ORO, Inc. Logo  All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class com.oroinc.net.tftp.TFTP

java.lang.Object
   |
   +----com.oroinc.net.DatagramSocketClient
           |
           +----com.oroinc.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.

Copyright © 1997 Original Reusable Objects, Inc. All rights reserved.

See Also:
DatagramSocketClient, TFTPPacket, TFTPPacketException, TFTPClient

Variable Index

 o ASCII_MODE
The ascii transfer mode.
 o BINARY_MODE
The binary transfer mode.
 o DEFAULT_PORT
The default TFTP port according to RFC 783 is 69.
 o DEFAULT_TIMEOUT
The default number of milliseconds to wait to receive a datagram before timing out.
 o IMAGE_MODE
The image transfer mode.
 o NETASCII_MODE
The netascii transfer mode.
 o OCTET_MODE
The octet transfer mode.

Constructor Index

 o TFTP()
Creates a TFTP instance with a default timeout of DEFAULT_TIMEOUT, a null socket, and buffered operations disabled.

Method Index

 o beginBufferedOps()
Initializes the internal buffers used by bufferedSend() and bufferedReceive() .
 o bufferedReceive()
This is a special method to perform a more efficient packet receive.
 o bufferedSend(TFTPPacket)
This is a special method to perform a more efficient packet send.
 o discardPackets()
This method synchronizes a connection by discarding all packets that may be in the local socket buffer.
 o endBufferedOps()
Releases the resources used to perform buffered sends and receives.
 o getModeName(int)
Returns the TFTP string representation of a TFTP transfer mode.
 o receive()
Receives a TFTPPacket.
 o send(TFTPPacket)
Sends a TFTP packet to its destination.

Variables

 o ASCII_MODE
 public static final int ASCII_MODE
The ascii transfer mode. Its value is 0 and equivalent to NETASCII_MODE

 o NETASCII_MODE
 public static final int NETASCII_MODE
The netascii transfer mode. Its value is 0.

 o BINARY_MODE
 public static final int BINARY_MODE
The binary transfer mode. Its value is 1 and equivalent to OCTET_MODE.

 o IMAGE_MODE
 public static final int IMAGE_MODE
The image transfer mode. Its value is 1 and equivalent to OCTET_MODE.

 o OCTET_MODE
 public static final int OCTET_MODE
The octet transfer mode. Its value is 1.

 o 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).

 o DEFAULT_PORT
 public static final int DEFAULT_PORT
The default TFTP port according to RFC 783 is 69.

Constructors

 o TFTP
 public TFTP()
Creates a TFTP instance with a default timeout of DEFAULT_TIMEOUT, a null socket, and buffered operations disabled.

Methods

 o 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.

Parameters:
mode - The TFTP transfer mode. One of the MODE constants.
Returns:
The TFTP string representation of the TFTP transfer mode.
 o 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.

Throws: IOException
if an I/O error occurs.
 o 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.

Returns:
The TFTPPacket received.
Throws: InterruptedIOException
If a socket timeout occurs. The Java documentation claims an InterruptedIOException is thrown on a DatagramSocket timeout, but in practice we find a SocketException is thrown. You should catch both to be safe.
Throws: SocketException
If a socket timeout occurs. The Java documentation claims an InterruptedIOException is thrown on a DatagramSocket timeout, but in practice we find a SocketException is thrown. You should catch both to be safe.
Throws: IOException
If some other I/O error occurs.
Throws: TFTPPacketException
If an invalid TFTP packet is received.
 o 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.

Parameters:
TFTPPacket - The TFTP packet to send.
Throws: IOException
If some I/O error occurs.
 o beginBufferedOps
 public final void beginBufferedOps()
Initializes the internal buffers 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() .

 o endBufferedOps
 public final void endBufferedOps()
Releases the resources used to perform buffered sends and receives.

 o send
 public final void send(TFTPPacket packet) throws IOException
Sends a TFTP packet to its destination.

Parameters:
TFTPPacket - The TFTP packet to send.
Throws: IOException
If some I/O error occurs.
 o receive
 public final TFTPPacket receive() throws IOException, InterruptedIOException, SocketException, TFTPPacketException
Receives a TFTPPacket.

Returns:
The TFTPPacket received.
Throws: InterruptedIOException
If a socket timeout occurs. The Java documentation claims an InterruptedIOException is thrown on a DatagramSocket timeout, but in practice we find a SocketException is thrown. You should catch both to be safe.
Throws: SocketException
If a socket timeout occurs. The Java documentation claims an InterruptedIOException is thrown on a DatagramSocket timeout, but in practice we find a SocketException is thrown. You should catch both to be safe.
Throws: IOException
If some other I/O error occurs.
Throws: TFTPPacketException
If an invalid TFTP packet is received.

ORO, Inc. Logo  All Packages  Class Hierarchy  This Package  Previous  Next  Index