hadoop文件系统的管理----》可以做网盘的呦

来源：互联网发布：aero开启软件编辑：程序博客网时间：2024/05/05 02:39

今天给大家介绍一下通过hadoop的hdfs和Struts搭建一个网盘的基本框框

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hdfs的基本操作

（1）获得给定路径下的文件列表：

throws FileNotFoundException, IOException {String dst = "hdfs://localhost:9000/" + filename;Configuration conf = new Configuration();FileSystem fs = FileSystem.get(URI.create(dst), conf);FileStatus fileList[] = fs.listStatus(new Path(dst));int size = fileList.length;for (int i = 0; i < fileList.length; i++) {if (fileList[i].getLen() == 0) {//可以通过判断文件的大小来确定是否是文件还是文件夹} else {}}fs.close();return value;

（2）上传文件到hdfs上

     String localSrc = "/home/red-zhu/chen.txt";String dst = "hdfs://localhost:9000/user/" + name;System.out.println(dst);         Configuration conf = new Configuration();FileSystem fs = FileSystem.get(URI.create(dst), conf);OutputStream out = fs.create(new Path(dst), new Progressable() {            public void progress() {System.out.print(".");}});IOUtils.copyBytes(in, out, 4096, true);

（3）下载文件到本地

String dst = "hdfs://localhost:9000/" + path;Configuration conf = new Configuration();FileSystem fs = FileSystem.get(URI.create(dst), conf);FSDataInputStream hdfsInStream = fs.open(new Path(dst));return hdfsInStream;

（4）删除给定路径的文件

String d = "localhost:9000"+path;Configuration conf = new Configuration();FileSystem fs = FileSystem.get(URI.create(dfspath), conf);fs.deleteOnExit(new Path(dst));fs.close();

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struts部分

（2-1）上传实现代码

   private List<File> image;    private List<String> imageContentType;    private List<String> imageFileName;    @Override    public String execute() throws Exception {        String dst = "hdfs://localhost:9000/user/qq1.txt";        String path = ServletActionContext.getServletContext().getRealPath(                "/images");        System.out.println(path);        System.out.println("保存路径为" + path);        if (image.size() > 0) {            /************************/            BufferedInputStream bis = null;            /***********************/            for (int i = 0; i < image.size(); i++) {                System.out.println("datas的个数" + image.size());                String filename = imageFileName.get(i);                FileInputStream fis = new FileInputStream(image.get(i));                bis = new BufferedInputStream(fis);                // FileUtils.copyFile(image.get(i), saveFile);                hdfsUtil.uploadToHdfs(bis, filename);            }        }        // for (int i = 0; i < image.size(); i++)        // {        // File data=image.get(i);        // String fileName=imageFileName.get(i);        // fileName=path+"\\"+fileName;        // data.renameTo(new File(fileName));        // }        return SUCCESS;    }    public List<File> getImage() {        return image;    }    public void setImage(List<File> image) {        this.image = image;    }    public List<String> getImageContentType() {        return imageContentType;    }    public void setImageContentType(List<String> imageContentType) {        this.imageContentType = imageContentType;    }    public List<String> getImageFileName() {        return imageFileName;    }    public void setImageFileName(List<String> imageFileName) {        this.imageFileName = imageFileName;    }

（2-2）下载模块代码

private String fileName;private String flag;public String getFlag() {return flag;}public void setFlag(String flag) {this.flag = flag;}public String getFileName() {return fileName;}public void setFileName(String fileName) {this.fileName = fileName;}public InputStream getInputStream() throws FileNotFoundException,IOException {return hdfsUtil.readFromHdfs((String) (ActionContext.getContext().getSession().get("path"))+flag);}public String execute() {return "success";}

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