Package org.apache.commons.net.tftp
Class TFTP
java.lang.Object
org.apache.commons.net.DatagramSocketClient
org.apache.commons.net.tftp.TFTP
- All Implemented Interfaces:
- AutoCloseable
- Direct Known Subclasses:
- TFTPClient
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.
- See Also:
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Field SummaryFieldsModifier and TypeFieldDescriptionstatic final intThe ASCII transfer mode.static final intThe binary transfer mode.static final intThe default TFTP port according to RFC 783 is 69.static final intDeprecated.static final DurationThe default duration to wait to receive a datagram before timing out.static final intThe image transfer mode.static final intThe netascii transfer mode.static final intThe octet transfer mode.Fields inherited from class org.apache.commons.net.DatagramSocketClient_isOpen_, _socket_, _socketFactory_, _timeout_
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Constructor SummaryConstructorsConstructorDescriptionTFTP()Creates a TFTP instance with a default timeout ofDEFAULT_TIMEOUT_DURATION, a null socket, and buffered operations disabled.
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Method SummaryModifier and TypeMethodDescriptionfinal voidInitializes the internal buffers.final TFTPPacketThis is a special method to perform a more efficient packet receive.final voidbufferedSend(TFTPPacket packet) This is a special method to perform a more efficient packet send.final voidThis method synchronizes a connection by discarding all packets that may be in the local socket buffer.final voidReleases the resources used to perform buffered sends and receives.static final StringgetModeName(int mode) Returns the TFTP string representation of a TFTP transfer mode.final TFTPPacketreceive()Receives a TFTPPacket.final voidsend(TFTPPacket packet) Sends a TFTP packet to its destination.protected voidtrace(String direction, TFTPPacket packet) Trace facility; this implementation does nothing.Methods inherited from class org.apache.commons.net.DatagramSocketClientcheckOpen, close, getCharset, getCharsetName, getDefaultTimeout, getLocalAddress, getLocalPort, getSoTimeout, getSoTimeoutDuration, isOpen, open, open, open, setCharset, setDatagramSocketFactory, setDefaultTimeout, setDefaultTimeout, setSoTimeout, setSoTimeout
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Field Details- 
ASCII_MODEThe ASCII transfer mode. Its value is 0 and equivalent to NETASCII_MODE- See Also:
 
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NETASCII_MODEThe netascii transfer mode. Its value is 0.- See Also:
 
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BINARY_MODEThe binary transfer mode. Its value is 1 and equivalent to OCTET_MODE.- See Also:
 
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IMAGE_MODEThe image transfer mode. Its value is 1 and equivalent to OCTET_MODE.- See Also:
 
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OCTET_MODEThe octet transfer mode. Its value is 1.- See Also:
 
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DEFAULT_TIMEOUTDeprecated.The default number of milliseconds to wait to receive a datagram before timing out. The default is 5,000 milliseconds (5 seconds).- See Also:
 
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DEFAULT_TIMEOUT_DURATIONThe default duration to wait to receive a datagram before timing out. The default is 5 seconds.- Since:
- 3.10.0
 
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DEFAULT_PORTThe default TFTP port according to RFC 783 is 69.- See Also:
 
 
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Constructor Details- 
TFTPpublic TFTP()Creates a TFTP instance with a default timeout ofDEFAULT_TIMEOUT_DURATION, a null socket, and buffered operations disabled.
 
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Method Details- 
getModeNameReturns 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.
 
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beginBufferedOpsInitializes the internal buffers. Buffers are used bybufferedSend()andbufferedReceive(). This method must be called before calling either one of those two methods. When you finish using buffered operations, you must callendBufferedOps().
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bufferedReceivepublic final TFTPPacket bufferedReceive() throws IOException, InterruptedIOException, SocketException, TFTPPacketExceptionThis is a special method to perform a more efficient packet receive. It should only be used after callingbeginBufferedOps(). 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 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.
- 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.
- IOException- If some other I/O error occurs.
- TFTPPacketException- If an invalid TFTP packet is received.
 
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bufferedSendThis is a special method to perform a more efficient packet send. It should only be used after callingbeginBufferedOps(). 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 call.- Parameters:
- packet- The TFTP packet to send.
- Throws:
- IOException- If some I/O error occurs.
 
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discardPacketsThis 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.
 
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endBufferedOpsReleases the resources used to perform buffered sends and receives.
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receivepublic final TFTPPacket receive() throws IOException, InterruptedIOException, SocketException, TFTPPacketExceptionReceives 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.
- 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.
- IOException- If some other I/O error occurs.
- TFTPPacketException- If an invalid TFTP packet is received.
 
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sendSends a TFTP packet to its destination.- Parameters:
- packet- The TFTP packet to send.
- Throws:
- IOException- If some I/O error occurs.
 
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traceTrace facility; this implementation does nothing.Override it to trace the data, for example: 
 System.out.println(direction + " " + packet.toString());- Parameters:
- direction-- >or- <
- packet- the packet to be sent or that has been received respectively
- Since:
- 3.6
 
 
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DEFAULT_TIMEOUT_DURATION.