commons-net FTPClient.retrieveFileStream() returns wrong result

Question

I have a Problem with commons-net FTPClient. If I download a file from my ftp server wirth retrieveFileStream() it works, but I get the result '150 Opening BINARY mode data connection for ...'. If I call noop() I get '226 Transfer complete' as result. For every following operation I get the result of the prvious operation.

I found out, that FTPClient reads results until end of line, if there are two result lines (as after retrieveFileStream()), I get the second one after the next command. I did a workaround by overriding FTPClient.retrieveFileStream() like this:

public static void main(String[] args){
    try {
        MyFTPClient ftpClient = new MyFTPClient();
        try {
            ftpClient.connect(ftphost, 21);
            if(!ftpClient.login( ftpuser, ftppassword )){
                throw new RuntimeException(ftpClient.getReplyString());
            }
            if(!ftpClient.changeWorkingDirectory("in")){
                throw new RuntimeException(ftpClient.getReplyString());
            }
            FTPFile[] files = ftpClient.listFiles();
            for(FTPFile file: files){
                if(file.getName().startsWith(FILENAME) && (file.getType() == FTPFile.FILE_TYPE)){
                    InputStream in = ftpClient.retrieveFileStream(file.getName());
                    CsvFile csvFile = new CsvFile(in, "ISO-8859-1", ';', "yyyyMMdd", "#.00", Locale.US, false);
                    in.close();
                    in = null;
                    System.out.println(ftpClient.getReplyString());
                    System.out.println(ftpClient.readLine());
                    System.out.println(ftpClient.rnfr(file.getName()));
                    System.out.println(ftpClient.getReplyString());
                    System.out.println(ftpClient.rnto("x" + file.getName()));
                    System.out.println(ftpClient.getReplyString());

                }
            }
            if(!ftpClient.logout()){
                throw new RuntimeException(ftpClient.getReplyString());
            }
        } finally {
            ftpClient.disconnect();
        }

    } catch (Exception e) {
        e.printStackTrace();
    }

}

private static class MyFTPClient extends FTPClient{
    public String readLine(){
        try {
            __getReplyNoReport();
        } catch (IOException e) {
        }
        return getReplyString();
    }
}

The call of the method readLine() gets me the additional Line of result.

But is this a bug of FTPClient or is it a problem of my ftp-server? The Problem of that workaround is, that the method blocks, if there is only one line of response.

Thanx for your help

Stephan

Answer 1

Sometimes it helps, reading the manual. A call of completePendingCommand() works