trunk/activemq-jmdns_1.0/src/main/java/org/apache/activemq/jmdns/ServiceInfo.java - activemq - Git at Google

 /**
  * Copyright 2003-2005 Arthur van Hoff, Rick Blair
  *
  * 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.activemq.jmdns;

 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.InetAddress;
 import java.util.Enumeration;
 import java.util.Hashtable;
 import java.util.TimerTask;
 import java.util.Vector;
 import java.util.logging.Logger;

 /**
  * JmDNS service information.
  *
  * @version %I%, %G%
  * @author	Arthur van Hoff, Jeff Sonstein, Werner Randelshofer
  */
 public class ServiceInfo implements DNSListener
 {
     private static Logger logger = Logger.getLogger(ServiceInfo.class.toString());
     public final static byte[] NO_VALUE = new byte[0];
     JmDNS dns;

     // State machine
     /**
      * The state of this service info.
      * This is used only for services announced by JmDNS.
      * <p/>
      * For proper handling of concurrency, this variable must be
      * changed only using methods advanceState(), revertState() and cancel().
      */
     private DNSState state = DNSState.PROBING_1;

     /**
      * Task associated to this service info.
      * Possible tasks are JmDNS.Prober, JmDNS.Announcer, JmDNS.Responder,
      * JmDNS.Canceler.
      */
     TimerTask task;

     String type;
     private String name;
     String server;
     int port;
     int weight;
     int priority;
     byte text[];
     Hashtable props;
     InetAddress addr;


     /**
      * Construct a service description for registrating with JmDNS.
      *
      * @param type fully qualified service type name, such as <code>_http._tcp.local.</code>.
      * @param name unqualified service instance name, such as <code>foobar</code>
      * @param port the local port on which the service runs
      * @param text string describing the service
      */
     public ServiceInfo(String type, String name, int port, String text)
     {
         this(type, name, port, 0, 0, text);
     }

     /**
      * Construct a service description for registrating with JmDNS.
      *
      * @param type     fully qualified service type name, such as <code>_http._tcp.local.</code>.
      * @param name     unqualified service instance name, such as <code>foobar</code>
      * @param port     the local port on which the service runs
      * @param weight   weight of the service
      * @param priority priority of the service
      * @param text     string describing the service
      */
     public ServiceInfo(String type, String name, int port, int weight, int priority, String text)
     {
         this(type, name, port, weight, priority, (byte[]) null);
         try
         {
             ByteArrayOutputStream out = new ByteArrayOutputStream(text.length());
             writeUTF(out, text);
             this.text = out.toByteArray();
         }
         catch (IOException e)
         {
             throw new RuntimeException("unexpected exception: " + e);
         }
     }

     /**
      * Construct a service description for registrating with JmDNS. The properties hashtable must
      * map property names to either Strings or byte arrays describing the property values.
      *
      * @param type     fully qualified service type name, such as <code>_http._tcp.local.</code>.
      * @param name     unqualified service instance name, such as <code>foobar</code>
      * @param port     the local port on which the service runs
      * @param weight   weight of the service
      * @param priority priority of the service
      * @param props    properties describing the service
      */
     public ServiceInfo(String type, String name, int port, int weight, int priority, Hashtable props)
     {
         this(type, name, port, weight, priority, new byte[0]);
         if (props != null)
         {
             try
             {
                 ByteArrayOutputStream out = new ByteArrayOutputStream(256);
                 for (Enumeration e = props.keys(); e.hasMoreElements();)
                 {
                     String key = (String) e.nextElement();
                     Object val = props.get(key);
                     ByteArrayOutputStream out2 = new ByteArrayOutputStream(100);
                     writeUTF(out2, key);
                     if (val instanceof String)
                     {
                         out2.write('=');
                         writeUTF(out2, (String) val);
                     }
                     else
                     {
                         if (val instanceof byte[])
                         {
                             out2.write('=');
                             byte[] bval = (byte[]) val;
                             out2.write(bval, 0, bval.length);
                         }
                         else
                         {
                             if (val != NO_VALUE)
                             {
                                 throw new IllegalArgumentException("invalid property value: " + val);
                             }
                         }
                     }
                     byte data[] = out2.toByteArray();
                     out.write(data.length);
                     out.write(data, 0, data.length);
                 }
                 this.text = out.toByteArray();
             }
             catch (IOException e)
             {
                 throw new RuntimeException("unexpected exception: " + e);
             }
         }
     }

