org.apache.commons.net.tftp
Class TFTPAckPacket

java.lang.Object
  extended byorg.apache.commons.net.tftp.TFTPPacket
      extended byorg.apache.commons.net.tftp.TFTPAckPacket

public final class TFTPAckPacket
extends TFTPPacket

A final class derived from TFTPPacket definiing 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.

Author:
Daniel F. Savarese
See Also:
TFTPPacket, TFTPPacketException, TFTP

Field Summary
(package private)  int _blockNumber
          The block number being acknowledged by the packet.
 
Fields inherited from class org.apache.commons.net.tftp.TFTPPacket
_address, _port, _type, ACKNOWLEDGEMENT, DATA, ERROR, MIN_PACKET_SIZE, READ_REQUEST, SEGMENT_SIZE, WRITE_REQUEST
 
Constructor Summary
(package private) TFTPAckPacket(java.net.DatagramPacket datagram)
          Creates an acknowledgement packet based from a received datagram.
  TFTPAckPacket(java.net.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
(package private)  java.net.DatagramPacket _newDatagram(java.net.DatagramPacket datagram, byte[] data)
          This is a method only available within the package for implementing efficient datagram transport by elminating buffering.
 int getBlockNumber()
          Returns the block number of the acknowledgement.
 java.net.DatagramPacket newDatagram()
          Creates a UDP datagram containing all the TFTP acknowledgement packet data in the proper format.
 void setBlockNumber(int blockNumber)
          Sets the block number of the acknowledgement.
 
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, toString, wait, wait, wait
 

Field Detail

_blockNumber

int _blockNumber
The block number being acknowledged by the packet.

Constructor Detail

TFTPAckPacket

public TFTPAckPacket(java.net.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.

TFTPAckPacket

TFTPAckPacket(java.net.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.
Method Detail

_newDatagram

java.net.DatagramPacket _newDatagram(java.net.DatagramPacket datagram,
                                     byte[] data)
This is a method only available within the package for implementing efficient datagram transport by elminating 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.

newDatagram

public java.net.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.

getBlockNumber

public int getBlockNumber()
Returns the block number of the acknowledgement.

Returns:
The block number of the acknowledgement.

setBlockNumber

public void setBlockNumber(int blockNumber)
Sets the block number of the acknowledgement.