上传文件到阿里云oss并下载

阿里云开通对象存储OSS

1.创建Bucket

 

 

2.创建一个目录，用于存放文件

 

 

 3.获取AccessKey ID和AccessKey Secret记录下载，后面会用到

 

 

 

 4.获取Endpoint和Bucket

 

 

 

 后端代码

1.加入maven

<!--阿里云oss-->
<dependency>
    <groupId>com.aliyun.oss</groupId>
    <artifactId>aliyun-sdk-oss</artifactId>
    <version>2.8.3</version>
</dependency>

2.创建一个AliYunOSSClientUtil工具类

public class AliYunOSSClientUtil {

    private static Logger logger = LoggerFactory.getLogger(FileUtil.class);

    private static String ENDPOINT =SystemUtil.ENDPOINT;
    private static String ACCESS_KEY_ID=SystemUtil.ACCESS_KEY_ID;
    private static String ACCESS_KEY_SECRET=SystemUtil.ACCESS_KEY_SECRET;
    private static String BACKET_NAME=SystemUtil.BACKET_NAME;
    private static String FOLDER=SystemUtil.FOLDER;
    /* //初始化属性

     /**
      * 获得阿里云OSS客户端对象
      * @return ossClient
      */
    public static OSSClient getOSSClient(){
        return new OSSClient(ENDPOINT,ACCESS_KEY_ID, ACCESS_KEY_SECRET);
    }
    /**
     * 创建存储空间
     * @param ossClient OSS连接
     * @param bucketName 存储空间
     * @return
     */
    public static String createBucketName(OSSClient ossClient,String bucketName){
        //存储空间
        final String bucketNames=bucketName;
        if(!ossClient.doesBucketExist(bucketName)){
            //创建存储空间
            Bucket bucket=ossClient.createBucket(bucketName);
            logger.info("创建存储空间成功");
            return bucket.getName();
        }
        return bucketNames;
    }

    /**
     * 删除存储空间buckName
     * @param ossClient  oss对象
     * @param bucketName  存储空间
     */
    public static  void deleteBucket(OSSClient ossClient, String bucketName){
        ossClient.deleteBucket(bucketName);
        logger.info("删除" + bucketName + "Bucket成功");
    }
    /**
     * 创建模拟文件夹
     * @param ossClient oss连接
     * @param bucketName 存储空间
     * @param folder   模拟文件夹名如"qj_nanjing/"
     * @return  文件夹名
     */
    public  static String createFolder(OSSClient ossClient,String bucketName,String folder){
        //文件夹名
        final String keySuffixWithSlash =folder;
        //判断文件夹是否存在，不存在则创建
        if(!ossClient.doesObjectExist(bucketName, keySuffixWithSlash)){
            //创建文件夹
            ossClient.putObject(bucketName, keySuffixWithSlash, new ByteArrayInputStream(new byte[0]));
            logger.info("创建文件夹成功");
            //得到文件夹名
            OSSObject object = ossClient.getObject(bucketName, keySuffixWithSlash);
            String fileDir=object.getKey();
            return fileDir;
        }
        return keySuffixWithSlash;
    }
    /**
     * 根据key删除OSS服务器上的文件
     * @param ossClient  oss连接
     * @param bucketName  存储空间
     * @param folder  模拟文件夹名 如"qj_nanjing/"
     * @param key Bucket下的文件的路径名+文件名 如："upload/cake.jpg"
     */
    public static void deleteFile(OSSClient ossClient, String bucketName, String folder, String key){
        ossClient.deleteObject(bucketName, folder + key);
        logger.info("删除" + bucketName + "下的文件" + folder + key + "成功");
    }
    /**
     * 上传图片至OSS
     * @param ossClient  oss连接
     * @param file 上传文件（文件全路径如：D:\\image\\cake.jpg）
     * @param bucketName  存储空间
     * @param folder 模拟文件夹名 如"qj_nanjing/"
     * @return String 返回的唯一MD5数字签名
     * */
    public static  String uploadObject2OSS(OSSClient ossClient, File file, String bucketName, String folder) {
        String resultStr = null;
        try {
            //以输入流的形式上传文件
            InputStream is = new FileInputStream(file);
            //文件名
            String fileName = file.getName();
            //文件大小
            Long fileSize = file.length();
            //创建上传Object的Metadata
            ObjectMetadata metadata = new ObjectMetadata();
            //上传的文件的长度
            metadata.setContentLength(is.available());
            //指定该Object被下载时的网页的缓存行为
            metadata.setCacheControl("no-cache");
            //指定该Object下设置Header
            metadata.setHeader("Pragma", "no-cache");
            //指定该Object被下载时的内容编码格式
            metadata.setContentEncoding("utf-8");
            //文件的MIME，定义文件的类型及网页编码，决定浏览器将以什么形式、什么编码读取文件。如果用户没有指定则根据Key或文件名的扩展名生成，
            //如果没有扩展名则填默认值application/octet-stream
            metadata.setContentType(getContentType(fileName));
            //指定该Object被下载时的名称（指示MINME用户代理如何显示附加的文件，打开或下载，及文件名称）
            metadata.setContentDisposition("filename/filesize=" + fileName + "/" + fileSize + "Byte.");
            //上传文件   (上传文件流的形式)
            PutObjectResult putResult = ossClient.putObject(bucketName, folder + fileName, is, metadata);
            //解析结果
            resultStr = putResult.getETag();
        } catch (Exception e) {
            e.printStackTrace();
            logger.error("上传阿里云OSS服务器异常." + e.getMessage(), e);
        }
        return resultStr;
    }
    /**
     * 流式下载文件
     * @param ossClient
     * @param
     * @param folder
     */
    public InputStream downloadFile(OSSClient ossClient,String folder,String bucketName) {
        InputStream is=null;
        try {
            // ossObject包含文件所在的存储空间名称、文件名称、文件元信息以及一个输入流。
            OSSObject ossObject = ossClient.getObject(bucketName, folder);
            is = ossObject.getObjectContent();
            return is;
        }catch (OSSException oe) {
            return is;
        }catch(Exception e) {
            return is;
        }catch (Throwable e) {
            e.printStackTrace();
            return is;
        }
    }
    /**
     * 通过文件名判断并获取OSS服务文件上传时文件的contentType
     * @param fileName 文件名
     * @return 文件的contentType
     */
    public static String getContentType(String fileName){
        //文件的后缀名
        String fileExtension = fileName.substring(fileName.lastIndexOf(".")).toLowerCase();
        switch(fileExtension) {
            case ".bmp":
                return "image/bmp";
            case ".gif":
                return "image/gif";
            case ".jpeg":
            case ".jpg":
            case ".png":
                return "image/jpeg";
            case ".html" :
                return "text/html";
            case ".txt":
                return "text/plain";
            case ".vsd":
                return "application/vnd.visio";
            case ".ppt":
            case ".pptx":
                return "application/vnd.ms-powerpoint";
            case ".doc":
            case ".docx":
                return "application/msword";
            case ".xml":
                return "text/xml";
            case ".mp4":
                return "video/mp4";
            case ".awf":
                return "application/vnd.adobe.workflow";
            case ".wav":
                return "audio/wav";
            case ".zip":
                return "application/zip";
            case ".pdf":
                return "application/pdf";
            case ".ogg":
                return "application/ogg";
            case ".js":
                return "application/javascript";
            default:
                return "multipart/form-data";
        }
    }

