src/javax/jmdns/impl/DNSOutgoing.java - platform/external/jmdns - Git at Google

 // Copyright 2003-2005 Arthur van Hoff, Rick Blair
 // Licensed under Apache License version 2.0
 // Original license LGPL

 package javax.jmdns.impl;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;

 import javax.jmdns.impl.constants.DNSConstants;
 import javax.jmdns.impl.constants.DNSRecordClass;

 /**
  * An outgoing DNS message.
  *
  * @author Arthur van Hoff, Rick Blair, Werner Randelshofer
  */
 public final class DNSOutgoing extends DNSMessage {

     public static class MessageOutputStream extends ByteArrayOutputStream {
         private final DNSOutgoing _out;

         private final int         _offset;

         /**
          * Creates a new message stream, with a buffer capacity of the specified size, in bytes.
          *
          * @param size
          *            the initial size.
          * @exception IllegalArgumentException
          *                if size is negative.
          */
         MessageOutputStream(int size, DNSOutgoing out) {
             this(size, out, 0);
         }

         MessageOutputStream(int size, DNSOutgoing out, int offset) {
             super(size);
             _out = out;
             _offset = offset;
         }

         void writeByte(int value) {
             this.write(value & 0xFF);
         }

         void writeBytes(String str, int off, int len) {
             for (int i = 0; i < len; i++) {
                 writeByte(str.charAt(off + i));
             }
         }

         void writeBytes(byte data[]) {
             if (data != null) {
                 writeBytes(data, 0, data.length);
             }
         }

         void writeBytes(byte data[], int off, int len) {
             for (int i = 0; i < len; i++) {
                 writeByte(data[off + i]);
             }
         }

         void writeShort(int value) {
             writeByte(value >> 8);
             writeByte(value);
         }

         void writeInt(int value) {
             writeShort(value >> 16);
             writeShort(value);
         }

         void writeUTF(String str, int off, int len) {
             // compute utf length
             int utflen = 0;
             for (int i = 0; i < len; i++) {
                 int ch = str.charAt(off + i);
                 if ((ch >= 0x0001) && (ch <= 0x007F)) {
                     utflen += 1;
                 } else {
                     if (ch > 0x07FF) {
                         utflen += 3;
                     } else {
                         utflen += 2;
                     }
                 }
             }
             // write utf length
             writeByte(utflen);
             // write utf data
             for (int i = 0; i < len; i++) {
                 int ch = str.charAt(off + i);
                 if ((ch >= 0x0001) && (ch <= 0x007F)) {
                     writeByte(ch);
                 } else {
                     if (ch > 0x07FF) {
                         writeByte(0xE0 | ((ch >> 12) & 0x0F));
                         writeByte(0x80 | ((ch >> 6) & 0x3F));
                         writeByte(0x80 | ((ch >> 0) & 0x3F));
                     } else {
                         writeByte(0xC0 | ((ch >> 6) & 0x1F));
                         writeByte(0x80 | ((ch >> 0) & 0x3F));
                     }
                 }
             }
         }

         void writeName(String name) {
             writeName(name, true);
         }

         void writeName(String name, boolean useCompression) {
             String aName = name;
             while (true) {
                 int n = aName.indexOf('.');
                 if (n < 0) {
                     n = aName.length();
                 }
                 if (n <= 0) {
                     writeByte(0);
                     return;
                 }
                 String label = aName.substring(0, n);
                 if (useCompression && USE_DOMAIN_NAME_COMPRESSION) {
                     Integer offset = _out._names.get(aName);
                     if (offset != null) {
                         int val = offset.intValue();
                         writeByte((val >> 8) | 0xC0);
                         writeByte(val & 0xFF);
                         return;
                     }
                     _out._names.put(aName, Integer.valueOf(this.size() + _offset));
                     writeUTF(label, 0, label.length());
                 } else {
                     writeUTF(label, 0, label.length());
                 }
                 aName = aName.substring(n);
                 if (aName.startsWith(".")) {
                     aName = aName.substring(1);
                 }
             }
         }