     /**
      * Construct a service description for registrating with JmDNS.
      *
      * @param type     fully qualified service type name, such as <code>_http._tcp.local.</code>.
      * @param name     unqualified service instance name, such as <code>foobar</code>
      * @param port     the local port on which the service runs
      * @param weight   weight of the service
      * @param priority priority of the service
      * @param text     bytes describing the service
      */
     public ServiceInfo(String type, String name, int port, int weight, int priority, byte text[])
     {
         this.type = type;
         this.name = name;
         this.port = port;
         this.weight = weight;
         this.priority = priority;
         this.text = text;
     }

     /**
      * Construct a service record during service discovery.
      */
     ServiceInfo(String type, String name)
     {
         if (!type.endsWith("."))
         {
             throw new IllegalArgumentException("type must be fully qualified DNS name ending in '.': " + type);
         }

         this.type = type;
         this.name = name;
     }

     /**
      * During recovery we need to duplicate service info to reregister them
      */
     ServiceInfo(ServiceInfo info)
     {
         if (info != null)
         {
             this.type = info.type;
             this.name = info.name;
             this.port = info.port;
             this.weight = info.weight;
             this.priority = info.priority;
             this.text = info.text;
         }
     }

     /**
      * Fully qualified service type name, such as <code>_http._tcp.local.</code> .
      */
     public String getType()
     {
         return type;
     }

     /**
      * Unqualified service instance name, such as <code>foobar</code> .
      */
     public String getName()
     {
         return name;
     }

     /**
      * Sets the service instance name.
      *
      * @param name unqualified service instance name, such as <code>foobar</code>
      */
     void setName(String name)
     {
         this.name = name;
     }

     /**
      * Fully qualified service name, such as <code>foobar._http._tcp.local.</code> .
      */
     public String getQualifiedName()
     {
         return name + "." + type;
     }

     /**
      * Get the name of the server.
      */
     public String getServer()
     {
         return server;
     }

     /**
      * Get the host address of the service (ie X.X.X.X).
      */
     public String getHostAddress()
     {
         return (addr != null ? addr.getHostAddress() : "");
     }

     public InetAddress getAddress()
     {
         return addr;
     }

     /**
      * Get the InetAddress of the service.
      */
     public InetAddress getInetAddress()
     {
         return addr;
     }

     /**
      * Get the port for the service.
      */
     public int getPort()
     {
         return port;
     }

     /**
      * Get the priority of the service.
      */
     public int getPriority()
     {
         return priority;
     }

     /**
      * Get the weight of the service.
      */
     public int getWeight()
     {
         return weight;
     }

     /**
      * Get the text for the serivce as raw bytes.
      */
     public byte[] getTextBytes()
     {
         return text;
     }

     /**
      * Get the text for the service. This will interpret the text bytes
      * as a UTF8 encoded string. Will return null if the bytes are not
      * a valid UTF8 encoded string.
      */
     public String getTextString()
     {
         if ((text == null) || (text.length == 0) || ((text.length == 1) && (text[0] == 0)))
         {
             return null;
         }
         return readUTF(text, 0, text.length);
     }

     /**
      * Get the URL for this service. An http URL is created by
      * combining the address, port, and path properties.
      */
     public String getURL()
     {
         return getURL("http");
     }

     /**
      * Get the URL for this service. An URL is created by
      * combining the protocol, address, port, and path properties.
      */
     public String getURL(String protocol)
     {
         String url = protocol + "://" + getAddress() + ":" + getPort();
         String path = getPropertyString("path");
         if (path != null)
         {
             if (path.indexOf("://") >= 0)
             {
                 url = path;
             }
             else
             {
                 url += path.startsWith("/") ? path : "/" + path;
             }
         }
         return url;
     }

