Class FTP

java.lang.Object
org.apache.commons.net.SocketClient
org.apache.commons.net.ftp.FTP
Direct Known Subclasses:
FTPClient
public class FTP extends SocketClient
FTP provides the basic the functionality necessary to implement your own FTP client. It extends org.apache.commons.net.SocketClient since extending TelnetClient was causing unwanted behavior (like connections that did not time out properly).

To derive the full benefits of the FTP class requires some knowledge of the FTP protocol defined in RFC 959. However, there is no reason why you should have to use the FTP class. The FTPClient class, derived from FTP, implements all the functionality required of an FTP client. The FTP class is made public to provide access to various FTP constants and to make it easier for adventurous programmers (or those with special needs) to interact with the FTP protocol and implement their own clients. A set of methods with names corresponding to the FTP command names are provided to facilitate this interaction.

You should keep in mind that the FTP server may choose to prematurely close a connection if the client has been idle for longer than a given time period (usually 900 seconds). The FTP class will detect a premature FTP server connection closing when it receives a FTPReply.SERVICE_NOT_AVAILABLE response to a command. When that occurs, the FTP class method encountering that reply will throw an FTPConnectionClosedException. FTPConectionClosedException is a subclass of IOException and therefore need not be caught separately, but if you are going to catch it separately, its catch block must appear before the more general IOException catch block. When you encounter an FTPConnectionClosedException , you must disconnect the connection with disconnect() to properly clean up the system resources used by FTP. Before disconnecting, you may check the last reply code and text with getReplyCode, getReplyString, and getReplyStrings. You may avoid server disconnections while the client is idle by periodically sending NOOP commands to the server.

Rather than list it separately for each method, we mention here that every method communicating with the server and throwing an IOException can also throw a MalformedServerReplyException , which is a subclass of IOException. A MalformedServerReplyException will be thrown when the reply received from the server deviates enough from the protocol specification that it cannot be interpreted in a useful manner despite attempts to be as lenient as possible.

See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected ProtocolCommandSupport
    _commandSupport_
    A ProtocolCommandSupport object used to manage the registering of ProtocolCommandListeners and the firing of ProtocolCommandEvents.
    protected String
    _controlEncoding
    The character encoding to be used by the FTP control connection.
    protected BufferedReader
    _controlInput_
    Wraps SocketClient.
    protected BufferedWriter
    _controlOutput_
    Wraps SocketClient.
    protected boolean
    _newReplyString
    Whether we've processed the last reply lines.
    protected int
    _replyCode
    The last FTP reply code.
    protected ArrayList<String>
    _replyLines
    The lines of text from the last FTP server response.
    protected String
    _replyString
    The text from the last FTP server response.
    static final int
    ASCII_FILE_TYPE
    A constant used to indicate the file(s) being transferred should be treated as ASCII.
    static final int
    BINARY_FILE_TYPE
    A constant used to indicate the file(s) being transferred should be treated as a binary image, i.e., no translations should be performed.
    static final int
    BLOCK_TRANSFER_MODE
    A constant used to indicate a file is to be transferred as a series of blocks.
    static final int
    CARRIAGE_CONTROL_TEXT_FORMAT
    A constant used to indicate a text file contains ASA vertical format control characters.
    static final int
    COMPRESSED_TRANSFER_MODE
    A constant used to indicate a file is to be transferred as FTP compressed data.
    static final String
    DEFAULT_CONTROL_ENCODING
    The default character encoding used for communicating over an FTP control connection.
    static final int
    DEFAULT_DATA_PORT
    The default FTP data port (20).
    static final int
    DEFAULT_PORT
    The default FTP control port (21).
    static final int
    DEFLATE_TRANSFER_MODE
    A constant used to indicate a file is to be transferred as FTP (un)compressing data in the "deflate" compression format.
    static final int
    EBCDIC_FILE_TYPE
    A constant used to indicate the file(s) being transferred should be treated as EBCDIC.
    static final int
    FILE_STRUCTURE
    A constant used to indicate a file is to be treated as a continuous sequence of bytes.
    static final int
    LOCAL_FILE_TYPE
    A constant used to indicate the file(s) being transferred should be treated as a local type.
    static final int
    NON_PRINT_TEXT_FORMAT
    A constant used for text files to indicate a non-print text format.
    static final int
    PAGE_STRUCTURE
    A constant used to indicate a file is to be treated as a set of independent indexed pages.
    static final int
    RECORD_STRUCTURE
    A constant used to indicate a file is to be treated as a sequence of records.
    static final int
    REPLY_CODE_LEN
    Length of the FTP reply code (3 alphanumerics)
    static final int
    STREAM_TRANSFER_MODE
    A constant used to indicate a file is to be transferred as a stream of bytes.
    protected boolean
    strictMultilineParsing
    This is used to signal whether a block of multiline responses beginning with xxx must be terminated by the same numeric code xxx See section 4.2 of RFC 959 for details.
    static final int
    TELNET_TEXT_FORMAT
    A constant used to indicate a text file contains format vertical format control characters.