         void writeQuestion(DNSQuestion question) {
             writeName(question.getName());
             writeShort(question.getRecordType().indexValue());
             writeShort(question.getRecordClass().indexValue());
         }

         void writeRecord(DNSRecord rec, long now) {
             writeName(rec.getName());
             writeShort(rec.getRecordType().indexValue());
             writeShort(rec.getRecordClass().indexValue() | ((rec.isUnique() && _out.isMulticast()) ? DNSRecordClass.CLASS_UNIQUE : 0));
             writeInt((now == 0) ? rec.getTTL() : rec.getRemainingTTL(now));

             // We need to take into account the 2 size bytes
             MessageOutputStream record = new MessageOutputStream(512, _out, _offset + this.size() + 2);
             rec.write(record);
             byte[] byteArray = record.toByteArray();

             writeShort(byteArray.length);
             write(byteArray, 0, byteArray.length);
         }

     }

     /**
      * This can be used to turn off domain name compression. This was helpful for tracking problems interacting with other mdns implementations.
      */
     public static boolean             USE_DOMAIN_NAME_COMPRESSION = true;

     Map<String, Integer>              _names;

     private int                       _maxUDPPayload;

     private final MessageOutputStream _questionsBytes;

     private final MessageOutputStream _answersBytes;

     private final MessageOutputStream _authoritativeAnswersBytes;

     private final MessageOutputStream _additionalsAnswersBytes;

     private final static int          HEADER_SIZE                 = 12;

     /**
      * Create an outgoing multicast query or response.
      *
      * @param flags
      */
     public DNSOutgoing(int flags) {
         this(flags, true, DNSConstants.MAX_MSG_TYPICAL);
     }

     /**
      * Create an outgoing query or response.
      *
      * @param flags
      * @param multicast
      */
     public DNSOutgoing(int flags, boolean multicast) {
         this(flags, multicast, DNSConstants.MAX_MSG_TYPICAL);
     }

     /**
      * Create an outgoing query or response.
      *
      * @param flags
      * @param multicast
      * @param senderUDPPayload
      *            The sender's UDP payload size is the number of bytes of the largest UDP payload that can be reassembled and delivered in the sender's network stack.
      */
     public DNSOutgoing(int flags, boolean multicast, int senderUDPPayload) {
         super(flags, 0, multicast);
         _names = new HashMap<String, Integer>();
         _maxUDPPayload = (senderUDPPayload > 0 ? senderUDPPayload : DNSConstants.MAX_MSG_TYPICAL);
         _questionsBytes = new MessageOutputStream(senderUDPPayload, this);
         _answersBytes = new MessageOutputStream(senderUDPPayload, this);
         _authoritativeAnswersBytes = new MessageOutputStream(senderUDPPayload, this);
         _additionalsAnswersBytes = new MessageOutputStream(senderUDPPayload, this);
     }

     /**
      * Return the number of byte available in the message.
      *
      * @return available space
      */
     public int availableSpace() {
         return _maxUDPPayload - HEADER_SIZE - _questionsBytes.size() - _answersBytes.size() - _authoritativeAnswersBytes.size() - _additionalsAnswersBytes.size();
     }

     /**
      * Add a question to the message.
      *
      * @param rec
      * @exception IOException
      */
     public void addQuestion(DNSQuestion rec) throws IOException {
         MessageOutputStream record = new MessageOutputStream(512, this);
         record.writeQuestion(rec);
         byte[] byteArray = record.toByteArray();
         if (byteArray.length < this.availableSpace()) {
             _questions.add(rec);
             _questionsBytes.write(byteArray, 0, byteArray.length);
         } else {
             throw new IOException("message full");
         }
     }