     /**
      * Get a property of the service. This involves decoding the
      * text bytes into a property list. Returns null if the property
      * is not found or the text data could not be decoded correctly.
      */
     public synchronized byte[] getPropertyBytes(String name)
     {
         return (byte[]) getProperties().get(name);
     }

     /**
      * Get a property of the service. This involves decoding the
      * text bytes into a property list. Returns null if the property
      * is not found, the text data could not be decoded correctly, or
      * the resulting bytes are not a valid UTF8 string.
      */
     public synchronized String getPropertyString(String name)
     {
         byte data[] = (byte[]) getProperties().get(name);
         if (data == null)
         {
             return null;
         }
         if (data == NO_VALUE)
         {
             return "true";
         }
         return readUTF(data, 0, data.length);
     }

     /**
      * Enumeration of the property names.
      */
     public Enumeration getPropertyNames()
     {
         Hashtable props = getProperties();
         return (props != null) ? props.keys() : new Vector().elements();
     }

     /**
      * Write a UTF string with a length to a stream.
      */
     void writeUTF(OutputStream out, String str) throws IOException
     {
         for (int i = 0, len = str.length(); i < len; i++)
         {
             int c = str.charAt(i);
             if ((c >= 0x0001) && (c <= 0x007F))
             {
                 out.write(c);
             }
             else
             {
                 if (c > 0x07FF)
                 {
                     out.write(0xE0 | ((c >> 12) & 0x0F));
                     out.write(0x80 | ((c >> 6) & 0x3F));
                     out.write(0x80 | ((c >> 0) & 0x3F));
                 }
                 else
                 {
                     out.write(0xC0 | ((c >> 6) & 0x1F));
                     out.write(0x80 | ((c >> 0) & 0x3F));
                 }
             }
         }
     }

     /**
      * Read data bytes as a UTF stream.
      */
     String readUTF(byte data[], int off, int len)
     {
         StringBuffer buf = new StringBuffer();
         for (int end = off + len; off < end;)
         {
             int ch = data[off++] & 0xFF;
             switch (ch >> 4)
             {
                 case 0:
                 case 1:
                 case 2:
                 case 3:
                 case 4:
                 case 5:
                 case 6:
                 case 7:
                     // 0xxxxxxx
                     break;
                 case 12:
                 case 13:
                     if (off >= len)
                     {
                         return null;
                     }
                     // 110x xxxx   10xx xxxx
                     ch = ((ch & 0x1F) << 6) | (data[off++] & 0x3F);
                     break;
                 case 14:
                     if (off + 2 >= len)
                     {
                         return null;
                     }
                     // 1110 xxxx  10xx xxxx  10xx xxxx
                     ch = ((ch & 0x0f) << 12) | ((data[off++] & 0x3F) << 6) | (data[off++] & 0x3F);
                     break;
                 default:
                     if (off + 1 >= len)
                     {
                         return null;
                     }
                     // 10xx xxxx,  1111 xxxx
                     ch = ((ch & 0x3F) << 4) | (data[off++] & 0x0f);
                     break;
             }
             buf.append((char) ch);
         }
         return buf.toString();
     }

     synchronized Hashtable getProperties()
     {
         if ((props == null) && (text != null))
         {
             Hashtable props = new Hashtable();
             int off = 0;
             while (off < text.length)
             {
                 // length of the next key value pair
                 int len = text[off++] & 0xFF;
                 if ((len == 0) || (off + len > text.length))
                 {
                     props.clear();
                     break;
                 }
                 // look for the '='
                 int i = 0;
                 for (; (i < len) && (text[off + i] != '='); i++)
                 {
                     ;
                 }

