src/main/java/org/apache/commons/net/tftp/TFTPRequestPacket.java - commons-net - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package org.apache.commons.net.tftp;

 import java.net.DatagramPacket;
 import java.net.InetAddress;
 import java.nio.charset.Charset;

 /**
  * An abstract class derived from TFTPPacket definiing a TFTP Request packet type. It is subclassed by the
  * {@link org.apache.commons.net.tftp.TFTPReadRequestPacket} and {@link org.apache.commons.net.tftp.TFTPWriteRequestPacket} classes.
  * <p>
  * 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 {@link org.apache.commons.net.tftp.TFTPClient} class {@link org.apache.commons.net.tftp.TFTPClient#receiveFile
  * receiveFile()} and {@link org.apache.commons.net.tftp.TFTPClient#sendFile sendFile()} methods.
  *
  *
  * @see TFTPPacket
  * @see TFTPReadRequestPacket
  * @see TFTPWriteRequestPacket
  * @see TFTPPacketException
  * @see TFTP
  */

 public abstract class TFTPRequestPacket extends TFTPPacket {
     /**
      * An array containing the string names of the transfer modes and indexed by the transfer mode constants.
      */
     static final String[] modeStrings = { "netascii", "octet" };

     /**
      * A null terminated byte array representation of the ASCII names of the transfer mode constants. This is convenient for creating the TFTP request packets.
      */
     private static final byte[] modeBytes[] = { { (byte) 'n', (byte) 'e', (byte) 't', (byte) 'a', (byte) 's', (byte) 'c', (byte) 'i', (byte) 'i', 0 },
             { (byte) 'o', (byte) 'c', (byte) 't', (byte) 'e', (byte) 't', 0 } };

     /** The transfer mode of the request. */
     private final int mode;

     /** The file name of the request. */
     private final String fileName;

     /**
      * Creates a request packet of a given type to be sent to a host at a given port with a file name and transfer mode request.
      *
      * @param destination The host to which the packet is going to be sent.
      * @param port        The port to which the packet is going to be sent.
      * @param type        The type of the request (either TFTPPacket.READ_REQUEST or TFTPPacket.WRITE_REQUEST).
      * @param fileName    The requested file name.
      * @param mode        The requested transfer mode. This should be on of the TFTP class MODE constants (e.g., TFTP.NETASCII_MODE).
      */
     TFTPRequestPacket(final InetAddress destination, final int port, final int type, final String fileName, final int mode) {
         super(type, destination, port);

         this.fileName = fileName;
         this.mode = mode;
     }

     /**
      * Creates a request packet of a given type based on a received datagram. Assumes the datagram is at least length 4, else an ArrayIndexOutOfBoundsException
      * may be thrown.
      *
      * @param type     The type of the request (either TFTPPacket.READ_REQUEST or TFTPPacket.WRITE_REQUEST).
      * @param datagram The datagram containing the received request.
      * @throws TFTPPacketException If the datagram isn't a valid TFTP request packet of the appropriate type.
      */
     TFTPRequestPacket(final int type, final DatagramPacket datagram) throws TFTPPacketException {
         super(type, datagram.getAddress(), datagram.getPort());

         final byte[] data = datagram.getData();

         if (getType() != data[1]) {
             throw new TFTPPacketException("TFTP operator code does not match type.");
         }

         final StringBuilder buffer = new StringBuilder();

         int index = 2;
         int length = datagram.getLength();

         while (index < length && data[index] != 0) {
             buffer.append((char) data[index]);
             ++index;
         }

         this.fileName = buffer.toString();

         if (index >= length) {
             throw new TFTPPacketException("Bad file name and mode format.");
         }

         buffer.setLength(0);
         ++index; // need to advance beyond the end of string marker
         while (index < length && data[index] != 0) {
             buffer.append((char) data[index]);
             ++index;
         }

         final String modeString = buffer.toString().toLowerCase(java.util.Locale.ENGLISH);
         length = modeStrings.length;

         int mode = 0;
         for (index = 0; index < length; index++) {
             if (modeString.equals(modeStrings[index])) {
                 mode = index;
                 break;
             }
         }

         this.mode = mode;

         if (index >= length) {
             throw new TFTPPacketException("Unrecognized TFTP transfer mode: " + modeString);
             // May just want to default to binary mode instead of throwing
             // exception.
             // _mode = TFTP.OCTET_MODE;
         }
     }