    Fields inherited from class SocketClient

    _defaultPort_, _hostname_, _input_, _output_, _serverSocketFactory_, _socket_, _socketFactory_, _timeout_, connectTimeout, NETASCII_EOL, remoteInetSocketAddress

  • Constructor Summary

    Constructors
    Constructor
    Description
    FTP()
    The default FTP constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected void
    __getReplyNoReport()
    Gets the reply, but don't pass it to command listeners.
    protected void
    __noop()
    Send a noop and get the reply without reporting to the command listener.
    protected void
    _connectAction_()
    Initiates control connections and gets initial reply.
    protected void
    _connectAction_(Reader socketIsReader)
    Initiates control connections and gets initial reply.
    int
    abor()
    Sends the FTP ABOR command to the server, receive the reply, and return the reply code.
    int
    acct(String account)
    Sends the FTP ACCT command to the server, receive the reply, and return the reply code.
    int
    allo(int bytes)
    Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
    int
    allo(int bytes, int recordSize)
    Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
    int
    allo(long bytes)
    Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
    int
    allo(long bytes, int recordSize)
    Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
    int
    appe(String path)
    Sends the FTP APPE command to the server, receive the reply, and return the reply code.
    int
    cdup()
    Sends the FTP CDUP command to the server, receive the reply, and return the reply code.
    int
    cwd(String directory)
    Sends the FTP CWD command to the server, receive the reply, and return the reply code.
    int
    dele(String path)
    Sends the FTP DELE command to the server, receive the reply, and return the reply code.
    void
    disconnect()
    Closes the control connection to the FTP server and sets to null some internal data so that the memory may be reclaimed by the garbage collector.
    int
    eprt(InetAddress host, int port)
    Sends the FTP EPRT command to the server, receive the reply, and return the reply code.
    int
    epsv()
    Sends the FTP EPSV command to the server, receive the reply, and return the reply code.
    int
    feat()
    Sends the FTP FEAT command to the server, receive the reply, and return the reply code.
    protected ProtocolCommandSupport
    getCommandSupport()
    Gets protocol command support.
    String
    getControlEncoding()
    Gets the character encoding used to communicate over the control connection.
    int
    getReply()
    Gets a reply from the FTP server and returns the integer reply code.
    int
    getReplyCode()
    Gets the integer value of the reply code of the last FTP reply.
    String
    getReplyString()
    Gets the entire text of the last FTP server response exactly as it was received, including all end of line markers in NETASCII format.
    String[]
    getReplyStrings()
    Gets the lines of text from the last FTP server response as an array of strings, one entry per line.
    int
    help()
    Sends the FTP HELP command to the server, receive the reply, and return the reply code.
    int
    help(String command)
    Sends the FTP HELP command to the server, receive the reply, and return the reply code.
    boolean
    isStrictMultilineParsing()
    Tests whether strict multiline parsing is enabled, as per RFC 959, section 4.2.
    boolean
    isStrictReplyParsing()
    Tests whether strict non-multiline parsing is enabled, as per RFC 959, section 4.2.
    int
    list()
    Sends the FTP LIST command to the server, receive the reply, and return the reply code.
    int
    list(String path)
    Sends the FTP LIST command to the server, receive the reply, and return the reply code.
    int
    mdtm(String file)
    Sends the MDTM command for the given file.
    int
    mfmt(String path, String timeval)
    Sends the FTP MFMT command to the server, receive the reply, and return the reply code.
    int
    mkd(String path)
    Sends the FTP MKD command to the server, receive the reply, and return the reply code.
    int
    mlsd()
    Sends the FTP MLSD command to the server, receive the reply, and return the reply code.
    int
    mlsd(String path)
    Sends the FTP MLSD command to the server, receive the reply, and return the reply code.
    int
    mlst()
    Sends the FTP MLST command to the server, receive the reply, and return the reply code.
    int
    mlst(String path)
    Sends the FTP MLST command to the server, receive the reply, and return the reply code.
    int
    mode(int mode)
    Sends the FTP MODE command to the server, receive the reply, and return the reply code.
    int
    nlst()