     /**
      * Add an answer if it is not suppressed.
      *
      * @param in
      * @param rec
      * @exception IOException
      */
     public void addAnswer(DNSIncoming in, DNSRecord rec) throws IOException {
         if ((in == null) || !rec.suppressedBy(in)) {
             this.addAnswer(rec, 0);
         }
     }

     /**
      * Add an answer to the message.
      *
      * @param rec
      * @param now
      * @exception IOException
      */
     public void addAnswer(DNSRecord rec, long now) throws IOException {
         if (rec != null) {
             if ((now == 0) || !rec.isExpired(now)) {
                 MessageOutputStream record = new MessageOutputStream(512, this);
                 record.writeRecord(rec, now);
                 byte[] byteArray = record.toByteArray();
                 if (byteArray.length < this.availableSpace()) {
                     _answers.add(rec);
                     _answersBytes.write(byteArray, 0, byteArray.length);
                 } else {
                     throw new IOException("message full");
                 }
             }
         }
     }

     /**
      * Add an authoritative answer to the message.
      *
      * @param rec
      * @exception IOException
      */
     public void addAuthorativeAnswer(DNSRecord rec) throws IOException {
         MessageOutputStream record = new MessageOutputStream(512, this);
         record.writeRecord(rec, 0);
         byte[] byteArray = record.toByteArray();
         if (byteArray.length < this.availableSpace()) {
             _authoritativeAnswers.add(rec);
             _authoritativeAnswersBytes.write(byteArray, 0, byteArray.length);
         } else {
             throw new IOException("message full");
         }
     }

     /**
      * Add an additional answer to the record. Omit if there is no room.
      *
      * @param in
      * @param rec
      * @exception IOException
      */
     public void addAdditionalAnswer(DNSIncoming in, DNSRecord rec) throws IOException {
         MessageOutputStream record = new MessageOutputStream(512, this);
         record.writeRecord(rec, 0);
         byte[] byteArray = record.toByteArray();
         if (byteArray.length < this.availableSpace()) {
             _additionals.add(rec);
             _additionalsAnswersBytes.write(byteArray, 0, byteArray.length);
         } else {
             throw new IOException("message full");
         }
     }

     /**
      * Builds the final message buffer to be send and returns it.
      *
      * @return bytes to send.
      */
     public byte[] data() {
         long now = System.currentTimeMillis(); // System.currentTimeMillis()
         _names.clear();

         MessageOutputStream message = new MessageOutputStream(_maxUDPPayload, this);
         message.writeShort(_multicast ? 0 : this.getId());
         message.writeShort(this.getFlags());
         message.writeShort(this.getNumberOfQuestions());
         message.writeShort(this.getNumberOfAnswers());
         message.writeShort(this.getNumberOfAuthorities());
         message.writeShort(this.getNumberOfAdditionals());
         for (DNSQuestion question : _questions) {
             message.writeQuestion(question);
         }
         for (DNSRecord record : _answers) {
             message.writeRecord(record, now);
         }
         for (DNSRecord record : _authoritativeAnswers) {
             message.writeRecord(record, now);
         }
         for (DNSRecord record : _additionals) {
             message.writeRecord(record, now);
         }
         return message.toByteArray();
     }

     @Override
     public boolean isQuery() {
         return (this.getFlags() & DNSConstants.FLAGS_QR_MASK) == DNSConstants.FLAGS_QR_QUERY;
     }

     /**
      * Debugging.
      */
     String print(boolean dump) {
         StringBuilder buf = new StringBuilder();
         buf.append(this.print());
         if (dump) {
             buf.append(this.print(this.data()));
         }
         return buf.toString();
     }

