使用uclpud对象存储存储文件，比如excel、pdf、png等，这里讲述一下完整的一套使用流程。

        官方文档说明：https://github.com/ucloud/ufile-sdk-java

        首先在ucloud对象存储中建立存储空间并设置存储空间域名:

         创建完毕后进入文件管理，创建需要的文件目录：

         然后创建令牌，令牌主要是Java调用的时候用以验证使用：

         创建完毕可以查看公钥和私钥。

        接下来进行一套流程的代码编写，包括Controller层，service层、web层：

        引入pom.xml依赖：

<dependency>
  <groupId>cn.ucloud.ufile</groupId>
  <artifactId>ufile-client-java</artifactId>
  <version>2.4.4</version>
</dependency>

        编写Controller层：

import io.swagger.annotations.ApiImplicitParam;
import io.swagger.annotations.ApiImplicitParams;
import io.swagger.annotations.ApiOperation;
import net.mingsoft.base.entity.ResultData;
import net.mingsoft.basic.action.BaseFileAction;
import net.mingsoft.basic.annotation.LogAnn;
import net.mingsoft.basic.constant.e.BusinessTypeEnum;
import net.mingsoft.cms.biz.IUcloudProviderService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@Controller("ucloudUpload")
@RequestMapping("/ucloud")
@Scope("request")
public class UcloudUploadController extends BaseFileAction{
    @Autowired
    private IUcloudProviderService ucloudProviderService;

    @ApiOperation(value = "ucloud上传文件")
    @ApiImplicitParams({
            @ApiImplicitParam(name = "request", value = "表单信息", required =true,paramType="query"),
    })
    @LogAnn(title = "上传文件", businessType = BusinessTypeEnum.UPDATE)
    @PostMapping("/upload")
    @ResponseBody
    public ResultData upload(HttpServletRequest req, HttpServletResponse res) throws IOException {
        MultipartHttpServletRequest multipartRequest =
                (MultipartHttpServletRequest)req;
        MultipartFile file = multipartRequest.getFile("file");
        String url = ucloudProviderService.upload(file.getInputStream(), file.getContentType(), file.getOriginalFilename());

        return ResultData.build().success(url);
    }

}

        Service层：

import java.io.InputStream;


public interface IUcloudProviderService {
    String upload(InputStream inputStream, String mimeType, String fileName);
}

import cn.ucloud.ufile.UfileClient;
import cn.ucloud.ufile.api.object.ObjectConfig;
import cn.ucloud.ufile.auth.ObjectAuthorization;
import cn.ucloud.ufile.auth.UfileObjectLocalAuthorization;
import cn.ucloud.ufile.bean.PutObjectResultBean;
import cn.ucloud.ufile.exception.UfileClientException;
import cn.ucloud.ufile.exception.UfileServerException;
import net.mingsoft.cms.biz.IUcloudProviderService;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import java.io.InputStream;
import java.util.UUID;


@Service
public class UcloudProviderServiceImpl implements IUcloudProviderService {
    @Value("${ucloud.ufile.publickey}")
    private String publicKey;
    @Value("${ucloud.ufile.privatekey}")
    private String privateKey;
    // bucketName指存储空间，即域名前的那个名称
    @Value("${ucloud.bucketName}")
    private String bucketName;


    public String upload(InputStream inputStream, String mimeType,String fileName){
        String newName = "";
        String[] split = fileName.split("\\.");
        if(split.length>1){
            newName =UUID.randomUUID()+"."+split[split.length-1];
        }else {
            return null;
        }

        try {
            // 这里指创建的目录
            String ServerFileName = "test-file/" + newName;
            // Bucket相关API的授权器
            ObjectAuthorization objectAuthorization = new UfileObjectLocalAuthorization(publicKey,privateKey);
            // 对象操作需要ObjectConfig来配置您的地区和域名后缀
            ObjectConfig config = new ObjectConfig("cn-sh2", "ufileos.com");
            PutObjectResultBean response = UfileClient.object(objectAuthorization, config)
                    .putObject(inputStream, mimeType)
                    .nameAs(ServerFileName)
                    .toBucket(bucketName)
                    .setOnProgressListener((bytesWritten, contentLength) -> { })
                    .execute();
            if(response!=null && response.getRetCode() == 0 ){
                String url = UfileClient.object(objectAuthorization, config)
                        .getDownloadUrlFromPrivateBucket(ServerFileName, bucketName, 24 * 60 * 60)
                        .createUrl();
                return url;
            }else {
                return "文件上传失败";
            }
        } catch (UfileClientException e) {
            e.printStackTrace();
            return null;
        } catch (UfileServerException e) {
            e.printStackTrace();
            return null;
        }
    }
}

         在yaml文件中配置ucloud令牌信息：

ucloud:
  bucketName: test
  ufile:
    publickey: xxxxxxxxxxxxxxxxxxxx
    privatekey: xxxxxxxxxxxxxx

        web层：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<h4>ucloud上传</h4>
<form action="/ucloud/upload" method="post" enctype="multipart/form-data">
    <p><input type="file" name="file"></p>
    <p><input type="submit" value="提交"></p>
</form>

</body>
</html>