java - 使用 FTPS 递归复制子目录失败(可能是握手问题？)

Question

我正在尝试使用 FTPS 将给定目录下的所有子目录和文件从 FTP 服务器复制到本地计算机。我编写的程序在轰炸之前获取了一些子目录和文件。每次程序轰炸并不总是在同一个地方。我收到的代码和错误如下。关于如何让它发挥作用有什么想法吗？

import org.apache.commons.net.PrintCommandListener;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPConnectionClosedException;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.commons.net.ftp.FTPReply;
import org.apache.commons.net.ftp.FTPSClient;

public class SaigFileBuilder {

    private String server = "host";
    private String username = "user";
    private String password = "pass";
    private String remoteParentDir = "/prd/fa/out/FA003100/SAIG/";
    private String filesep = System.getProperty("file.separator");
    private String local = "c:" + filesep + "temp" + filesep + "saig_files";
    private List<String> fileList = null;

    private boolean error = false;
    private String protocol = "TLS";  // SSL/TLS
    private FTPSClient ftps = null;



    public static void main(String[] args) {

        SaigFileBuilder fb = new SaigFileBuilder();

        try {
            fb.getClientConnection();            
            fb.getFiles(false);
            fb.logout();

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

        System.exit(fb.error ? 1 : 0);
    }



    private void getClientConnection() throws NoSuchAlgorithmException {

        this.ftps = new FTPSClient(this.protocol);
        this.ftps.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out)));

        this.ftps = getConnection(server);
        this.ftps = getLogin(username, password);
    }

    private FTPSClient getConnection(String server) {

        try
        {
            int reply;

            // Connect to the FTP server...
            this.ftps.connect(server);
            System.out.println("Connected to " + server + ".");

            // Get connect reply code...
            reply = this.ftps.getReplyCode();
            System.out.println("String reply: " + this.ftps.getReplyString());

            // Verify successful connection reply code was returned...
            if (!FTPReply.isPositiveCompletion(reply))
            {
                error = true;
                System.err.println("FTP server refused connection.");
                return null;
            }

            // FileZilla client issues following, so I will too..
            this.ftps.sendCommand("OPTS UTF8 ON");
            this.ftps.execPBSZ(0);
            this.ftps.execPROT("P");
            this.ftps.enterLocalPassiveMode();
        }
        catch (IOException e)
        {
            System.err.println("Could not connect to server.");
            e.printStackTrace();
        }
        return this.ftps;    
    }


    private FTPSClient getLogin(String username, String password) {

        try
        {
            this.ftps.setBufferSize(1000);

            if (!this.ftps.login(username, password))
            {
                System.out.println("Login failed");
                this.ftps.logout();
                return null;
            }

            System.out.println("Remote system is " + this.ftps.getSystemType());

        }
        catch (FTPConnectionClosedException e)
        {
            error = true;
            System.err.println("Server closed connection.");
            e.printStackTrace();
        }
        catch (IOException e)
        {
            error = true;
            e.printStackTrace();
        }

        return this.ftps;
    }



    private void getFiles(boolean binaryTransfer) {
        try
        {
            if (binaryTransfer) { 
                this.ftps.setFileType(FTP.BINARY_FILE_TYPE);
            }

            OutputStream output = null;

            this.ftps.changeWorkingDirectory(this.remoteParentDir);
            System.out.println("pwd: " + this.ftps.printWorkingDirectory());

            this.fileList = new ArrayList<String>();
            scanDirTree(this.remoteParentDir);

            System.out.println("Finished scanning...");
            for (String file : this.fileList) {
            System.out.println(file);
            }

            String dirHold = " ";
            String winDir = " ";
            String winFile = " ";

            for (String ftpFilePath : this.fileList) {
                // Going to copy the remote dirs and files to local, so change the paths to 
                // use local Windows file separator instead of remote Unix... 
                winDir = ftpFilePath.substring(0, ftpFilePath.lastIndexOf("/") + 1).replace("/", filesep);
                winFile = ftpFilePath.substring(ftpFilePath.lastIndexOf("/") + 1, ftpFilePath.length());
                System.out.println("winDir.: " + winDir);
                System.out.println("winFile: " + winFile);

                // If new dir found in list, then create it locally...
                if (dirHold.equals(winDir) == false) {
                    System.out.println("mkdir: " + local + winDir);
                    new File(local + winDir).mkdirs();
                    dirHold = winDir;
                }