     @Override
     public String toString() {
         StringBuffer buf = new StringBuffer();
         buf.append(isQuery() ? "dns[query:" : "dns[response:");
         buf.append(" id=0x");
         buf.append(Integer.toHexString(this.getId()));
         if (this.getFlags() != 0) {
             buf.append(", flags=0x");
             buf.append(Integer.toHexString(this.getFlags()));
             if ((this.getFlags() & DNSConstants.FLAGS_QR_RESPONSE) != 0) {
                 buf.append(":r");
             }
             if ((this.getFlags() & DNSConstants.FLAGS_AA) != 0) {
                 buf.append(":aa");
             }
             if ((this.getFlags() & DNSConstants.FLAGS_TC) != 0) {
                 buf.append(":tc");
             }
         }
         if (this.getNumberOfQuestions() > 0) {
             buf.append(", questions=");
             buf.append(this.getNumberOfQuestions());
         }
         if (this.getNumberOfAnswers() > 0) {
             buf.append(", answers=");
             buf.append(this.getNumberOfAnswers());
         }
         if (this.getNumberOfAuthorities() > 0) {
             buf.append(", authorities=");
             buf.append(this.getNumberOfAuthorities());
         }
         if (this.getNumberOfAdditionals() > 0) {
             buf.append(", additionals=");
             buf.append(this.getNumberOfAdditionals());
         }
         if (this.getNumberOfQuestions() > 0) {
             buf.append("\nquestions:");
             for (DNSQuestion question : _questions) {
                 buf.append("\n\t");
                 buf.append(question);
             }
         }
         if (this.getNumberOfAnswers() > 0) {
             buf.append("\nanswers:");
             for (DNSRecord record : _answers) {
                 buf.append("\n\t");
                 buf.append(record);
             }
         }
         if (this.getNumberOfAuthorities() > 0) {
             buf.append("\nauthorities:");
             for (DNSRecord record : _authoritativeAnswers) {
                 buf.append("\n\t");
                 buf.append(record);
             }
         }
         if (this.getNumberOfAdditionals() > 0) {
             buf.append("\nadditionals:");
             for (DNSRecord record : _additionals) {
                 buf.append("\n\t");
                 buf.append(record);
             }
         }
         buf.append("\nnames=");
         buf.append(_names);
         buf.append("]");
         return buf.toString();
     }

     /**
      * @return the maxUDPPayload
      */
     public int getMaxUDPPayload() {
         return this._maxUDPPayload;
     }

 }
	// Copyright 2003-2005 Arthur van Hoff, Rick Blair
	// Licensed under Apache License version 2.0
	// Original license LGPL

	package javax.jmdns.impl;

	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.util.HashMap;
	import java.util.Map;

	import javax.jmdns.impl.constants.DNSConstants;
	import javax.jmdns.impl.constants.DNSRecordClass;

	/**
	* An outgoing DNS message.
	*
	* @author Arthur van Hoff, Rick Blair, Werner Randelshofer
	*/
	public final class DNSOutgoing extends DNSMessage {

	public static class MessageOutputStream extends ByteArrayOutputStream {
	private final DNSOutgoing _out;

	private final int _offset;

	/**
	* Creates a new message stream, with a buffer capacity of the specified size, in bytes.
	*
	* @param size
	* the initial size.
	* @exception IllegalArgumentException
	* if size is negative.
	*/
	MessageOutputStream(int size, DNSOutgoing out) {
	this(size, out, 0);
	}

	MessageOutputStream(int size, DNSOutgoing out, int offset) {
	super(size);
	_out = out;
	_offset = offset;
	}

	void writeByte(int value) {
	this.write(value & 0xFF);
	}

	void writeBytes(String str, int off, int len) {
	for (int i = 0; i < len; i++) {
	writeByte(str.charAt(off + i));
	}
	}

	void writeBytes(byte data[]) {
	if (data != null) {
	writeBytes(data, 0, data.length);
	}
	}

	void writeBytes(byte data[], int off, int len) {
	for (int i = 0; i < len; i++) {
	writeByte(data[off + i]);
	}
	}