    /**
     * 获得url链接
     *
     * @param key
     * @return
     */
    public static String getUrl(OSSClient ossClient, String key) {
        // 设置URL过期时间为10年  3600l* 1000*24*365*10
        Date expiration = new Date(System.currentTimeMillis() + 3600L * 1000 * 24 * 365 * 10);
        // 生成URL
        URL url = ossClient.generatePresignedUrl(BACKET_NAME, key, expiration);
        if (url != null) {
            return url.toString();
        }
        return null;
    }


}

 3.加一个配置文件读取工具

   

public class SystemUtil {
    private SystemUtil() {
    }

    private static final Properties properties = new Properties();

    static {
        try {
            properties.load(Thread.currentThread().getContextClassLoader().getResourceAsStream("system.properties"));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private static String getProperty(String keyName) {
        return properties.getProperty(keyName, "").trim();
    }

    private static String getUploadPath(String keyName){
        String os = System.getProperty("os.name").toLowerCase();
        if (os.contains("windows")){
            keyName+="_windows";
        }
        return properties.getProperty(keyName, "").trim();
    }


   /* public static final String UPLOAD_DOMIN = getProperty("domin");

    public static final String UPLOAD_BASE = getUploadPath("upload_base");*/
   public static final String ENDPOINT = getProperty("ENDPOINT");
    public static final String ACCESS_KEY_ID = getProperty("ACCESS_KEY_ID");
    public static final String ACCESS_KEY_SECRET = getProperty("ACCESS_KEY_SECRET");
    public static final String BACKET_NAME = getProperty("BACKET_NAME");
    public static final String FOLDER = getProperty("FOLDER");
}

4.在resourses下新建一个system.properties文件，填入刚才获取的四个。

 

ENDPOINT=
ACCESS_KEY_ID=
ACCESS_KEY_SECRET=
BACKET_NAME=
FOLDER=public/

4.测试

public static void main(String[] args) {
    OSSClient ossClient = AliYunOSSClientUtil.getOSSClient();
  //将文件上传到阿里云
    File file = new File("D:\\2.jpg");
    AliYunOSSClientUtil.uploadObject2OSS(ossClient,file,SystemUtil.BACKET_NAME,SystemUtil.FOLDER);

      //返回下载URL
    String key = SystemUtil.FOLDER+"2.jpg";
    String url = AliYunOSSClientUtil.getUrl(ossClient, key);
    System.out.println(url);
}