                // And write the file locally...
                System.out.println("Attempting to write: " + this.local + winDir + winFile);
                output = new FileOutputStream(local + winDir + winFile);
                this.ftps.retrieveFile(ftpFilePath, output);

                output.close();
                output = null;
            }

        }
        catch (FTPConnectionClosedException e)
        {
            error = true;
            System.err.println("Server closed connection.");
            e.printStackTrace();
        }
        catch (IOException e)
        {
            error = true;
            e.printStackTrace();
        }
    }


    private void scanDirTree(String directory) throws IOException {
        // Create and return a list of all dirs and files on remote 
        // server below the parent dir that was passed to this method...
        FTPFile[] files = this.ftps.listFiles(directory);

        if (files.length == 0) {
            System.out.println("no files in " + directory);
        }

        for (FTPFile file : files) {
            String name = file.getName();


            if (!".".equals(name) && !"..".equals(name)) {
                if (file.isDirectory()) {
                    // Recursive call, go deeper...
                    scanDirTree(directory + name + "/");
                } else {
                    fileList.add(directory + file.getName());
                    System.out.println("Added: " + directory + file.getName());
                }
            }
        }
    }



    private void logout() {

        if (this.ftps.isConnected()) {
            try {
                System.out.println("Logging out...");
                this.ftps.logout();
                System.out.println("Disconnecting...");
                this.ftps.disconnect();
            }
            catch (IOException e) {
                error = true;

            }
        }
    }
}

这是错误:

220 (vsFTPd 2.0.5)
AUTH TLS
234 Proceed with negotiation.
Connected to xxx.xxx.xxx
String reply: 234 Proceed with negotiation.