                 // get the property name
                 String name = readUTF(text, off, i);
                 if (name == null)
                 {
                     props.clear();
                     break;
                 }
                 if (i == len)
                 {
                     props.put(name, NO_VALUE);
                 }
                 else
                 {
                     byte value[] = new byte[len - ++i];
                     System.arraycopy(text, off + i, value, 0, len - i);
                     props.put(name, value);
                     off += len;
                 }
             }
             this.props = props;
         }
         return props;
     }

     // REMIND: Oops, this shouldn't be public!
     /**
      * JmDNS callback to update a DNS record.
      */
     public void updateRecord(JmDNS jmdns, long now, DNSRecord rec)
     {
         if ((rec != null) && !rec.isExpired(now))
         {
             switch (rec.type)
             {
                 case DNSConstants.TYPE_A:		// IPv4
                 case DNSConstants.TYPE_AAAA:	// IPv6 FIXME [PJYF Oct 14 2004] This has not been tested
                     if (rec.name.equals(server))
                     {
                         addr = ((DNSRecord.Address) rec).getAddress();

                     }
                     break;
                 case DNSConstants.TYPE_SRV:
                     if (rec.name.equals(getQualifiedName()))
                     {
                         DNSRecord.Service srv = (DNSRecord.Service) rec;
                         server = srv.server;
                         port = srv.port;
                         weight = srv.weight;
                         priority = srv.priority;
                         addr = null;
                         // changed to use getCache() instead - jeffs
                         // updateRecord(jmdns, now, (DNSRecord)jmdns.cache.get(server, TYPE_A, CLASS_IN));
                         updateRecord(jmdns, now, (DNSRecord) jmdns.getCache().get(server, DNSConstants.TYPE_A, DNSConstants.CLASS_IN));
                     }
                     break;
                 case DNSConstants.TYPE_TXT:
                     if (rec.name.equals(getQualifiedName()))
                     {
                         DNSRecord.Text txt = (DNSRecord.Text) rec;
                         text = txt.text;
                     }
                     break;
             }
             // Future Design Pattern
             // This is done, to notify the wait loop in method
             // JmDNS.getServiceInfo(type, name, timeout);
             if (hasData() && dns != null)
             {
                 dns.handleServiceResolved(this);
                 dns = null;
             }
             synchronized (this)
             {
                 notifyAll();
             }
         }
     }

     /**
      * Returns true if the service info is filled with data.
      */
     boolean hasData()
     {
         return server != null && addr != null && text != null;
     }


     // State machine
     /**
      * Sets the state and notifies all objects that wait on the ServiceInfo.
      */
     synchronized void advanceState()
     {
         state = state.advance();
         notifyAll();
     }

     /**
      * Sets the state and notifies all objects that wait on the ServiceInfo.
      */
     synchronized void revertState()
     {
         state = state.revert();
         notifyAll();
     }

     /**
      * Sets the state and notifies all objects that wait on the ServiceInfo.
      */
     synchronized void cancel()
     {
         state = DNSState.CANCELED;
         notifyAll();
     }

     /**
      * Returns the current state of this info.
      */
     DNSState getState()
     {
         return state;
     }


     public int hashCode()
     {
         return getQualifiedName().hashCode();
     }

     public boolean equals(Object obj)
     {
         return (obj instanceof ServiceInfo) && getQualifiedName().equals(((ServiceInfo) obj).getQualifiedName());
     }

     public String getNiceTextString()
     {
         StringBuffer buf = new StringBuffer();
         for (int i = 0, len = text.length; i < len; i++)
         {
             if (i >= 20)
             {
                 buf.append("...");
                 break;
             }
             int ch = text[i] & 0xFF;
             if ((ch < ' ') || (ch > 127))
             {
                 buf.append("\\0");
                 buf.append(Integer.toString(ch, 8));
             }
             else
             {
                 buf.append((char) ch);
             }
         }
         return buf.toString();
     }

     public String toString()
     {
         StringBuffer buf = new StringBuffer();
         buf.append("service[");
         buf.append(getQualifiedName());
         buf.append(',');
         buf.append(getAddress());
         buf.append(':');
         buf.append(port);
         buf.append(',');
         buf.append(getNiceTextString());
         buf.append(']');
         return buf.toString();
     }
 }
	/**
	* Copyright 2003-2005 Arthur van Hoff, Rick Blair
	*
	* 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.activemq.jmdns;

	import java.io.ByteArrayOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;
	import java.net.InetAddress;
	import java.util.Enumeration;
	import java.util.Hashtable;
	import java.util.TimerTask;
	import java.util.Vector;
	import java.util.logging.Logger;