    Sends the FTP NLST command to the server, receive the reply, and return the reply code.
    int
    nlst(String path)
    Sends the FTP NLST command to the server, receive the reply, and return the reply code.
    int
    noop()
    Sends the FTP NOOP command to the server, receive the reply, and return the reply code.
    int
    opts(String... commandNameOptions)
    Sends the FTP OPTS command to the server, receive the reply, and return the reply code.
    int
    opts(String commandName, String commandOptions)
    Sends the FTP OPTS command to the server, receive the reply, and return the reply code.
    int
    pass(String password)
    Sends the FTP PASS command to the server, receive the reply, and return the reply code.
    int
    pasv()
    Sends the FTP PASV command to the server, receive the reply, and return the reply code.
    int
    port(InetAddress host, int port)
    Sends the FTP PORT command to the server, receive the reply, and return the reply code.
    int
    pwd()
    Sends the FTP PWD command to the server, receive the reply, and return the reply code.
    int
    quit()
    Sends the FTP QUIT command to the server, receive the reply, and return the reply code.
    int
    rein()
    Sends the FTP REIN command to the server, receive the reply, and return the reply code.
    int
    rest(String marker)
    Sends the FTP REST command to the server, receive the reply, and return the reply code.
    int
    retr(String path)
    Sends the FTP RETR command to the server, receive the reply, and return the reply code.
    int
    rmd(String path)
    Sends the FTP RMD command to the server, receive the reply, and return the reply code.
    int
    rnfr(String path)
    Sends the FTP RNFR command to the server, receive the reply, and return the reply code.
    int
    rnto(String path)
    Sends the FTP RNTO command to the server, receive the reply, and return the reply code.
    int
    sendCommand(int command)
    Sends an FTP command with no arguments to the server, waits for a reply and returns the numerical response code.
    int
    sendCommand(int command, String args)
    Deprecated.
    (3.3) Use sendCommand(FTPCmd, String) instead
    int
    sendCommand(String command)
    Sends an FTP command with no arguments to the server, waits for a reply and returns the numerical response code.
    int
    sendCommand(String command, String args)
    Sends an FTP command to the server, waits for a reply and returns the numerical response code.
    int
    sendCommand(FTPCmd command)
    Sends an FTP command to the server, waits for a reply and returns the numerical response code.
    int
    sendCommand(FTPCmd command, String args)
    Sends an FTP command to the server, waits for a reply and returns the numerical response code.
    void
    setControlEncoding(String encoding)
    Sets the character encoding to be used by the FTP control connection.
    void
    setControlEncoding(Charset charset)
    Sets the character encoding to be used by the FTP control connection.
    void
    setStrictMultilineParsing(boolean strictMultilineParsing)
    Sets strict multiline parsing.
    void
    setStrictReplyParsing(boolean strictReplyParsing)
    Sets strict non-multiline parsing.
    int
    site(String parameters)
    Sends the FTP SITE command to the server, receive the reply, and return the reply code.
    int
    size(String parameters)
    Sends the FTP SIZE command to the server, receive the reply, and return the reply code.
    int
    smnt(String dir)
    Sends the FTP SMNT command to the server, receive the reply, and return the reply code.
    int
    stat()
    Sends the FTP STAT command to the server, receive the reply, and return the reply code.
    int
    stat(String path)
    Sends the FTP STAT command to the server, receive the reply, and return the reply code.
    int
    stor(String path)
    Sends the FTP STOR command to the server, receive the reply, and return the reply code.
    int
    stou()
    Sends the FTP STOU command to the server, receive the reply, and return the reply code.
    int
    stou(String path)
    Sends the FTP STOU command to the server, receive the reply, and return the reply code.
    int
    stru(int structure)
    Sends the FTP STRU command to the server, receive the reply, and return the reply code.
    int
    syst()
    Sends the FTP SYST command to the server, receive the reply, and return the reply code.
    int
    type(int fileType)
    Sends the FTP TYPE command to the server, receive the reply, and return the reply code.
    int
    type(int fileType, int formatOrByteSize)
    Sends the FTP TYPE command for text files to the server, receive the reply, and return the reply code.
    int
    user(String user)
    Sends the FTP USER command to the server, receive the reply, and return the reply code.

