Java客户端使用FastDFS上传文件

2019-01-09

前言

在搭建完成fdfs文件服务器之后，我们就可以使用这个文件服务器的功能了，fdfs提供了一个java客户端，接下来看看如何简单在java中使用fdfs上传文件。

准备

首先我们要添加依赖：

    <dependency>
        <groupId>org.csource</groupId>
        <artifactId>fastdfs-client-java</artifactId>
        <version>1.27-SNAPSHOT</version>
    </dependency>

自己定义一个FastDFSFile类，这个类作为要上传的文件的载体

public class FastDFSFile {
    //文件名
    private String name;
    //内容
    private byte[] content;
    //扩展名
    private String ext;
    //md5串
    private String md5;
    //拥有者
    private String author;

    public FastDFSFile(String name, byte[] content, String ext, String height,
                       String width, String author) {
        super();
        this.name = name;
        this.content = content;
        this.ext = ext;
        this.author = author;
    }

    public FastDFSFile(String name, byte[] content, String ext) {
        super();
        this.name = name;
        this.content = content;
        this.ext = ext;

    }
 //省略get set方法
}

接下来需要一个客户端FastDFSClient

public class FastDFSClient {
    private static org.slf4j.Logger logger = LoggerFactory.getLogger(FastDFSClient.class);

    static {
        try {
            //加载配置信息
            String filePath = new ClassPathResource("fdfs_client.conf").getFile().getAbsolutePath();;
            ClientGlobal.init(filePath);
        } catch (Exception e) {
            logger.error("FastDFS Client Init Fail!",e);
        }
    }

    /**
     * 上传文件
     * @param file
     * @return
     */
    public static String[] upload(FastDFSFile file) {
        //打印文件信息
        logger.info("File Name: " + file.getName() + "File Length:" + file.getContent().length);

        NameValuePair[] meta_list = new NameValuePair[1];
        meta_list[0] = new NameValuePair("author", file.getAuthor());

        long startTime = System.currentTimeMillis();
        String[] uploadResults = null;
        StorageClient storageClient=null;
        try {
            storageClient = getTrackerClient();
            uploadResults = storageClient.upload_file(file.getContent(), file.getExt(), meta_list);
        } catch (IOException e) {
            logger.error("IO Exception when uploadind the file:" + file.getName(), e);
        } catch (Exception e) {
            logger.error("Non IO Exception when uploadind the file:" + file.getName(), e);
        }
        logger.info("upload_file time used:" + (System.currentTimeMillis() - startTime) + " ms");

        //上传异常
        if (uploadResults == null && storageClient!=null) {
            logger.error("upload file fail, error code:" + storageClient.getErrorCode());
        }
        String groupName = uploadResults[0];
        String remoteFileName = uploadResults[1];

        logger.info("upload file successfully!!!" + "group_name:" + groupName + ", remoteFileName:" + " " + remoteFileName);
        return uploadResults;
    }


    public static String getTrackerUrl() throws IOException {
        return "http://"+getTrackerServer().getInetSocketAddress().getHostString()+":"+ClientGlobal.getG_tracker_http_port()+"/";
    }

    private static StorageClient getTrackerClient() throws IOException {
        TrackerServer trackerServer = getTrackerServer();
        StorageClient storageClient = new StorageClient(trackerServer, null);
        return  storageClient;
    }

    private static TrackerServer getTrackerServer() throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return  trackerServer;
     }
    }

我们在FastDFSClient中的静态块需要加载一个配置文件fdfs_client.conf。

内容如下：

connect_timeout = 60
network_timeout = 60
charset = UTF-8
http.tracker_http_port = 8008
#关闭token认证
http.anti_steal_token = no
#token认证密钥
http.secret_key = 123456

tracker_server = 192.168.53.86:22122

这些准备好了之后就可以写个controller来测试一下了。

 @PostMapping("/upload")
    public String singleFileUpload(@RequestParam("file") MultipartFile file,//用@RequestParam获取传递过来的文件
                                   RedirectAttributes redirectAttributes) {
        if (file.isEmpty()) {
            redirectAttributes.addFlashAttribute("message", "Please select a file to upload");
            return "redirect:uploadStatus";
        }
        try {
            // 获取文件保存
            String path=saveFile(file);
            redirectAttributes.addFlashAttribute("message",
                    "You successfully uploaded '" + file.getOriginalFilename() + "'");
            redirectAttributes.addFlashAttribute("path",
                    "file path url '" + path + "'");
        } catch (Exception e) {
            logger.error("upload file failed",e);
        }
        return "redirect:/uploadStatus";
    }

    @GetMapping("/uploadStatus")
    public String uploadStatus() {
        return "uploadStatus";
    }

    /**
     * @param multipartFile
     * @return
     * @throws IOException
     */
    public String saveFile(MultipartFile multipartFile) throws IOException {
        String[] fileAbsolutePath={};
        String fileName=multipartFile.getOriginalFilename();
        String ext = fileName.substring(fileName.lastIndexOf(".") + 1);
        byte[] file_buff = null;
        InputStream inputStream=multipartFile.getInputStream();
        if(inputStream!=null){
            int len1 = inputStream.available();
            file_buff = new byte[len1];
            inputStream.read(file_buff);
        }
        inputStream.close();
        //构造一个FastDFSFile对象
        FastDFSFile file = new FastDFSFile(fileName, file_buff, ext);
        try {
            fileAbsolutePath = FastDFSClient.upload(file);  //上传到fastdfs
        } catch (Exception e) {
            logger.error("upload file Exception!",e);
        }
        if (fileAbsolutePath==null) {
            logger.error("upload file failed,please upload again!");
        }
        //上传成功返回文件path
        String path=FastDFSClient.getTrackerUrl()+fileAbsolutePath[0]+ "/"+fileAbsolutePath[1];
        return path;
    }