	/**
	* JmDNS service information.
	*
	* @version %I%, %G%
	* @author Arthur van Hoff, Jeff Sonstein, Werner Randelshofer
	*/
	public class ServiceInfo implements DNSListener
	{
	private static Logger logger = Logger.getLogger(ServiceInfo.class.toString());
	public final static byte[] NO_VALUE = new byte[0];
	JmDNS dns;

	// State machine
	/**
	* The state of this service info.
	* This is used only for services announced by JmDNS.
	* <p/>
	* For proper handling of concurrency, this variable must be
	* changed only using methods advanceState(), revertState() and cancel().
	*/
	private DNSState state = DNSState.PROBING_1;

	/**
	* Task associated to this service info.
	* Possible tasks are JmDNS.Prober, JmDNS.Announcer, JmDNS.Responder,
	* JmDNS.Canceler.
	*/
	TimerTask task;

	String type;
	private String name;
	String server;
	int port;
	int weight;
	int priority;
	byte text[];
	Hashtable props;
	InetAddress addr;


	/**
	* Construct a service description for registrating with JmDNS.
	*
	* @param type fully qualified service type name, such as <code>_http._tcp.local.</code>.
	* @param name unqualified service instance name, such as <code>foobar</code>
	* @param port the local port on which the service runs
	* @param text string describing the service
	*/
	public ServiceInfo(String type, String name, int port, String text)
	{
	this(type, name, port, 0, 0, text);
	}

	/**
	* Construct a service description for registrating with JmDNS.
	*
	* @param type fully qualified service type name, such as <code>_http._tcp.local.</code>.
	* @param name unqualified service instance name, such as <code>foobar</code>
	* @param port the local port on which the service runs
	* @param weight weight of the service
	* @param priority priority of the service
	* @param text string describing the service
	*/
	public ServiceInfo(String type, String name, int port, int weight, int priority, String text)
	{
	this(type, name, port, weight, priority, (byte[]) null);
	try
	{
	ByteArrayOutputStream out = new ByteArrayOutputStream(text.length());
	writeUTF(out, text);
	this.text = out.toByteArray();
	}
	catch (IOException e)
	{
	throw new RuntimeException("unexpected exception: " + e);
	}
	}

	/**
	* Construct a service description for registrating with JmDNS. The properties hashtable must
	* map property names to either Strings or byte arrays describing the property values.
	*
	* @param type fully qualified service type name, such as <code>_http._tcp.local.</code>.
	* @param name unqualified service instance name, such as <code>foobar</code>
	* @param port the local port on which the service runs
	* @param weight weight of the service
	* @param priority priority of the service
	* @param props properties describing the service
	*/
	public ServiceInfo(String type, String name, int port, int weight, int priority, Hashtable props)
	{
	this(type, name, port, weight, priority, new byte[0]);
	if (props != null)
	{
	try
	{
	ByteArrayOutputStream out = new ByteArrayOutputStream(256);
	for (Enumeration e = props.keys(); e.hasMoreElements();)
	{
	String key = (String) e.nextElement();
	Object val = props.get(key);
	ByteArrayOutputStream out2 = new ByteArrayOutputStream(100);
	writeUTF(out2, key);
	if (val instanceof String)
	{
	out2.write('=');
	writeUTF(out2, (String) val);
	}
	else
	{
	if (val instanceof byte[])
	{
	out2.write('=');
	byte[] bval = (byte[]) val;
	out2.write(bval, 0, bval.length);
	}
	else
	{
	if (val != NO_VALUE)
	{
	throw new IllegalArgumentException("invalid property value: " + val);
	}
	}
	}
	byte data[] = out2.toByteArray();
	out.write(data.length);
	out.write(data, 0, data.length);
	}
	this.text = out.toByteArray();
	}
	catch (IOException e)
	{
	throw new RuntimeException("unexpected exception: " + e);
	}
	}
	}