    Methods inherited from class SocketClient

    addProtocolCommandListener, applySocketAttributes, checkOpenOutputStream, connect, connect, connect, connect, connect, connect, createCommandSupport, fireCommandSent, fireReplyReceived, getCharset, getCharsetName, getConnectTimeout, getDefaultPort, getDefaultTimeout, getHostAddress, getHostAddress, getKeepAlive, getLocalAddress, getLocalPort, getProxy, getReceiveBufferSize, getRemoteAddress, getRemoteInetSocketAddress, getRemotePort, getSendBufferSize, getServerSocketFactory, getSoLinger, getSoTimeout, getTcpNoDelay, isAvailable, isConnected, removeProtocolCommandListener, setCharset, setConnectTimeout, setDefaultPort, setDefaultTimeout, setKeepAlive, setProxy, setReceiveBufferSize, setSendBufferSize, setServerSocketFactory, setSocketFactory, setSoLinger, setSoTimeout, setTcpNoDelay, verifyRemote

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • DEFAULT_DATA_PORT

      public static final int DEFAULT_DATA_PORT
      The default FTP data port (20).
      See Also:

    • DEFAULT_PORT

      public static final int DEFAULT_PORT
      The default FTP control port (21).
      See Also:

    • ASCII_FILE_TYPE

      public static final int ASCII_FILE_TYPE
      A constant used to indicate the file(s) being transferred should be treated as ASCII. This is the default file type. All constants ending in FILE_TYPE are used to indicate file types.
      See Also:

    • EBCDIC_FILE_TYPE

      public static final int EBCDIC_FILE_TYPE
      A constant used to indicate the file(s) being transferred should be treated as EBCDIC. Note however that there are several EBCDIC formats. All constants ending in FILE_TYPE are used to indicate file types.
      See Also:

    • BINARY_FILE_TYPE

      public static final int BINARY_FILE_TYPE
      A constant used to indicate the file(s) being transferred should be treated as a binary image, i.e., no translations should be performed. All constants ending in FILE_TYPE are used to indicate file types.
      See Also:

    • LOCAL_FILE_TYPE

      public static final int LOCAL_FILE_TYPE
      A constant used to indicate the file(s) being transferred should be treated as a local type. All constants ending in FILE_TYPE are used to indicate file types.
      See Also:

    • NON_PRINT_TEXT_FORMAT

      public static final int NON_PRINT_TEXT_FORMAT
      A constant used for text files to indicate a non-print text format. This is the default format. All constants ending in TEXT_FORMAT are used to indicate text formatting for text transfers (both ASCII and EBCDIC).
      See Also:

    • TELNET_TEXT_FORMAT

      public static final int TELNET_TEXT_FORMAT
      A constant used to indicate a text file contains format vertical format control characters. All constants ending in TEXT_FORMAT are used to indicate text formatting for text transfers (both ASCII and EBCDIC).
      See Also:

    • CARRIAGE_CONTROL_TEXT_FORMAT

      public static final int CARRIAGE_CONTROL_TEXT_FORMAT
      A constant used to indicate a text file contains ASA vertical format control characters. All constants ending in TEXT_FORMAT are used to indicate text formatting for text transfers (both ASCII and EBCDIC).
      See Also:

    • FILE_STRUCTURE

      public static final int FILE_STRUCTURE
      A constant used to indicate a file is to be treated as a continuous sequence of bytes. This is the default structure. All constants ending in _STRUCTURE are used to indicate file structure for file transfers.
      See Also:

    • RECORD_STRUCTURE

      public static final int RECORD_STRUCTURE
      A constant used to indicate a file is to be treated as a sequence of records. All constants ending in _STRUCTURE are used to indicate file structure for file transfers.
      See Also:

    • PAGE_STRUCTURE

      public static final int PAGE_STRUCTURE
      A constant used to indicate a file is to be treated as a set of independent indexed pages. All constants ending in _STRUCTURE are used to indicate file structure for file transfers.
      See Also:

    • STREAM_TRANSFER_MODE

      public static final int STREAM_TRANSFER_MODE
      A constant used to indicate a file is to be transferred as a stream of bytes. This is the default transfer mode. All constants ending in TRANSFER_MODE are used to indicate file transfer modes.
      See Also:

    • BLOCK_TRANSFER_MODE

      public static final int BLOCK_TRANSFER_MODE
      A constant used to indicate a file is to be transferred as a series of blocks. All constants ending in TRANSFER_MODE are used to indicate file transfer modes.
      See Also:

    • COMPRESSED_TRANSFER_MODE

      public static final int COMPRESSED_TRANSFER_MODE
      A constant used to indicate a file is to be transferred as FTP compressed data. All constants ending in TRANSFER_MODE are used to indicate file transfer modes. Currently unused.
      See Also:

    • DEFLATE_TRANSFER_MODE

      public static final int DEFLATE_TRANSFER_MODE
      A constant used to indicate a file is to be transferred as FTP (un)compressing data in the "deflate" compression format. All constants ending in TRANSFER_MODE are used to indicate file transfer modes. See the Internet Draft Deflate transmission mode for FTP
      See Also:

    • DEFAULT_CONTROL_ENCODING

      public static final String DEFAULT_CONTROL_ENCODING
      The default character encoding used for communicating over an FTP control connection. The default encoding is an ASCII-compatible encoding. Some FTP servers expect other encodings. You can change the encoding used by an FTP instance with setControlEncoding.