     /**
      * Returns the requested file name.
      *
      * @return The requested file name.
      */
     public final String getFilename() {
         return fileName;
     }

     /**
      * Returns the transfer mode of the request.
      *
      * @return The transfer mode of the request.
      */
     public final int getMode() {
         return mode;
     }

     /**
      * Creates a UDP datagram containing all the TFTP request 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 {@link org.apache.commons.net.tftp.TFTPClient} class. Under normal circumstances, you should not have
      * a need to call this method.
      *
      * @return A UDP datagram containing the TFTP request packet.
      */
     @Override
     public final DatagramPacket newDatagram() {
         final int fileLength;
         final int modeLength;
         final byte[] data;

         fileLength = fileName.length();
         modeLength = modeBytes[mode].length;

         data = new byte[fileLength + modeLength + 4];
         data[0] = 0;
         data[1] = (byte) type;
         System.arraycopy(fileName.getBytes(Charset.defaultCharset()), 0, data, 2, fileLength);
         data[fileLength + 2] = 0;
         System.arraycopy(modeBytes[mode], 0, data, fileLength + 3, modeLength);

         return new DatagramPacket(data, data.length, address, port);
     }

     /**
      * 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.
      *
      * @param datagram The datagram to create.
      * @param data     The buffer to store the packet and to use in the datagram.
      * @return The datagram argument.
      */
     @Override
     final DatagramPacket newDatagram(final DatagramPacket datagram, final byte[] data) {
         final int fileLength;
         final int modeLength;

         fileLength = fileName.length();
         modeLength = modeBytes[mode].length;

         data[0] = 0;
         data[1] = (byte) type;
         System.arraycopy(fileName.getBytes(Charset.defaultCharset()), 0, data, 2, fileLength);
         data[fileLength + 2] = 0;
         System.arraycopy(modeBytes[mode], 0, data, fileLength + 3, modeLength);

         datagram.setAddress(address);
         datagram.setPort(port);
         datagram.setData(data);
         datagram.setLength(fileLength + modeLength + 3);

         return datagram;
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package org.apache.commons.net.tftp;

	import java.net.DatagramPacket;
	import java.net.InetAddress;
	import java.nio.charset.Charset;

	/**
	* An abstract class derived from TFTPPacket definiing a TFTP Request packet type. It is subclassed by the
	* {@link org.apache.commons.net.tftp.TFTPReadRequestPacket} and {@link org.apache.commons.net.tftp.TFTPWriteRequestPacket} classes.
	* <p>
	* 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 {@link org.apache.commons.net.tftp.TFTPClient} class {@link org.apache.commons.net.tftp.TFTPClient#receiveFile
	* receiveFile()} and {@link org.apache.commons.net.tftp.TFTPClient#sendFile sendFile()} methods.
	*
	*
	* @see TFTPPacket
	* @see TFTPReadRequestPacket
	* @see TFTPWriteRequestPacket
	* @see TFTPPacketException
	* @see TFTP
	*/

	public abstract class TFTPRequestPacket extends TFTPPacket {
	/**
	* An array containing the string names of the transfer modes and indexed by the transfer mode constants.
	*/
	static final String[] modeStrings = { "netascii", "octet" };

	/**
	* A null terminated byte array representation of the ASCII names of the transfer mode constants. This is convenient for creating the TFTP request packets.
	*/
	private static final byte[] modeBytes[] = { { (byte) 'n', (byte) 'e', (byte) 't', (byte) 'a', (byte) 's', (byte) 'c', (byte) 'i', (byte) 'i', 0 },
	{ (byte) 'o', (byte) 'c', (byte) 't', (byte) 'e', (byte) 't', 0 } };

	/** The transfer mode of the request. */
	private final int mode;

	/** The file name of the request. */
	private final String fileName;

