FTPClient download file failed，the retrieveFile() method replyCode=550

问题

/* I run a FTP server on localhost.when I download files use ftpClient.retrieveFile() method,it's replyCode is 550 . I read the API of commons-net and find the 550 replyCode,the defines is" public static final int FILE_UNAVAILABLE 550".but I cannot find the problem from my codes.
thanks for your help.

    FTPClient ftpClient = new FTPClient();
    FileOutputStream fos = null;

    try {
        ftpClient.connect("192.168.1.102",2121);
        ftpClient.login("myusername", "12345678");
        ftpClient.setControlEncoding("UTF-8");
        ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE);
        String remoteFileName = "ftpserver.zip";//this file in the rootdir
        fos = new FileOutputStream("f:/down.zip");
        ftpClient.setBufferSize(1024);
        ftpClient.enterLocalPassiveMode();
        ftpClient.enterLocalActiveMode();
        ftpClient.retrieveFile(remoteFileName, fos);  
        System.out.println("retrieveFile?"+ftpClient.getReplyCode());
        fos.close();
        ftpClient.logout();
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            ftpClient.disconnect();
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException("关闭FTP异常", e);
        }
    }

回答1:

I found that Apache retrieveFile(...) sometimes did not work with File Sizes exceeding a certain limit. To overcome that I would used retrieveFileStream() instead. Prior to download I have set the Correct FileType and set the Mode to PassiveMode

So the code will look like

    ....
    ftpClientConnection.setFileType(FTP.BINARY_FILE_TYPE);
    ftpClientConnection.enterLocalPassiveMode();
    ftpClientConnection.setAutodetectUTF8(true);

    //Create an InputStream to the File Data and use FileOutputStream to write it
    InputStream inputStream = ftpClientConnection.retrieveFileStream(ftpFile.getName());
    FileOutputStream fileOutputStream = new FileOutputStream(directoryName + "/" + ftpFile.getName());
    //Using org.apache.commons.io.IOUtils
    IOUtils.copy(inputStream, fileOutputStream);
    fileOutputStream.flush();
    IOUtils.closeQuietly(fileOutputStream);
    IOUtils.closeQuietly(inputStream);
    boolean commandOK = ftpClientConnection.completePendingCommand();
    ....

回答2:

FTP Error 550 Requested action not taken. File unavailable, not found, not accessible

So I think the enconding is a bit wierd, I do not set control encoding and use the retrieveFile just sending a normal String in java. Also this line:

ftpClient.retrieveFile(new String(remoteFileName.getBytes("ms932"),"ISO-8859-1"), fos);

does nothing because you are creating a new Java string from another string. Java strings are kept in memory in a different encoding, compatible with all encodings if I am not mistaken.

Also, the path you are using is wrong, see:

String remoteFileName = "//ftpserver.zip";

Ftp will cause error starting a path with /, try this:

"ftpserver.zip"

or if you have a subdir, try this:

"subdir/myfile.zip"

Cheers

回答3:

Recently i came across the same error but it was mainly because the path was incorrect and instead of appending a slash as in /data/csms/trt/file.txt it was getting appended as /data/csms/trtfile.txt ...so the file was not being retrieved from the desired location.

回答4:

setControlEncoding needs to be called before connect, like this

[...]
try {
    ftpClient.setControlEncoding("UTF-8");
    ftpClient.connect("192.168.1.102",2121);
    ftpClient.login("myusername", "12345678");
[...]

回答5:

Looks like the output path isn't correct. Check the shared root directory on your server. If the root is f:\ and your file is in this root directory, then you only need to do this: `fos = new FileOutputStream("down.zip");

If your file is in a sub-directory of the root, for example, f:\sub, then it should be fos = new FileOutputStream("sub\\down.zip");

回答6:

I had the same problem, because i had no space in my SDCARD/PHONE Memory.

来源：https://stackoverflow.com/questions/7558732/ftpclient-download-file-failed-the-retrievefile-method-replycode-550

标签

java

ftp

apache-commons-net