	void writeShort(int value) {
	writeByte(value >> 8);
	writeByte(value);
	}

	void writeInt(int value) {
	writeShort(value >> 16);
	writeShort(value);
	}

	void writeUTF(String str, int off, int len) {
	// compute utf length
	int utflen = 0;
	for (int i = 0; i < len; i++) {
	int ch = str.charAt(off + i);
	if ((ch >= 0x0001) && (ch <= 0x007F)) {
	utflen += 1;
	} else {
	if (ch > 0x07FF) {
	utflen += 3;
	} else {
	utflen += 2;
	}
	}
	}
	// write utf length
	writeByte(utflen);
	// write utf data
	for (int i = 0; i < len; i++) {
	int ch = str.charAt(off + i);
	if ((ch >= 0x0001) && (ch <= 0x007F)) {
	writeByte(ch);
	} else {
	if (ch > 0x07FF) {
	writeByte(0xE0 \| ((ch >> 12) & 0x0F));
	writeByte(0x80 \| ((ch >> 6) & 0x3F));
	writeByte(0x80 \| ((ch >> 0) & 0x3F));
	} else {
	writeByte(0xC0 \| ((ch >> 6) & 0x1F));
	writeByte(0x80 \| ((ch >> 0) & 0x3F));
	}
	}
	}
	}

	void writeName(String name) {
	writeName(name, true);
	}

	void writeName(String name, boolean useCompression) {
	String aName = name;
	while (true) {
	int n = aName.indexOf('.');
	if (n < 0) {
	n = aName.length();
	}
	if (n <= 0) {
	writeByte(0);
	return;
	}
	String label = aName.substring(0, n);
	if (useCompression && USE_DOMAIN_NAME_COMPRESSION) {
	Integer offset = _out._names.get(aName);
	if (offset != null) {
	int val = offset.intValue();
	writeByte((val >> 8) \| 0xC0);
	writeByte(val & 0xFF);
	return;
	}
	_out._names.put(aName, Integer.valueOf(this.size() + _offset));
	writeUTF(label, 0, label.length());
	} else {
	writeUTF(label, 0, label.length());
	}
	aName = aName.substring(n);
	if (aName.startsWith(".")) {
	aName = aName.substring(1);
	}
	}
	}

	void writeQuestion(DNSQuestion question) {
	writeName(question.getName());
	writeShort(question.getRecordType().indexValue());
	writeShort(question.getRecordClass().indexValue());
	}

	void writeRecord(DNSRecord rec, long now) {
	writeName(rec.getName());
	writeShort(rec.getRecordType().indexValue());
	writeShort(rec.getRecordClass().indexValue() \| ((rec.isUnique() && _out.isMulticast()) ? DNSRecordClass.CLASS_UNIQUE : 0));
	writeInt((now == 0) ? rec.getTTL() : rec.getRemainingTTL(now));

	// We need to take into account the 2 size bytes
	MessageOutputStream record = new MessageOutputStream(512, _out, _offset + this.size() + 2);
	rec.write(record);
	byte[] byteArray = record.toByteArray();

	writeShort(byteArray.length);
	write(byteArray, 0, byteArray.length);
	}

	}

	/**
	* This can be used to turn off domain name compression. This was helpful for tracking problems interacting with other mdns implementations.
	*/
	public static boolean USE_DOMAIN_NAME_COMPRESSION = true;

	Map<String, Integer> _names;

	private int _maxUDPPayload;

	private final MessageOutputStream _questionsBytes;

	private final MessageOutputStream _answersBytes;

	private final MessageOutputStream _authoritativeAnswersBytes;

	private final MessageOutputStream _additionalsAnswersBytes;

	private final static int HEADER_SIZE = 12;

	/**
	* Create an outgoing multicast query or response.
	*
	* @param flags
	*/
	public DNSOutgoing(int flags) {
	this(flags, true, DNSConstants.MAX_MSG_TYPICAL);
	}

	/**
	* Create an outgoing query or response.
	*
	* @param flags
	* @param multicast
	*/
	public DNSOutgoing(int flags, boolean multicast) {
	this(flags, multicast, DNSConstants.MAX_MSG_TYPICAL);
	}