	/**
	* Creates a request packet of a given type to be sent to a host at a given port with a file name and transfer mode request.
	*
	* @param destination The host to which the packet is going to be sent.
	* @param port The port to which the packet is going to be sent.
	* @param type The type of the request (either TFTPPacket.READ_REQUEST or TFTPPacket.WRITE_REQUEST).
	* @param fileName The requested file name.
	* @param mode The requested transfer mode. This should be on of the TFTP class MODE constants (e.g., TFTP.NETASCII_MODE).
	*/
	TFTPRequestPacket(final InetAddress destination, final int port, final int type, final String fileName, final int mode) {
	super(type, destination, port);

	this.fileName = fileName;
	this.mode = mode;
	}

	/**
	* Creates a request packet of a given type based on a received datagram. Assumes the datagram is at least length 4, else an ArrayIndexOutOfBoundsException
	* may be thrown.
	*
	* @param type The type of the request (either TFTPPacket.READ_REQUEST or TFTPPacket.WRITE_REQUEST).
	* @param datagram The datagram containing the received request.
	* @throws TFTPPacketException If the datagram isn't a valid TFTP request packet of the appropriate type.
	*/
	TFTPRequestPacket(final int type, final DatagramPacket datagram) throws TFTPPacketException {
	super(type, datagram.getAddress(), datagram.getPort());

	final byte[] data = datagram.getData();

	if (getType() != data[1]) {
	throw new TFTPPacketException("TFTP operator code does not match type.");
	}

	final StringBuilder buffer = new StringBuilder();

	int index = 2;
	int length = datagram.getLength();

	while (index < length && data[index] != 0) {
	buffer.append((char) data[index]);
	++index;
	}

	this.fileName = buffer.toString();

	if (index >= length) {
	throw new TFTPPacketException("Bad file name and mode format.");
	}

	buffer.setLength(0);
	++index; // need to advance beyond the end of string marker
	while (index < length && data[index] != 0) {
	buffer.append((char) data[index]);
	++index;
	}

	final String modeString = buffer.toString().toLowerCase(java.util.Locale.ENGLISH);
	length = modeStrings.length;

	int mode = 0;
	for (index = 0; index < length; index++) {
	if (modeString.equals(modeStrings[index])) {
	mode = index;
	break;
	}
	}

	this.mode = mode;

	if (index >= length) {
	throw new TFTPPacketException("Unrecognized TFTP transfer mode: " + modeString);
	// May just want to default to binary mode instead of throwing
	// exception.
	// _mode = TFTP.OCTET_MODE;
	}
	}

	/**
	* Returns the requested file name.
	*
	* @return The requested file name.
	*/
	public final String getFilename() {
	return fileName;
	}

	/**
	* Returns the transfer mode of the request.
	*
	* @return The transfer mode of the request.
	*/
	public final int getMode() {
	return mode;
	}

	/**
	* Creates a UDP datagram containing all the TFTP request 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 {@link org.apache.commons.net.tftp.TFTPClient} class. Under normal circumstances, you should not have
	* a need to call this method.
	*
	* @return A UDP datagram containing the TFTP request packet.
	*/
	@Override
	public final DatagramPacket newDatagram() {
	final int fileLength;
	final int modeLength;
	final byte[] data;

	fileLength = fileName.length();
	modeLength = modeBytes[mode].length;

	data = new byte[fileLength + modeLength + 4];
	data[0] = 0;
	data[1] = (byte) type;
	System.arraycopy(fileName.getBytes(Charset.defaultCharset()), 0, data, 2, fileLength);
	data[fileLength + 2] = 0;
	System.arraycopy(modeBytes[mode], 0, data, fileLength + 3, modeLength);

	return new DatagramPacket(data, data.length, address, port);
	}

	/**
	* 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.
	*
	* @param datagram The datagram to create.
	* @param data The buffer to store the packet and to use in the datagram.
	* @return The datagram argument.
	*/
	@Override
	final DatagramPacket newDatagram(final DatagramPacket datagram, final byte[] data) {
	final int fileLength;
	final int modeLength;

	fileLength = fileName.length();
	modeLength = modeBytes[mode].length;

	data[0] = 0;
	data[1] = (byte) type;
	System.arraycopy(fileName.getBytes(Charset.defaultCharset()), 0, data, 2, fileLength);
	data[fileLength + 2] = 0;
	System.arraycopy(modeBytes[mode], 0, data, fileLength + 3, modeLength);

	datagram.setAddress(address);
	datagram.setPort(port);
	datagram.setData(data);
	datagram.setLength(fileLength + modeLength + 3);

	return datagram;
	}
	}