresignedUrlRequest ;
        generatePresignedUrlRequest =new GeneratePresignedUrlRequest(bucketName, objectName);
        generatePresignedUrlRequest.setExpiration(expiration);
        URL url = ossClient.generatePresignedUrl(generatePresignedUrlRequest);
        return url.toString();
    }

}

controller接收调用

package com.example.demo.controller;

import com.example.demo.util.AliyunOSSUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/file")
public class FileController {

    @Autowired
    private AliyunOSSUtil aliyunOSSUtil;

    @RequestMapping(value = "/uploadFile")
    public @ResponseBody
    Object uploadFile(@RequestParam(value = "file", required = false) MultipartFile file,
                      String strPath) throws IOException {
        String suffix = file.getOriginalFilename().substring(file.getOriginalFilename().lastIndexOf(".") + 1);
        String objectName = strPath+"/"+ UUID.randomUUID().toString()+"."+suffix;
        return aliyunOSSUtil.upload(file.getInputStream(),objectName);
    }
}

postman测试