    • REPLY_CODE_LEN

      public static final int REPLY_CODE_LEN
      Length of the FTP reply code (3 alphanumerics)
      See Also:

    • _replyCode

      protected int _replyCode
      The last FTP reply code.

    • _replyLines

      protected ArrayList<String> _replyLines
      The lines of text from the last FTP server response.

    • _newReplyString

      protected boolean _newReplyString
      Whether we've processed the last reply lines.

    • _replyString

      protected String _replyString
      The text from the last FTP server response.

    • _controlEncoding

      protected String _controlEncoding
      The character encoding to be used by the FTP control connection.

    • _commandSupport_

      protected ProtocolCommandSupport _commandSupport_
      A ProtocolCommandSupport object used to manage the registering of ProtocolCommandListeners and the firing of ProtocolCommandEvents.

    • strictMultilineParsing

      protected boolean strictMultilineParsing
      This is used to signal whether a block of multiline responses beginning with xxx must be terminated by the same numeric code xxx See section 4.2 of RFC 959 for details.

    • _controlInput_

      protected BufferedReader _controlInput_
      Wraps SocketClient._input_ to facilitate the reading of text from the FTP control connection. Do not access the control connection via SocketClient._input_. This member starts with a null value, is initialized in _connectAction_(), and set to null in disconnect().

    • _controlOutput_

      protected BufferedWriter _controlOutput_
      Wraps SocketClient._output_ to facilitate the writing of text to the FTP control connection. Do not access the control connection via SocketClient._output_. This member starts with a null value, is initialized in _connectAction_(), and set to null in disconnect().

  • Constructor Details

    • FTP

      public FTP()
      The default FTP constructor. Sets the default port to DEFAULT_PORT and initializes internal data structures for saving FTP reply information.

  • Method Details

    • __getReplyNoReport

      protected void __getReplyNoReport() throws IOException
      Gets the reply, but don't pass it to command listeners. Used for keep-alive processing only.
      Throws:
      IOException - on error
      Since:
      3.0

    • __noop

      protected void __noop() throws IOException
      Send a noop and get the reply without reporting to the command listener. Intended for use with keep-alive.
      Throws:
      IOException - on error
      Since:
      3.0

    • _connectAction_

      protected void _connectAction_() throws IOException
      Initiates control connections and gets initial reply. Initializes _controlInput_ and _controlOutput_.
      Overrides:
      _connectAction_ in class SocketClient
      Throws:
      IOException - (SocketException) if a problem occurs with the socket

    • _connectAction_

      protected void _connectAction_(Reader socketIsReader) throws IOException
      Initiates control connections and gets initial reply. Initializes _controlInput_ and _controlOutput_.
      Parameters:
      socketIsReader - the reader to reuse (if non-null)
      Throws:
      IOException - on error
      Since:
      3.4

    • abor

      public int abor() throws IOException
      Sends the FTP ABOR command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • acct

      public int acct(String account) throws IOException
      Sends the FTP ACCT command to the server, receive the reply, and return the reply code.
      Parameters:
      account - The account name to access.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • allo

      public int allo(int bytes) throws IOException
      Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
      Parameters:
      bytes - The number of bytes to allocate.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • allo

      public int allo(int bytes, int recordSize) throws IOException
      Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
      Parameters:
      bytes - The number of bytes to allocate.
      recordSize - The size of a record.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • allo

      public int allo(long bytes) throws IOException
      Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
      Parameters:
      bytes - The number of bytes to allocate.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • allo

      public int allo(long bytes, int recordSize) throws IOException
      Sends the FTP ALLO command to the server, receive the reply, and return the reply code.
      Parameters:
      bytes - The number of bytes to allocate.
      recordSize - The size of a record.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • appe

      public int appe(String path) throws IOException
      Sends the FTP APPE command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The path to use for the file when stored at the remote end of the transfer.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • cdup

      public int cdup() throws IOException
      Sends the FTP CDUP command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • cwd

      public int cwd(String directory) throws IOException
      Sends the FTP CWD command to the server, receive the reply, and return the reply code.
      Parameters:
      directory - The new working directory.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • dele

      public int dele(String path) throws IOException
      Sends the FTP DELE command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path to delete.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • disconnect

      public void disconnect() throws IOException
      Closes the control connection to the FTP server and sets to null some internal data so that the memory may be reclaimed by the garbage collector. The reply text and code information from the last command is voided so that the memory it used may be reclaimed. Also sets _controlInput_ and _controlOutput_ to null.
      Overrides:
      disconnect in class SocketClient
      Throws:
      IOException - If an error occurs while disconnecting.

