org.apache.commons.net.tftp

Class TFTPDataPacket

java.lang.Object

org.apache.commons.net.tftp.TFTPPacket

org.apache.commons.net.tftp.TFTPDataPacket

public final class TFTPDataPacket
extends TFTPPacket

A final class derived from TFTPPacket defining the TFTP Data packet type.

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. Additionally, only very few people should have to care about any of the TFTPPacket classes or derived classes. Almost all users should only be concerned with the TFTPClient class receiveFile() and sendFile() methods.

See Also:

TFTPPacket, TFTPPacketException, TFTP

Field Summary

Fields

Modifier and Type	Field and Description
(package private) int	blockNumber The block number of the packet.
static int	MAX_DATA_LENGTH The maximum number of bytes in a TFTP data packet (512)
static int	MIN_DATA_LENGTH The minimum number of bytes in a TFTP data packet (0)

Fields inherited from class org.apache.commons.net.tftp.TFTPPacket

ACKNOWLEDGEMENT, address, DATA, ERROR, MIN_PACKET_SIZE, OACK, port, READ_REQUEST, SEGMENT_SIZE, type, WRITE_REQUEST

Constructor Summary

Constructors

Constructor and Description
TFTPDataPacket(DatagramPacket datagram) Creates a data packet based from a received datagram.
TFTPDataPacket(InetAddress destination, int port, int blockNumber, byte[] data) Creates a data packet to be sent to a host at a given port with a given block number.
TFTPDataPacket(InetAddress destination, int port, int blockNumber, byte[] data, int offset, int length) Creates a data packet to be sent to a host at a given port with a given block number.

Method Summary

Modifier and Type	Method and Description
int	getBlockNumber() Gets the block number of the data packet.
byte[]	getData() Gets the byte array containing the packet data.
int	getDataLength() Gets the length of the data part of the data packet.
int	getDataOffset() Gets the offset into the byte array where the packet data actually starts.
DatagramPacket	newDatagram() Creates a UDP datagram containing all the TFTP data packet data in the proper format.
(package private) DatagramPacket	newDatagram(DatagramPacket datagram, byte[] data) This is a method only available within the package for implementing efficient datagram transport by eliminating buffering.
void	setBlockNumber(int blockNumber) Sets the block number of the data packet.
void	setData(byte[] data, int offset, int length) Sets the data for the data packet.
String	toString() For debugging

Methods inherited from class org.apache.commons.net.tftp.TFTPPacket

getAddress, getPort, getType, newTFTPPacket, setAddress, setPort

Methods inherited from class java.lang.Object

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

Field Detail

blockNumber

int blockNumber

The block number of the packet.

MAX_DATA_LENGTH

public static final int MAX_DATA_LENGTH

The maximum number of bytes in a TFTP data packet (512)

See Also:

Constant Field Values

MIN_DATA_LENGTH

public static final int MIN_DATA_LENGTH

The minimum number of bytes in a TFTP data packet (0)

See Also:

Constant Field Values

Constructor Detail

TFTPDataPacket

TFTPDataPacket(DatagramPacket datagram)
        throws TFTPPacketException

Creates a data packet based from a received datagram. Assumes the datagram is at least length 4, else an ArrayIndexOutOfBoundsException may be thrown.

Parameters:

datagram - The datagram containing the received data.

Throws:

TFTPPacketException - If the datagram isn't a valid TFTP data packet.

TFTPDataPacket

public TFTPDataPacket(InetAddress destination,
                      int port,
                      int blockNumber,
                      byte[] data)

Creates a data packet to be sent to a host at a given port with a given block number. The actual data to be sent is passed as an array, an offset, and a length. The offset is the offset into the byte array where the data starts. The length is the length of the data.

Parameters:

destination - The host to which the packet is going to be sent.

port - The port to which the packet is going to be sent.

blockNumber - The block number of the data.

data - The byte array containing the data.

TFTPDataPacket

public TFTPDataPacket(InetAddress destination,
                      int port,
                      int blockNumber,
                      byte[] data,
                      int offset,
                      int length)

Creates a data packet to be sent to a host at a given port with a given block number. The actual data to be sent is passed as an array, an offset, and a length. The offset is the offset into the byte array where the data starts. The length is the length of the data.

Parameters:

destination - The host to which the packet is going to be sent.

port - The port to which the packet is going to be sent.

blockNumber - The block number of the data.

data - The byte array containing the data.

offset - The offset into the array where the data starts.

length - The length of the data.

Method Detail

getBlockNumber

public int getBlockNumber()

Gets the block number of the data packet.

Returns:

The block number of the data packet.

getData

public byte[] getData()

Gets the byte array containing the packet data.

Returns:

The byte array containing the packet data.

getDataLength

public int getDataLength()

Gets the length of the data part of the data packet.

Returns:

The length of the data part of the data packet.

getDataOffset

public int getDataOffset()

Gets the offset into the byte array where the packet data actually starts.

Returns:

The offset into the byte array where the packet data actually starts.

newDatagram

public DatagramPacket newDatagram()

Creates a UDP datagram containing all the TFTP data packet data in the proper format. This is a method exposed to the programmer in case he wants to implement his own TFTP client instead of using the TFTPClient class. Under normal circumstances, you should not have a need to call this method.

Specified by:

newDatagram in class TFTPPacket

Returns:

A UDP datagram containing the TFTP data packet.

newDatagram

DatagramPacket newDatagram(DatagramPacket datagram,
                           byte[] data)

This is a method only available within the package for implementing efficient datagram transport by eliminating buffering. It takes a datagram as an argument, and a byte buffer in which to store the raw datagram data. Inside the method, the data is set as the datagram's data and the datagram returned.

Specified by:

newDatagram in class TFTPPacket

Parameters:

datagram - The datagram to create.

data - The buffer to store the packet and to use in the datagram.

Returns:

The datagram argument.

setBlockNumber

public void setBlockNumber(int blockNumber)

Sets the block number of the data packet.

Parameters:

blockNumber - the number to set

setData

public void setData(byte[] data,
                    int offset,
                    int length)

Sets the data for the data packet.

Parameters:

data - The byte array containing the data.

offset - The offset into the array where the data starts.

length - The length of the data.

toString

public String toString()

For debugging

Overrides:

toString in class TFTPPacket