Class FTPControlChannel

java.lang.Object

org.globus.ftp.vanilla.BasicClientControlChannel

org.globus.ftp.vanilla.FTPControlChannel

Direct Known Subclasses:

GridFTPControlChannel

public class FTPControlChannel
extends BasicClientControlChannel

Represents FTP Protocol Interpreter. Encapsulates control channel communication.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CRLF
protected BufferedReader	ftpIn
protected OutputStream	ftpOut
protected boolean	hasBeenOpened
protected String	host
private boolean	ipv6
private Reply	lastReply
private static org.apache.commons.logging.Log	logger
protected int	port
protected InputStream	rawFtpIn
protected Socket	socket
private static final int	WAIT_FOREVER

Constructor Summary

Constructors

Constructor	Description
FTPControlChannel(InputStream in, OutputStream out)	Using this constructor, you can initialize an instance that does not talk directly to the socket.
FTPControlChannel(String host, int port)

Method Summary

Modifier and Type	Method	Description
void	abortTransfer()
private int	checkSocketDone(Flag aborted, int ioDelay, int maxWait)
void	close()	Closes the control channel
Reply	exchange(Command cmd)	Write the command to the control channel, block until reply arrives and return the reply.
Reply	execute(Command cmd)	Write the command to the control channel, block until reply arrives and check if the command completed successfully (reply code 200).
protected BufferedReader	getBufferedReader()
String	getHost()
Reply	getLastReply()	Returns the last reply received from the server.
protected OutputStream	getOutputStream()
int	getPort()
protected boolean	hasBeenOpened()
protected boolean	haveStreams()
boolean	isIPv6()
void	open()	opens the connection and returns after it is ready for communication.
Reply	read()	Block until a reply is available in the control channel.
protected void	readInitialReplies()
protected void	setInputStream(InputStream in)
protected void	setOutputStream(OutputStream out)
void	waitFor(Flag aborted, int ioDelay, int maxWait)	Block until one of the conditions are true: a reply is available in the control channel, timeout (maxWait) expired aborted flag changes to true.
void	write(Command cmd)	Sends the command over the control channel.
protected void	writeln(String msg)
protected void	writeStr(String msg)

Methods inherited from class BasicClientControlChannel

waitFor

Methods inherited from class Object

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

Field Details

logger

private static org.apache.commons.logging.Log logger

CRLF

public static final String CRLF

See Also:

• Constant Field Values

WAIT_FOREVER

private static final int WAIT_FOREVER

See Also:

• Constant Field Values

socket

protected Socket socket

ftpIn

protected BufferedReader ftpIn

rawFtpIn

protected InputStream rawFtpIn

ftpOut

protected OutputStream ftpOut

host

protected String host

port

protected int port

hasBeenOpened

protected boolean hasBeenOpened

ipv6

private boolean ipv6

lastReply

private Reply lastReply

Constructor Details

FTPControlChannel

public FTPControlChannel(String host,
 int port)

FTPControlChannel

public FTPControlChannel(InputStream in,
 OutputStream out)

Using this constructor, you can initialize an instance that does not talk directly to the socket. If you use this constructor using streams that belong to an active connection, there's no need to call open() afterwards.

Method Details

getHost

public String getHost()

getPort

public int getPort()

isIPv6

public boolean isIPv6()

getBufferedReader

protected BufferedReader getBufferedReader()

getOutputStream

protected OutputStream getOutputStream()

setInputStream

protected void setInputStream(InputStream in)

setOutputStream

protected void setOutputStream(OutputStream out)

open

public void open()
          throws IOException,
ServerException

opens the connection and returns after it is ready for communication. Before returning, it intercepts the initial server reply(-ies), and not positive, throws UnexpectedReplyCodeException. After returning, there should be no more queued replies on the line. Here's the sequence for connection establishment (rfc959):

     120
         220
     220
     421

Throws:

IOException - on I/O error

ServerException - on negative or faulty server reply

readInitialReplies

protected void readInitialReplies()
                           throws IOException,
ServerException

Throws:

IOException

ServerException

getLastReply

public Reply getLastReply()

Returns the last reply received from the server.

close

public void close()
           throws IOException

Closes the control channel

Throws:

IOException

checkSocketDone

private int checkSocketDone(Flag aborted,
 int ioDelay,
 int maxWait)
                     throws ServerException,
IOException,
InterruptedException

Throws:

ServerException

IOException

InterruptedException

waitFor

public void waitFor(Flag aborted,
 int ioDelay,
 int maxWait)
             throws ServerException,
IOException,
InterruptedException

Block until one of the conditions are true:

1. a reply is available in the control channel,
2. timeout (maxWait) expired
3. aborted flag changes to true.

If maxWait == WAIT_FOREVER, never timeout and only check conditions (1) and (3).

Specified by:

waitFor in class BasicClientControlChannel

Parameters:

aborted - flag indicating wait aborted.

ioDelay - frequency of polling the control channel and checking the conditions

maxWait - timeout in miliseconds

Throws:

ServerException

IOException

InterruptedException

read

public Reply read()
           throws ServerException,
IOException,
FTPReplyParseException,
EOFException

Block until a reply is available in the control channel.

Specified by:

read in class BasicClientControlChannel

Returns:

the first unread reply from the control channel.

Throws:

IOException - on I/O error

FTPReplyParseException - on malformatted server reply

ServerException

EOFException

abortTransfer

public void abortTransfer()

Specified by:

abortTransfer in class BasicClientControlChannel

write

public void write(Command cmd)
           throws IOException,
IllegalArgumentException

Sends the command over the control channel. Do not wait for reply.

Parameters:

cmd - FTP command

Throws:

IOException - on I/O error

IllegalArgumentException

exchange

public Reply exchange(Command cmd)
               throws ServerException,
IOException,
FTPReplyParseException

Write the command to the control channel, block until reply arrives and return the reply. Before calling this method make sure that no old replies are waiting on the control channel. Otherwise the reply returned may not be the reply to this command.

Parameters:

cmd - FTP command

Returns:

the first reply that waits in the control channel

Throws:

IOException - on I/O error

FTPReplyParseException - on bad reply format

ServerException

execute

public Reply execute(Command cmd)
              throws ServerException,
IOException,
FTPReplyParseException,
UnexpectedReplyCodeException

Write the command to the control channel, block until reply arrives and check if the command completed successfully (reply code 200). If so, return the reply, otherwise throw exception. Before calling this method make sure that no old replies are waiting on the control channel. Otherwise the reply returned may not be the reply to this command.

Parameters:

cmd - FTP command

Returns:

the first reply that waits in the control channel

Throws:

IOException - on I/O error

FTPReplyParseException - on bad reply format

UnexpectedReplyCodeException - if reply is not a positive completion reply (code 200)

ServerException

writeln

protected void writeln(String msg)
                throws IOException

Throws:

IOException

writeStr

protected void writeStr(String msg)
                 throws IOException

Throws:

IOException

hasBeenOpened

protected boolean hasBeenOpened()

haveStreams

protected boolean haveStreams()