    • eprt

      public int eprt(InetAddress host, int port) throws IOException
      Sends the FTP EPRT command to the server, receive the reply, and return the reply code.

      Examples:

      • EPRT |1|132.235.1.2|6275|
      • EPRT |2|1080::8:800:200C:417A|5282|
      Parameters:
      host - The host owning the port.
      port - The new port.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      2.2
      See Also:
      • "https://datatracker.ietf.org/doc/html/rfc2428"

    • epsv

      public int epsv() throws IOException
      Sends the FTP EPSV command to the server, receive the reply, and return the reply code. Remember, it's up to you to interpret the reply string containing the host/port information.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      2.2

    • feat

      public int feat() throws IOException
      Sends the FTP FEAT command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received by the server
      Throws:
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      2.2

    • getCommandSupport

      protected ProtocolCommandSupport getCommandSupport()
      Gets protocol command support.
      Overrides:
      getCommandSupport in class SocketClient
      Returns:
      the CommandSupport instance, may be null.

    • getControlEncoding

      public String getControlEncoding()
      Gets the character encoding used to communicate over the control connection.
      Returns:
      The character encoding used to communicate over the control connection.

    • getReply

      public int getReply() throws IOException
      Gets a reply from the FTP server and returns the integer reply code. After calling this method, the actual reply text can be accessed from either calling getReplyString or getReplyStrings. Only use this method if you are implementing your own FTP client or if you need to fetch a secondary response from the FTP server.
      Returns:
      The integer value of the reply code of the fetched FTP reply.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while receiving the server reply.

    • getReplyCode

      public int getReplyCode()
      Gets the integer value of the reply code of the last FTP reply. You will usually only use this method after you connect to the FTP server to check that the connection was successful since connect is of type void.
      Returns:
      The integer value of the reply code of the last FTP reply.

    • getReplyString

      public String getReplyString()
      Gets the entire text of the last FTP server response exactly as it was received, including all end of line markers in NETASCII format.
      Returns:
      The entire text from the last FTP response as a String.

    • getReplyStrings

      public String[] getReplyStrings()
      Gets the lines of text from the last FTP server response as an array of strings, one entry per line. The end of line markers of each are stripped from each line.
      Returns:
      The lines of text from the last FTP response as an array.

    • help

      public int help() throws IOException
      Sends the FTP HELP command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • help

      public int help(String command) throws IOException
      Sends the FTP HELP command to the server, receive the reply, and return the reply code.
      Parameters:
      command - The command name on which to request help.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • isStrictMultilineParsing

      public boolean isStrictMultilineParsing()
      Tests whether strict multiline parsing is enabled, as per RFC 959, section 4.2.
      Returns:
      True if strict, false if lenient
      Since:
      2.0

    • isStrictReplyParsing

      public boolean isStrictReplyParsing()
      Tests whether strict non-multiline parsing is enabled, as per RFC 959, section 4.2.

      The default is true, which requires the 3-digit code be followed by space and some text. If false, only the 3-digit code is required (as was the case for versions up to 3.5).

      Returns:
      True if strict (default), false if additional checks are not made
      Since:
      3.6

    • list

      public int list() throws IOException
      Sends the FTP LIST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • list

      public int list(String path) throws IOException
      Sends the FTP LIST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The path to list, may be null in which case the command is sent with no parameters
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • mdtm

      public int mdtm(String file) throws IOException
      Sends the MDTM command for the given file.
      Parameters:
      file - name of file
      Returns:
      the status
      Throws:
      IOException - on error
      Since:
      2.0

    • mfmt

      public int mfmt(String path, String timeval) throws IOException
      Sends the FTP MFMT command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path for which mtime is to be changed
      timeval - Timestamp in yyyyMMDDhhmmss format
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      2.2
      See Also:

    • mkd

      public int mkd(String path) throws IOException
      Sends the FTP MKD command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path of the new directory to create.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • mlsd

      public int mlsd() throws IOException
      Sends the FTP MLSD command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.0

