public static String uploadFile2OSS(InputStream instream, String fileName) throws IOException {String imageName = null;OSSClient ossClient = null;try {ClientConfiguration conf = new ClientConfiguration();// 请求超时时间设置conf.setConnectionTimeout(5000);// 请求失败重试次数conf.setMaxErrorRetry(3);// 创建上传Object的Metadata，该类为阿里云文件上传内部类，可在里面配置一些基本信息，具体参见源码ObjectMetadata objectMetadata = new ObjectMetadata();objectMetadata.setCacheControl("no-cache");objectMetadata.setHeader("Pragma", "no-cache");objectMetadata.setContentType(getcontentType(fileName.substring(fileName.lastIndexOf("."))));objectMetadata.setContentDisposition("inline;filename=" + fileName);// 上传文件ossClient = new OSSClient(ENDPOINT, ACCESS_KEY_ID, ACCESS_KEY_SECRET);//ENDPOINT：服务器地址，KEY_ID和KEY_SECERT为阿里云颁发的Access Id/Access Key，用于连接服务器PutObjectResult putResult = ossClient.putObject(BUCKET_NAME, fileName, instream, objectMetadata);//BUCKET_NAME为文件上传路径，instream为文件流，String ret = putResult.getETag();if (!"".equals(ret)) {imageName = fileName;}} finally {if (ossClient != null) {ossClient.shutdown();}try {if (instream != null) {instream.close();}} catch (IOException e) {e.printStackTrace();return null;}}return imageName;}
ClientConfiguration客户端配置选项，例如代理设置，用户代理字符串，最大重试次数等。
OSSClient：阿里云文件上传类，
