FTPClient中 retrieveFileStream 的用法

    工作需要使用了org.apache.commons.net.ftp.FTPClient来操作FTP，记录一下心得。

    这个类封装的很完善，使用起来也很简单，只是在使用retrieveFileStream的时候碰到了一点小问题，就是不知道怎么完成传输状态，尝试发送abor指令也不行。在咨询了bianbian和查看了源代码之后看到这一段说明以后解决问题：

/*
* You must close the InputStream when you
* finish reading from it. The InputStream itself will take care of
* closing the parent data connection socket upon being closed. To
* finalize the file transfer you must call
* {@link #completePendingCommand completePendingCommand } and
* check its return value to verify success.
*/

代码如下：

import org.apache.commons.net.ftp.FTPClient;import java.io.IOException;import java.io.InputStream;import java.net.SocketException;public class TestFTP {public static void main(String[] args) {try {FTPClient ftp = new FTPClient();// initialize ftp connectionString remotefile = "test.xml";InputStream is = null;is = ftp.retrieveFileStream(remotefile);if (is != null) {is.close();}if (!ftp.completePendingCommand()) {ftp.logout();ftp.disconnect();}// continue} catch (SocketException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}} 

博文来源：http://blog.sunshow.net/2007/03/ftpclient-retrievefilestream-usage/