	/**
	* Create an outgoing query or response.
	*
	* @param flags
	* @param multicast
	* @param senderUDPPayload
	* The sender's UDP payload size is the number of bytes of the largest UDP payload that can be reassembled and delivered in the sender's network stack.
	*/
	public DNSOutgoing(int flags, boolean multicast, int senderUDPPayload) {
	super(flags, 0, multicast);
	_names = new HashMap<String, Integer>();
	_maxUDPPayload = (senderUDPPayload > 0 ? senderUDPPayload : DNSConstants.MAX_MSG_TYPICAL);
	_questionsBytes = new MessageOutputStream(senderUDPPayload, this);
	_answersBytes = new MessageOutputStream(senderUDPPayload, this);
	_authoritativeAnswersBytes = new MessageOutputStream(senderUDPPayload, this);
	_additionalsAnswersBytes = new MessageOutputStream(senderUDPPayload, this);
	}

	/**
	* Return the number of byte available in the message.
	*
	* @return available space
	*/
	public int availableSpace() {
	return _maxUDPPayload - HEADER_SIZE - _questionsBytes.size() - _answersBytes.size() - _authoritativeAnswersBytes.size() - _additionalsAnswersBytes.size();
	}

	/**
	* Add a question to the message.
	*
	* @param rec
	* @exception IOException
	*/
	public void addQuestion(DNSQuestion rec) throws IOException {
	MessageOutputStream record = new MessageOutputStream(512, this);
	record.writeQuestion(rec);
	byte[] byteArray = record.toByteArray();
	if (byteArray.length < this.availableSpace()) {
	_questions.add(rec);
	_questionsBytes.write(byteArray, 0, byteArray.length);
	} else {
	throw new IOException("message full");
	}
	}

	/**
	* Add an answer if it is not suppressed.
	*
	* @param in
	* @param rec
	* @exception IOException
	*/
	public void addAnswer(DNSIncoming in, DNSRecord rec) throws IOException {
	if ((in == null) \|\| !rec.suppressedBy(in)) {
	this.addAnswer(rec, 0);
	}
	}

	/**
	* Add an answer to the message.
	*
	* @param rec
	* @param now
	* @exception IOException
	*/
	public void addAnswer(DNSRecord rec, long now) throws IOException {
	if (rec != null) {
	if ((now == 0) \|\| !rec.isExpired(now)) {
	MessageOutputStream record = new MessageOutputStream(512, this);
	record.writeRecord(rec, now);
	byte[] byteArray = record.toByteArray();
	if (byteArray.length < this.availableSpace()) {
	_answers.add(rec);
	_answersBytes.write(byteArray, 0, byteArray.length);
	} else {
	throw new IOException("message full");
	}
	}
	}
	}

	/**
	* Add an authoritative answer to the message.
	*
	* @param rec
	* @exception IOException
	*/
	public void addAuthorativeAnswer(DNSRecord rec) throws IOException {
	MessageOutputStream record = new MessageOutputStream(512, this);
	record.writeRecord(rec, 0);
	byte[] byteArray = record.toByteArray();
	if (byteArray.length < this.availableSpace()) {
	_authoritativeAnswers.add(rec);
	_authoritativeAnswersBytes.write(byteArray, 0, byteArray.length);
	} else {
	throw new IOException("message full");
	}
	}

	/**
	* Add an additional answer to the record. Omit if there is no room.
	*
	* @param in
	* @param rec
	* @exception IOException
	*/
	public void addAdditionalAnswer(DNSIncoming in, DNSRecord rec) throws IOException {
	MessageOutputStream record = new MessageOutputStream(512, this);
	record.writeRecord(rec, 0);
	byte[] byteArray = record.toByteArray();
	if (byteArray.length < this.availableSpace()) {
	_additionals.add(rec);
	_additionalsAnswersBytes.write(byteArray, 0, byteArray.length);
	} else {
	throw new IOException("message full");
	}
	}