OPTS UTF8 ON
200 Always in UTF8 mode.
PBSZ 0
200 PBSZ set to 0.
PROT P
200 PROT now Private.
USER xxx
331 Please specify the password.
PASS xxxx
230 Login successful.
SYST
215 UNIX Type: L8
Remote system is UNIX Type: L8
CWD /prd/fa/out/FA003100/SAIG/
250 Directory successfully changed.
PWD
257 "/prd/fa/out/FA003100/SAIG"
pwd: /prd/fa/out/FA003100/SAIG
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,29)
LIST /prd/fa/out/FA003100/SAIG/
150 Here comes the directory listing.
226 Directory send OK.
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,46)
LIST /prd/fa/out/FA003100/SAIG/2012/
150 Here comes the directory listing.
226 Directory send OK.
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,150)
LIST /prd/fa/out/FA003100/SAIG/2012/DirectLoan/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-G.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GCHG.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GDISB.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-U.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UCHG.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UDISB.xml
Added: /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,232)
LIST /prd/fa/out/FA003100/SAIG/2012/Isir/
150 Here comes the directory listing.
226 Directory send OK.
no files in /prd/fa/out/FA003100/SAIG/2012/Isir/
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,254)
LIST /prd/fa/out/FA003100/SAIG/2012/Pell/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN.xml
Added: /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN_DISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,5)
LIST /prd/fa/out/FA003100/SAIG/2012/Teach/
150 Here comes the directory listing.
226 Directory send OK.
no files in /prd/fa/out/FA003100/SAIG/2012/Teach/
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,66)
LIST /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.01
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.02
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.03
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.04
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.05
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.06
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.07
Added: /prd/fa/out/FA003100/SAIG/2012/TrnsMonitorTRNINFIN.01
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,3)
LIST /prd/fa/out/FA003100/SAIG/2013/
150 Here comes the directory listing.
226 Directory send OK.
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,230)
LIST /prd/fa/out/FA003100/SAIG/2013/CommRec/
150 Here comes the directory listing.
226 Directory send OK.
no files in /prd/fa/out/FA003100/SAIG/2013/CommRec/
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,135)
LIST /prd/fa/out/FA003100/SAIG/2013/DLReconciliation/
150 Here comes the directory listing.
226 Directory send OK.
no files in /prd/fa/out/FA003100/SAIG/2013/DLReconciliation/
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,124)
LIST /prd/fa/out/FA003100/SAIG/2013/DirectLoan/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-G.xml
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-GCHG.xml
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-GDISB.xml
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-U.xml
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-UCHG.xml
Added: /prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-UDISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,121)
LIST /prd/fa/out/FA003100/SAIG/2013/Isir/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.001
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.002
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.003
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.004
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.005
Added: /prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.006
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,147)
LIST /prd/fa/out/FA003100/SAIG/2013/Pell/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2013/Pell/CRPG13IN.xml
Added: /prd/fa/out/FA003100/SAIG/2013/Pell/CRPG13IN_DISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,63)
LIST /prd/fa/out/FA003100/SAIG/2013/SysGen/
150 Here comes the directory listing.
226 Directory send OK.
no files in /prd/fa/out/FA003100/SAIG/2013/SysGen/
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,118)
LIST /prd/fa/out/FA003100/SAIG/2013/TrnsMonitor/
150 Here comes the directory listing.
226 Directory send OK.
Added: /prd/fa/out/FA003100/SAIG/2013/TrnsMonitor/TRNINFIN.01
Finished scanning...
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-G.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GCHG.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GDISB.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-U.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UCHG.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UDISB.xml
/prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN.xml
/prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN.xml
/prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN_DISB.xml
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.01
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.02
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.03
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.04
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.05
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.06
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.07
/prd/fa/out/FA003100/SAIG/2012/TrnsMonitorTRNINFIN.01
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-G.xml
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-GCHG.xml
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-GDISB.xml
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-U.xml
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-UCHG.xml
/prd/fa/out/FA003100/SAIG/2013/DirectLoan/CRDL13IN-UDISB.xml
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.001
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.002
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.003
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.004
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.005
/prd/fa/out/FA003100/SAIG/2013/Isir/CORR13IN.006
/prd/fa/out/FA003100/SAIG/2013/Pell/CRPG13IN.xml
/prd/fa/out/FA003100/SAIG/2013/Pell/CRPG13IN_DISB.xml
/prd/fa/out/FA003100/SAIG/2013/TrnsMonitor/TRNINFIN.01
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-G.xml
mkdir: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-G.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,16)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-G.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-G.xml (4561 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-GCHG.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-GCHG.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,136)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GCHG.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GCHG.xml (9074 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-GDISB.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-GDISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,239)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GDISB.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GDISB.xml (2047 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-U.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-U.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,137)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-U.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-U.xml (3367 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-UCHG.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-UCHG.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,243)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UCHG.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UCHG.xml (7503 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN-UDISB.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN-UDISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,87)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UDISB.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UDISB.xml (2995 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\DirectLoan\
winFile: CRDL12IN.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\DirectLoan\CRDL12IN.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,196,251)
RETR /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN.xml (145846 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\Pell\
winFile: CRPG12IN.xml
mkdir: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\Pell\
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\Pell\CRPG12IN.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,123)
RETR /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN.xml (2057 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\Pell\
winFile: CRPG12IN_DISB.xml
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\Pell\CRPG12IN_DISB.xml
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,21)
RETR /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN_DISB.xml
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/Pell/CRPG12IN_DISB.xml (9709 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.01
mkdir: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.01
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,119)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.01
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.01 (453 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.02
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.02
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,101)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.02
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.02 (604 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.03
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.03
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,109)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.03
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.03 (453 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.04
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.04
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,18)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.04
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.04 (453 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.05
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.05
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,84)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.05
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.05 (604 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.06
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.06
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,70)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.06
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.06 (453 bytes).
226 File send OK.
winDir.: \prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\
winFile: TRNINFIN.07
Attempting to write: c:\temp\saig_files\prd\fa\out\FA003100\SAIG\2012\TrnsMonitor\TRNINFIN.07
PASV
227 Entering Passive Mode (xx,xx,xxx,x,197,119)
RETR /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.07
150 Opening BINARY mode data connection for /prd/fa/out/FA003100/SAIG/2012/TrnsMonitor/TRNINFIN.07 (3624 bytes).
org.apache.commons.net.io.CopyStreamException: IOException caught while copying.
    at org.apache.commons.net.io.Util.copyStream(Util.java:135)
    at org.apache.commons.net.ftp.FTPClient._retrieveFile(FTPClient.java:1695)
    at org.apache.commons.net.ftp.FTPClient.retrieveFile(FTPClient.java:1669)
    at edu.ohio.saig.SaigFileBuilder.getFiles(SaigFileBuilder.java:196)
    at edu.ohio.saig.SaigFileBuilder.main(SaigFileBuilder.java:63)
Caused by: javax.net.ssl.SSLHandshakeException: Remote host closed connection during handshake
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readDataRecord(Unknown Source)
    at com.sun.net.ssl.internal.ssl.AppInputStream.read(Unknown Source)
    at java.io.BufferedInputStream.read1(Unknown Source)
    at java.io.BufferedInputStream.read(Unknown Source)
    at java.io.FilterInputStream.read(Unknown Source)
    at java.io.PushbackInputStream.read(Unknown Source)
Logging out...
    at org.apache.commons.net.io.FromNetASCIIInputStream.read(FromNetASCIIInputStream.java:161)
    at org.apache.commons.net.io.FromNetASCIIInputStream.read(FromNetASCIIInputStream.java:139)
    at org.apache.commons.net.io.Util.copyStream(Util.java:101)
    ... 4 more
Caused by: java.io.EOFException: SSL peer shut down incorrectly
    at com.sun.net.ssl.internal.ssl.InputRecord.read(Unknown Source)
    ... 15 more
QUIT

