JAVA使用FTP上传下载文件的问题

为了实现 FTP上传下载,大概试了两个方法

sun.net.ftp.FtpClient

org.apache.commons.net

 

一开始使用sun.net.ftp.FtpClient,结果发现唯一的问题是它不可以创建目录,

随后试了下org.apache.commons.net,创建目录倒是没有问题,不过用FTPClient 的storeFile方法存储文件的时候发现文本文件正常,但是存储word 或者是压缩包等等的文件就会损坏,由于时间紧迫,网上也没有找到有效的解决办法,结果最后还是采用sun.net.ftp.FtpClient方法

sun.net.ftp.FtpClient中的sendserver方法可以发送FTP服务器的命令,从而可以通过它发送XMDK命令来创建目录

值得注意的是使用sendserver发送命令后，还应该要解析发回来的返回信息。并不是一个命令发送完后就可以发送下一个命令。有时候要等待到就绪状态才行。

使用ftpclient.readServerResponse来接收服务器发回来的执行结果

 

 

附代码:

sun.net.ftp.FtpClient:

    // 连接ftp服务器

    private void connectServer(String server, String user, String password, String path) throws IOException {

            ftpClient_sun = new FtpClient();

            ftpClient_sun = new FtpClient();

            ftpClient_sun.openServer(server,22);

            ftpClient_sun.login(user, password);

            // path是FTP服务下主目录的子目录

            if (path.length() != 0)

                ftpClient_sun.cd(path);

            ftpClient_sun.sendServer("XMKD test\r\n");

            ftpClient_sun.readServerResponse();

            ftpClient_sun.cd("test");

            // 用2进制上传

            ftpClient_sun.binary();

            System.out.println("登录成功");

       

    }

    // 上传文件;并返回上传文件的信息

    private String upload(FormFile formFile) throws Exception {

        TelnetOutputStream os = null;

        InputStream is = null;

        try {

            os = ftpClient_sun.put("upftp"+getName()+"." + getExtName(formFile.getFileName()));

            is = formFile.getInputStream();

            byte[] bytes = new byte[1024];

            int c;

            while ((c = is.read(bytes)) != -1) {

                os.write(bytes, 0, c);

            }

        } finally {

            if (is != null) {

                is.close();

            }

            if (os != null) {

                os.close();

            }

        }

        return "上传文件成功!";

    }

   

    /**

     * 下载文件

     *

     * @param fileName

     *            FormFile对象

     * @param HttpServletResponse

     *            HTTP响应

     * @throws IOException

     */

    private void download(String fileName, HttpServletResponse response) throws IOException {

        TelnetInputStream ftpIn = ftpClient_sun.get(fileName);

        response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));

        OutputStream out = null;

        try {

            out = response.getOutputStream();

            IOUtils.copy(ftpIn, out);

        } finally {

            if (ftpIn != null) {

                ftpIn.close();

            }

        }

    }

    /**

     * 展示图片     *

     * @param fileName

     *            FormFile对象

     * @param HttpServletResponse

     *            HTTP响应

     * @throws IOException

     */

    private void show(String fileName, HttpServletResponse response) throws IOException {

        TelnetInputStream ftpIn = ftpClient_sun.get(fileName);

        OutputStream out = null;

        try {

            out = response.getOutputStream();

            IOUtils.copy(ftpIn, out);

        } finally {

            if (ftpIn != null) {

                ftpIn.close();

            }

        }

    }

org.apache.commons.net

    // 连接ftp服务器

    private void connectServer(String server, String user, String password, String path) throws IOException {

        try {

            ftpClient = new FTPClient();

            ftpClient.connect(server);

            ftpClient.login(user, password);

            System.out.println(" login success !!! ");

            if (path.length() != 0) {

              boolean flag = ftpClient.changeWorkingDirectory(path);

              if (flag) {

                System.out.println(" set working directory successful !!! ");

              }else

              {

                  ftpClient.makeDirectory(path);

                  ftpClient.changeWorkingDirectory(path);

              }

            }

          }

          catch (IOException e) {

              System.out.println(" not login !!! ");

              System.out.println(e.getMessage());

          }

    }

    // 上传文件;并返回上传文件的信息

    private String upload(FormFile formFile) throws Exception {

        InputStream fis = formFile.getInputStream();

        // 上传本地文件到服务器上(文件名以'temp_'开头，当上传完毕后，名字改为正式名)

        boolean flag = ftpClient.storeFile("upftp"+getName()+"."+getExtName(formFile.getFileName()), fis);

        if (flag) {

            System.out.println(" upload success !!! ");

        }

        // 关闭文件流

        fis.close();

        return "上传文件成功!";

    }