org.apache.commons.net.tftp
Class TFTP
DatagramSocketClient
org.apache.commons.net.tftp.TFTP
public class TFTP
extends DatagramSocketClient
The TFTP class exposes a set of methods to allow you to deal with the TFTP
protocol directly, in case you want to write your own TFTP client or
server. However, almost every user should only be concerend with
the
open()
,
and
close()
,
methods. Additionally,the a
setDefaultTimeout()
method may be of importance for performance tuning.
Details regarding the TFTP protocol and the format of TFTP packets can
be found in RFC 783. But the point of these classes is to keep you
from having to worry about the internals.
org.apache.commons.net.DatagramSocketClient
, TFTPPacket
, TFTPPacketException
, TFTPClient
static int | ASCII_MODE -
The ascii transfer mode.
|
static int | BINARY_MODE -
The binary transfer mode.
|
static int | DEFAULT_PORT -
The default TFTP port according to RFC 783 is 69.
|
static int | DEFAULT_TIMEOUT -
The default number of milliseconds to wait to receive a datagram
before timing out.
|
static int | IMAGE_MODE -
The image transfer mode.
|
static int | NETASCII_MODE -
The netascii transfer mode.
|
static int | OCTET_MODE -
The octet transfer mode.
|
TFTP() -
Creates a TFTP instance with a default timeout of DEFAULT_TIMEOUT,
a null socket, and buffered operations disabled.
|
void | beginBufferedOps() -
Initializes the internal buffers.
|
TFTPPacket | bufferedReceive() -
This is a special method to perform a more efficient packet receive.
|
void | bufferedSend(TFTPPacket packet) -
This is a special method to perform a more efficient packet send.
|
void | discardPackets() -
This method synchronizes a connection by discarding all packets that
may be in the local socket buffer.
|
void | endBufferedOps() -
Releases the resources used to perform buffered sends and receives.
|
static String | getModeName(int mode) -
Returns the TFTP string representation of a TFTP transfer mode.
|
TFTPPacket | receive() -
Receives a TFTPPacket.
|
void | send(TFTPPacket packet) -
Sends a TFTP packet to its destination.
|
ASCII_MODE
public static final int ASCII_MODE
The ascii transfer mode. Its value is 0 and equivalent to NETASCII_MODE
BINARY_MODE
public static final int BINARY_MODE
The binary transfer mode. Its value is 1 and equivalent to OCTET_MODE.
DEFAULT_PORT
public static final int DEFAULT_PORT
The default TFTP port according to RFC 783 is 69.
DEFAULT_TIMEOUT
public static final int DEFAULT_TIMEOUT
The default number of milliseconds to wait to receive a datagram
before timing out. The default is 5000 milliseconds (5 seconds).
IMAGE_MODE
public static final int IMAGE_MODE
The image transfer mode. Its value is 1 and equivalent to OCTET_MODE.
NETASCII_MODE
public static final int NETASCII_MODE
The netascii transfer mode. Its value is 0.
OCTET_MODE
public static final int OCTET_MODE
The octet transfer mode. Its value is 1.
TFTP
public TFTP()
Creates a TFTP instance with a default timeout of DEFAULT_TIMEOUT,
a null socket, and buffered operations disabled.
beginBufferedOps
public final void beginBufferedOps()
Initializes the internal buffers. Buffers are used by
bufferedSend()
and
bufferedReceive()
. This
method must be called before calling either one of those two
methods. When you finish using buffered operations, you must
call
endBufferedOps()
.
bufferedReceive
public final TFTPPacket bufferedReceive()
throws IOException,
InterruptedIOException,
SocketException,
TFTPPacketException
This is a special method to perform a more efficient packet receive.
It should only be used after calling
beginBufferedOps()
. beginBufferedOps()
initializes a set of buffers used internally that prevent the new
allocation of a DatagramPacket and byte array for each send and receive.
To use these buffers you must call the bufferedReceive() and
bufferedSend() methods instead of send() and receive(). You must
also be certain that you don't manipulate the resulting packet in
such a way that it interferes with future buffered operations.
For example, a TFTPDataPacket received with bufferedReceive() will
have a reference to the internal byte buffer. You must finish using
this data before calling bufferedReceive() again, or else the data
will be overwritten by the the call.
bufferedSend
public final void bufferedSend(TFTPPacket packet)
throws IOException
This is a special method to perform a more efficient packet send.
It should only be used after calling
beginBufferedOps()
. beginBufferedOps()
initializes a set of buffers used internally that prevent the new
allocation of a DatagramPacket and byte array for each send and receive.
To use these buffers you must call the bufferedReceive() and
bufferedSend() methods instead of send() and receive(). You must
also be certain that you don't manipulate the resulting packet in
such a way that it interferes with future buffered operations.
For example, a TFTPDataPacket received with bufferedReceive() will
have a reference to the internal byte buffer. You must finish using
this data before calling bufferedReceive() again, or else the data
will be overwritten by the the call.
packet
- The TFTP packet to send.
discardPackets
public final void discardPackets()
throws IOException
This method synchronizes a connection by discarding all packets that
may be in the local socket buffer. This method need only be called
when you implement your own TFTP client or server.
endBufferedOps
public final void endBufferedOps()
Releases the resources used to perform buffered sends and receives.
getModeName
public static final String getModeName(int mode)
Returns the TFTP string representation of a TFTP transfer mode.
Will throw an ArrayIndexOutOfBoundsException if an invalid transfer
mode is specified.
mode
- The TFTP transfer mode. One of the MODE constants.
- The TFTP string representation of the TFTP transfer mode.
receive
public final TFTPPacket receive()
throws IOException,
InterruptedIOException,
SocketException,
TFTPPacketException
send
public final void send(TFTPPacket packet)
throws IOException
Sends a TFTP packet to its destination.
packet
- The TFTP packet to send.