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 connection 

            String 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/