sk.fiit.jim.agent.server

Class TFTPServer

java.lang.Object

sk.fiit.jim.agent.server.TFTPServer

All Implemented Interfaces:

Runnable

public class TFTPServer
extends Object
implements Runnable

A fully multi-threaded tftp server. Can handle multiple clients at the same time. Implements RFC 1350 and wrapping block numbers for large file support. To launch, just create an instance of the class. An IOException will be thrown if the server fails to start for reasons such as port in use, port denied, etc. To stop, use the shutdown method. To check to see if the server is still running (or if it stopped because of an error), call the isRunning() method. By default, events are not logged to stdout/stderr. This can be changed with the setLog and setLogError methods.

Example usage is below: public static void main(String[] args) throws Exception { if (args.length != 1) { System.out .println("You must provide 1 argument - the base path for the server to serve from."); System.exit(1); } TFTPServer ts = new TFTPServer(new File(args[0]), new File(args[0]), GET_AND_PUT); ts.setSocketTimeout(2000); System.out.println("TFTP Server running. Press enter to stop."); new InputStreamReader(System.in).read(); ts.shutdown(); System.out.println("Server shut down."); System.exit(0); }

Since:

2.0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TFTPServer.ServerMode
private class	TFTPServer.TFTPTransfer

Field Summary

Fields

Modifier and Type	Field and Description
private static int	DEFAULT_TFTP_PORT
private PrintStream	log_
private PrintStream	logError_
private int	maxTimeoutRetries_
private TFTPServer.ServerMode	mode_
private static PrintStream	nullStream
private int	port_
private Exception	serverException
private File	serverReadDirectory_
private org.apache.commons.net.tftp.TFTP	serverTftp_
private Thread	serverThread
private File	serverWriteDirectory_
private boolean	shutdownServer
private int	socketTimeout_
private HashSet<TFTPServer.TFTPTransfer>	transfers_

Constructor Summary

Constructors

Constructor and Description
TFTPServer(File serverReadDirectory, File serverWriteDirectory, int port, TFTPServer.ServerMode mode, PrintStream log, PrintStream errorLog) Start a TFTP Server on the specified port.
TFTPServer(File serverReadDirectory, File serverWriteDirectory, TFTPServer.ServerMode mode) Start a TFTP Server on the default port (69).

Method Summary

Methods

Modifier and Type	Method and Description
protected void	finalize()
int	getMaxTimeoutRetries() Get the current value for maxTimeoutRetries
int	getSocketTimeout() The current socket timeout used during transfers in milliseconds.
boolean	isRunning() check if the server thread is still running.
private void	launch(File serverReadDirectory, File serverWriteDirectory)
void	run()
void	setLog(PrintStream log) Set the stream object to log debug / informational messages.
void	setLogError(PrintStream logError) Set the stream object to log error messsages.
void	setMaxTimeoutRetries(int retries) Set the max number of retries in response to a timeout.
void	setSocketTimeout(int timeout) Set the socket timeout in milliseconds used in transfers.
void	shutdown() Stop the tftp server (and any currently running transfers) and release all opened network resources.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_TFTP_PORT

private static final int DEFAULT_TFTP_PORT

See Also:

Constant Field Values

transfers_

private HashSet<TFTPServer.TFTPTransfer> transfers_

shutdownServer

private volatile boolean shutdownServer

serverTftp_

private org.apache.commons.net.tftp.TFTP serverTftp_

serverReadDirectory_

private File serverReadDirectory_

serverWriteDirectory_

private File serverWriteDirectory_

port_

private int port_

serverException

private Exception serverException

mode_

private TFTPServer.ServerMode mode_

nullStream

private static final PrintStream nullStream

log_

private PrintStream log_

logError_

private PrintStream logError_

maxTimeoutRetries_

private int maxTimeoutRetries_

socketTimeout_

private int socketTimeout_

serverThread

private Thread serverThread

Constructor Detail

TFTPServer

public TFTPServer(File serverReadDirectory,
          File serverWriteDirectory,
          TFTPServer.ServerMode mode)
           throws IOException

Start a TFTP Server on the default port (69). Gets and Puts occur in the specified directories. The server will start in another thread, allowing this constructor to return immediately. If a get or a put comes in with a relative path that tries to get outside of the serverDirectory, then the get or put will be denied. GET_ONLY mode only allows gets, PUT_ONLY mode only allows puts, and GET_AND_PUT allows both. Modes are defined as int constants in this class.

Parameters:

serverReadDirectory - directory for GET requests

serverWriteDirectory - directory for PUT requests

mode - A value as specified above.

Throws:

IOException - if the server directory is invalid or does not exist.

TFTPServer

public TFTPServer(File serverReadDirectory,
          File serverWriteDirectory,
          int port,
          TFTPServer.ServerMode mode,
          PrintStream log,
          PrintStream errorLog)
           throws IOException

Start a TFTP Server on the specified port. Gets and Puts occur in the specified directory. The server will start in another thread, allowing this constructor to return immediately. If a get or a put comes in with a relative path that tries to get outside of the serverDirectory, then the get or put will be denied. GET_ONLY mode only allows gets, PUT_ONLY mode only allows puts, and GET_AND_PUT allows both. Modes are defined as int constants in this class.

Parameters:

serverReadDirectory - directory for GET requests

serverWriteDirectory - directory for PUT requests

mode - A value as specified above.

log - Stream to write log message to. If not provided, uses System.out

errorLog - Stream to write error messages to. If not provided, uses System.err.

Throws:

IOException - if the server directory is invalid or does not exist.

Method Detail

setMaxTimeoutRetries

public void setMaxTimeoutRetries(int retries)

Set the max number of retries in response to a timeout. Default 3. Min 0.

Parameters:

retries -

getMaxTimeoutRetries

public int getMaxTimeoutRetries()

Get the current value for maxTimeoutRetries

setSocketTimeout

public void setSocketTimeout(int timeout)

Set the socket timeout in milliseconds used in transfers. Defaults to the value here: http://commons.apache.org/net/apidocs/org/apache/commons/net/tftp/TFTP.html#DEFAULT_TIMEOUT (5000 at the time I write this) Min value of 10.

getSocketTimeout

public int getSocketTimeout()

The current socket timeout used during transfers in milliseconds.

launch

private void launch(File serverReadDirectory,
          File serverWriteDirectory)
             throws IOException

Throws:

IOException

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

isRunning

public boolean isRunning()
                  throws Exception

check if the server thread is still running.

Returns:

true if running, false if stopped.

Throws:

Exception - throws the exception that stopped the server if the server is stopped from an exception.

run

public void run()

Specified by:

run in interface Runnable

shutdown

public void shutdown()

Stop the tftp server (and any currently running transfers) and release all opened network resources.

setLog

public void setLog(PrintStream log)

Set the stream object to log debug / informational messages. By default, this is a no-op

Parameters:

log -

setLogError

public void setLogError(PrintStream logError)

Set the stream object to log error messsages. By default, this is a no-op

Parameters:

logError -