注意我可以使用 FileZilla 手动将父目录复制到本地计算机，所有子目录和文件都会自动复制。以下是 FileZilla session 的日志:

Status: Resolving address of xxx.xxx.xxx
Status: Connecting to xx.xx.xxx.x:21...
Status: Connection established, waiting for welcome message...
Response:   220 (vsFTPd 2.0.5)
Command:    AUTH TLS
Response:   234 Proceed with negotiation.
Status: Initializing TLS...
Status: Verifying certificate...
Command:    USER xxxxx
Status: TLS/SSL connection established.
Response:   331 Please specify the password.
Command:    PASS ************
Response:   230 Login successful.
Command:    OPTS UTF8 ON
Response:   200 Always in UTF8 mode.
Command:    PBSZ 0
Response:   200 PBSZ set to 0.
Command:    PROT P
Response:   200 PROT now Private.
Status: Connected
Status: Sending keep-alive command
Command:    TYPE A
Response:   200 Switching to ASCII mode.
Status: Sending keep-alive command
Command:    PWD
Response:   257 "/prd/fa/out/FA003100/SAIG/2013/TrnsMonitor"
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/TrnsMonitorTRNINFIN.01
Command:    CWD /prd/fa/out/FA003100/SAIG/2012
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN.xml
Command:    CWD /prd/fa/out/FA003100/SAIG/2012/DirectLoan
Response:   250 Directory successfully changed.
Command:    PASV
Response:   250 Directory successfully changed.
Command:    PASV
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,141)
Command:    RETR TrnsMonitorTRNINFIN.01
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,118)
Command:    RETR CRDL12IN.xml
Response:   150 Opening BINARY mode data connection for TrnsMonitorTRNINFIN.01 (3775 bytes).
Response:   150 Opening BINARY mode data connection for CRDL12IN.xml (145846 bytes).
Response:   226 File send OK.
Status: File transfer successful, transferred 3,775 bytes in 1 second
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UDISB.xml
Command:    CWD /prd/fa/out/FA003100/SAIG/2012/DirectLoan
Response:   250 Directory successfully changed.
Command:    TYPE A
Response:   200 Switching to ASCII mode.
Command:    PASV
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,53)
Command:    RETR CRDL12IN-UDISB.xml
Response:   150 Opening BINARY mode data connection for CRDL12IN-UDISB.xml (2995 bytes).
Response:   226 File send OK.
Status: File transfer successful, transferred 145,846 bytes in 1 second
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-UCHG.xml
Command:    PASV
Response:   226 File send OK.
Status: File transfer successful, transferred 2,995 bytes in 1 second
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-U.xml
Command:    PASV
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,123)
Command:    RETR CRDL12IN-UCHG.xml
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,51)
Command:    RETR CRDL12IN-U.xml
Response:   150 Opening BINARY mode data connection for CRDL12IN-UCHG.xml (7503 bytes).
Response:   150 Opening BINARY mode data connection for CRDL12IN-U.xml (3367 bytes).
Response:   226 File send OK.
Status: File transfer successful, transferred 3,367 bytes in 1 second
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GDISB.xml
Command:    PASV
Response:   226 File send OK.
Status: File transfer successful, transferred 7,503 bytes in 1 second
Status: Starting download of /prd/fa/out/FA003100/SAIG/2012/DirectLoan/CRDL12IN-GCHG.xml
Command:    PASV
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,25)
Command:    RETR CRDL12IN-GDISB.xml
Response:   227 Entering Passive Mode (xx,xx,xxx,x,197,28)
Command:    RETR CRDL12IN-GCHG.xml
Response:   150 Opening BINARY mode data connection for CRDL12IN-GDISB.xml (2047 bytes).
Response:   150 Opening BINARY mode data connection for CRDL12IN-GCHG.xml (9074 bytes).
Response:   226 File send OK.
.
.
.
Status: Disconnected from server

Answer 1

好的，我已经找到了错误的原因，但不确定如何解决它。多次调用retrieveFile()方法时会导致该错误。在我看来，该方法向 FTP 服务器发出 PASV 命令。服务器使用随机端口号进行响应，以便客户端检索文件。但是，服务器有时会重用端口，当发生这种情况时，发送 RETR 命令时会引发异常。

我不确定是否需要断开连接并重新连接/登录才能继续。我在异常处理中设置了一个小测试来重新连接，但该测试抛出错误 javax.net.ssl.SSLException: 无法识别的 SSL 消息，纯文本连接。

我会继续努力，但欢迎任何评论/帮助。