	/**
	* Builds the final message buffer to be send and returns it.
	*
	* @return bytes to send.
	*/
	public byte[] data() {
	long now = System.currentTimeMillis(); // System.currentTimeMillis()
	_names.clear();

	MessageOutputStream message = new MessageOutputStream(_maxUDPPayload, this);
	message.writeShort(_multicast ? 0 : this.getId());
	message.writeShort(this.getFlags());
	message.writeShort(this.getNumberOfQuestions());
	message.writeShort(this.getNumberOfAnswers());
	message.writeShort(this.getNumberOfAuthorities());
	message.writeShort(this.getNumberOfAdditionals());
	for (DNSQuestion question : _questions) {
	message.writeQuestion(question);
	}
	for (DNSRecord record : _answers) {
	message.writeRecord(record, now);
	}
	for (DNSRecord record : _authoritativeAnswers) {
	message.writeRecord(record, now);
	}
	for (DNSRecord record : _additionals) {
	message.writeRecord(record, now);
	}
	return message.toByteArray();
	}

	@Override
	public boolean isQuery() {
	return (this.getFlags() & DNSConstants.FLAGS_QR_MASK) == DNSConstants.FLAGS_QR_QUERY;
	}

	/**
	* Debugging.
	*/
	String print(boolean dump) {
	StringBuilder buf = new StringBuilder();
	buf.append(this.print());
	if (dump) {
	buf.append(this.print(this.data()));
	}
	return buf.toString();
	}

	@Override
	public String toString() {
	StringBuffer buf = new StringBuffer();
	buf.append(isQuery() ? "dns[query:" : "dns[response:");
	buf.append(" id=0x");
	buf.append(Integer.toHexString(this.getId()));
	if (this.getFlags() != 0) {
	buf.append(", flags=0x");
	buf.append(Integer.toHexString(this.getFlags()));
	if ((this.getFlags() & DNSConstants.FLAGS_QR_RESPONSE) != 0) {
	buf.append(":r");
	}
	if ((this.getFlags() & DNSConstants.FLAGS_AA) != 0) {
	buf.append(":aa");
	}
	if ((this.getFlags() & DNSConstants.FLAGS_TC) != 0) {
	buf.append(":tc");
	}
	}
	if (this.getNumberOfQuestions() > 0) {
	buf.append(", questions=");
	buf.append(this.getNumberOfQuestions());
	}
	if (this.getNumberOfAnswers() > 0) {
	buf.append(", answers=");
	buf.append(this.getNumberOfAnswers());
	}
	if (this.getNumberOfAuthorities() > 0) {
	buf.append(", authorities=");
	buf.append(this.getNumberOfAuthorities());
	}
	if (this.getNumberOfAdditionals() > 0) {
	buf.append(", additionals=");
	buf.append(this.getNumberOfAdditionals());
	}
	if (this.getNumberOfQuestions() > 0) {
	buf.append("\nquestions:");
	for (DNSQuestion question : _questions) {
	buf.append("\n\t");
	buf.append(question);
	}
	}
	if (this.getNumberOfAnswers() > 0) {
	buf.append("\nanswers:");
	for (DNSRecord record : _answers) {
	buf.append("\n\t");
	buf.append(record);
	}
	}
	if (this.getNumberOfAuthorities() > 0) {
	buf.append("\nauthorities:");
	for (DNSRecord record : _authoritativeAnswers) {
	buf.append("\n\t");
	buf.append(record);
	}
	}
	if (this.getNumberOfAdditionals() > 0) {
	buf.append("\nadditionals:");
	for (DNSRecord record : _additionals) {
	buf.append("\n\t");
	buf.append(record);
	}
	}
	buf.append("\nnames=");
	buf.append(_names);
	buf.append("]");
	return buf.toString();
	}

	/**
	* @return the maxUDPPayload
	*/
	public int getMaxUDPPayload() {
	return this._maxUDPPayload;
	}

	}