    • mlsd

      public int mlsd(String path) throws IOException
      Sends the FTP MLSD command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - the path to report on
      Returns:
      The reply code received from the server, may be null in which case the command is sent with no parameters
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.0

    • mlst

      public int mlst() throws IOException
      Sends the FTP MLST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.0

    • mlst

      public int mlst(String path) throws IOException
      Sends the FTP MLST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - the path to report on
      Returns:
      The reply code received from the server, may be null in which case the command is sent with no parameters
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.0

    • mode

      public int mode(int mode) throws IOException
      Sends the FTP MODE command to the server, receive the reply, and return the reply code.
      Parameters:
      mode - The transfer mode to use (one of the TRANSFER_MODE constants).
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • nlst

      public int nlst() throws IOException
      Sends the FTP NLST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • nlst

      public int nlst(String path) throws IOException
      Sends the FTP NLST command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The path to list, may be null in which case the command is sent with no parameters
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • noop

      public int noop() throws IOException
      Sends the FTP NOOP command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • opts

      public int opts(String... commandNameOptions) throws IOException
      Sends the FTP OPTS command to the server, receive the reply, and return the reply code.

      FTP request Syntax: 

      opts             = opts-cmd SP command-name [ SP command-options ] CRLF
opts-cmd         = "opts"
command-name     = <any FTP command which allows option setting>
command-options  = <format specified by individual FTP command>
      Parameters:
      commandNameOptions - The OPTS command name and options.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.12.0

    • opts

      public int opts(String commandName, String commandOptions) throws IOException
      Sends the FTP OPTS command to the server, receive the reply, and return the reply code.

      FTP request Syntax: 

      opts             = opts-cmd SP command-name [ SP command-options ] CRLF
opts-cmd         = "opts"
command-name     = <any FTP command which allows option setting>
command-options  = <format specified by individual FTP command>
      Parameters:
      commandName - The OPTS command name.
      commandOptions - The OPTS command options.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.12.0

    • pass

      public int pass(String password) throws IOException
      Sends the FTP PASS command to the server, receive the reply, and return the reply code.
      Parameters:
      password - The plain text password of the user being logged into.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • pasv

      public int pasv() throws IOException
      Sends the FTP PASV command to the server, receive the reply, and return the reply code. Remember, it's up to you to interpret the reply string containing the host/port information.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • port

      public int port(InetAddress host, int port) throws IOException
      Sends the FTP PORT command to the server, receive the reply, and return the reply code.
      Parameters:
      host - The host owning the port.
      port - The new port.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • pwd

      public int pwd() throws IOException
      Sends the FTP PWD command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • quit

      public int quit() throws IOException
      Sends the FTP QUIT command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • rein

      public int rein() throws IOException
      Sends the FTP REIN command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • rest

      public int rest(String marker) throws IOException
      Sends the FTP REST command to the server, receive the reply, and return the reply code.
      Parameters:
      marker - The marker at which to restart a transfer.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • retr

      public int retr(String path) throws IOException
      Sends the FTP RETR command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The path of the file to retrieve.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • rmd

      public int rmd(String path) throws IOException
      Sends the FTP RMD command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path of the directory to remove.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • rnfr

      public int rnfr(String path) throws IOException
      Sends the FTP RNFR command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path to rename from.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • rnto

      public int rnto(String path) throws IOException
      Sends the FTP RNTO command to the server, receive the reply, and return the reply code.
      Parameters:
      path - The path to rename to
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • sendCommand

      public int sendCommand(FTPCmd command) throws IOException
      Sends an FTP command to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The FTPCmd enum corresponding to the FTP command to send.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.3

    • sendCommand

      public int sendCommand(FTPCmd command, String args) throws IOException
      Sends an FTP command to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The FTPCmd enum corresponding to the FTP command to send.
      args - The arguments to the FTP command. If this parameter is set to null, then the command is sent with no argument.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.3

    • sendCommand

      public int sendCommand(int command) throws IOException
      Sends an FTP command with no arguments to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The FTPCommand constant corresponding to the FTP command to send.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • sendCommand

      @Deprecated public int sendCommand(int command, String args) throws IOException
      Deprecated.
      (3.3) Use sendCommand(FTPCmd, String) instead
      Sends an FTP command to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The FTPCommand constant corresponding to the FTP command to send.
      args - The arguments to the FTP command. If this parameter is set to null, then the command is sent with no argument.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • sendCommand

      public int sendCommand(String command) throws IOException
      Sends an FTP command with no arguments to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The text representation of the FTP command to send.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • sendCommand

      public int sendCommand(String command, String args) throws IOException
      Sends an FTP command to the server, waits for a reply and returns the numerical response code. After invocation, for more detailed information, the actual reply text can be accessed by calling getReplyString or getReplyStrings.
      Parameters:
      command - The text representation of the FTP command to send.
      args - The arguments to the FTP command. If this parameter is set to null, then the command is sent with no argument.
      Returns:
      The integer value of the FTP reply code returned by the server in response to the command.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • setControlEncoding

      public void setControlEncoding(Charset charset)
      Sets the character encoding to be used by the FTP control connection. Some FTP servers require that commands be issued in a non-ASCII encoding like UTF-8 so that file names with multi-byte character representations (e.g, Big 8) can be specified.

