org.apache.commons.net.tftp

Class TFTPAckPacket

java.lang.Object

org.apache.commons.net.tftp.TFTPPacket

org.apache.commons.net.tftp.TFTPAckPacket

public final class TFTPAckPacket
extends TFTPPacket

A final class derived from TFTPPacket defining the TFTP Acknowledgement 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 being acknowledged by the packet.

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
TFTPAckPacket(DatagramPacket datagram) Creates an acknowledgement packet based from a received datagram.
TFTPAckPacket(InetAddress destination, int port, int blockNumber) Creates an acknowledgment packet to be sent to a host at a given port acknowledging receipt of a block.

Method Summary

Modifier and Type	Method and Description
int	getBlockNumber() Gets the block number of the acknowledgement.
DatagramPacket	newDatagram() Creates a UDP datagram containing all the TFTP acknowledgement 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 acknowledgement.
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 being acknowledged by the packet.

Constructor Detail

TFTPAckPacket

TFTPAckPacket(DatagramPacket datagram)
       throws TFTPPacketException

Creates an acknowledgement 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 acknowledgement.

Throws:

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

TFTPAckPacket

public TFTPAckPacket(InetAddress destination,
                     int port,
                     int blockNumber)

Creates an acknowledgment packet to be sent to a host at a given port acknowledging receipt of a block.

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 being acknowledged.

Method Detail

getBlockNumber

public int getBlockNumber()

Gets the block number of the acknowledgement.

Returns:

The block number of the acknowledgement.

newDatagram

public DatagramPacket newDatagram()

Creates a UDP datagram containing all the TFTP acknowledgement 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 acknowledgement 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 acknowledgement.

Parameters:

blockNumber - the number to set

toString

public String toString()

For debugging

Overrides:

toString in class TFTPPacket