      Please note that this has to be set before the connection is established.

      Parameters:
      charset - The new character encoding for the control connection.
      Since:
      3.12.0

    • setControlEncoding

      public void setControlEncoding(String encoding)
      Sets the character encoding to be used by the FTP control connection. Some FTP servers require that commands be issued in a non-ASCII encoding like UTF-8 so that file names with multi-byte character representations (e.g, Big 8) can be specified.

      Please note that this has to be set before the connection is established.

      Parameters:
      encoding - The new character encoding for the control connection.

    • setStrictMultilineParsing

      public void setStrictMultilineParsing(boolean strictMultilineParsing)
      Sets strict multiline parsing.
      Parameters:
      strictMultilineParsing - the setting
      Since:
      2.0

    • setStrictReplyParsing

      public void setStrictReplyParsing(boolean strictReplyParsing)
      Sets strict non-multiline parsing.

      If true, it requires the 3-digit code be followed by space and some text. If false, only the 3-digit code is required (as was the case for versions up to 3.5).

      This should not be required by a well-behaved FTP server

      Parameters:
      strictReplyParsing - the setting
      Since:
      3.6

    • site

      public int site(String parameters) throws IOException
      Sends the FTP SITE command to the server, receive the reply, and return the reply code.
      Parameters:
      parameters - The site parameters to send.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • size

      public int size(String parameters) throws IOException
      Sends the FTP SIZE command to the server, receive the reply, and return the reply code.
      Parameters:
      parameters - The site parameters to send.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.
      Since:
      3.7

    • smnt

      public int smnt(String dir) throws IOException
      Sends the FTP SMNT command to the server, receive the reply, and return the reply code.
      Parameters:
      dir - The directory name.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stat

      public int stat() throws IOException
      Sends the FTP STAT command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stat

      public int stat(String path) throws IOException
      Sends the FTP STAT command to the server, receive the reply, and return the reply code.
      Parameters:
      path - A path to list.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stor

      public int stor(String path) throws IOException
      Sends the FTP STOR command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The path to use for the file when stored at the remote end of the transfer.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stou

      public int stou() throws IOException
      Sends the FTP STOU command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stou

      public int stou(String path) throws IOException
      Sends the FTP STOU command to the server, receive the reply, and return the reply code. Remember, it is up to you to manage the data connection. If you don't need this low level of access, use FTPClient , which will handle all low level details for you.
      Parameters:
      path - The base path to use for the file when stored at the remote end of the transfer. Some FTP servers require this.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • stru

      public int stru(int structure) throws IOException
      Sends the FTP STRU command to the server, receive the reply, and return the reply code.
      Parameters:
      structure - The structure of the file (one of the _STRUCTURE constants).
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • syst

      public int syst() throws IOException
      Sends the FTP SYST command to the server, receive the reply, and return the reply code.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • type

      public int type(int fileType) throws IOException
      Sends the FTP TYPE command to the server, receive the reply, and return the reply code.
      Parameters:
      fileType - The type of the file (one of the FILE_TYPE constants).
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • type

      public int type(int fileType, int formatOrByteSize) throws IOException
      Sends the FTP TYPE command for text files to the server, receive the reply, and return the reply code.
      Parameters:
      fileType - The type of the file (one of the FILE_TYPE constants).
      formatOrByteSize - The format of the file (one of the _FORMAT constants). In the case of LOCAL_FILE_TYPE, the byte size.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.

    • user

      public int user(String user) throws IOException
      Sends the FTP USER command to the server, receive the reply, and return the reply code.
      Parameters:
      user - The user to login under.
      Returns:
      The reply code received from the server.
      Throws:
      FTPConnectionClosedException - If the FTP server prematurely closes the connection as a result of the client being idle or some other reason causing the server to send FTP reply code 421. This exception may be caught either as an IOException or independently as itself.
      IOException - If an I/O error occurs while either sending the command or receiving the server reply.