	/**
	* Construct a service description for registrating with JmDNS.
	*
	* @param type fully qualified service type name, such as <code>_http._tcp.local.</code>.
	* @param name unqualified service instance name, such as <code>foobar</code>
	* @param port the local port on which the service runs
	* @param weight weight of the service
	* @param priority priority of the service
	* @param text bytes describing the service
	*/
	public ServiceInfo(String type, String name, int port, int weight, int priority, byte text[])
	{
	this.type = type;
	this.name = name;
	this.port = port;
	this.weight = weight;
	this.priority = priority;
	this.text = text;
	}

	/**
	* Construct a service record during service discovery.
	*/
	ServiceInfo(String type, String name)
	{
	if (!type.endsWith("."))
	{
	throw new IllegalArgumentException("type must be fully qualified DNS name ending in '.': " + type);
	}

	this.type = type;
	this.name = name;
	}

	/**
	* During recovery we need to duplicate service info to reregister them
	*/
	ServiceInfo(ServiceInfo info)
	{
	if (info != null)
	{
	this.type = info.type;
	this.name = info.name;
	this.port = info.port;
	this.weight = info.weight;
	this.priority = info.priority;
	this.text = info.text;
	}
	}

	/**
	* Fully qualified service type name, such as <code>_http._tcp.local.</code> .
	*/
	public String getType()
	{
	return type;
	}

	/**
	* Unqualified service instance name, such as <code>foobar</code> .
	*/
	public String getName()
	{
	return name;
	}

	/**
	* Sets the service instance name.
	*
	* @param name unqualified service instance name, such as <code>foobar</code>
	*/
	void setName(String name)
	{
	this.name = name;
	}

	/**
	* Fully qualified service name, such as <code>foobar._http._tcp.local.</code> .
	*/
	public String getQualifiedName()
	{
	return name + "." + type;
	}

	/**
	* Get the name of the server.
	*/
	public String getServer()
	{
	return server;
	}

	/**
	* Get the host address of the service (ie X.X.X.X).
	*/
	public String getHostAddress()
	{
	return (addr != null ? addr.getHostAddress() : "");
	}

	public InetAddress getAddress()
	{
	return addr;
	}

	/**
	* Get the InetAddress of the service.
	*/
	public InetAddress getInetAddress()
	{
	return addr;
	}

	/**
	* Get the port for the service.
	*/
	public int getPort()
	{
	return port;
	}

	/**
	* Get the priority of the service.
	*/
	public int getPriority()
	{
	return priority;
	}

	/**
	* Get the weight of the service.
	*/
	public int getWeight()
	{
	return weight;
	}

	/**
	* Get the text for the serivce as raw bytes.
	*/
	public byte[] getTextBytes()
	{
	return text;
	}

	/**
	* Get the text for the service. This will interpret the text bytes
	* as a UTF8 encoded string. Will return null if the bytes are not
	* a valid UTF8 encoded string.
	*/
	public String getTextString()
	{
	if ((text == null) \|\| (text.length == 0) \|\| ((text.length == 1) && (text[0] == 0)))
	{
	return null;
	}
	return readUTF(text, 0, text.length);
	}

	/**
	* Get the URL for this service. An http URL is created by
	* combining the address, port, and path properties.
	*/
	public String getURL()
	{
	return getURL("http");
	}

	/**
	* Get the URL for this service. An URL is created by
	* combining the protocol, address, port, and path properties.
	*/
	public String getURL(String protocol)
	{
	String url = protocol + "://" + getAddress() + ":" + getPort();
	String path = getPropertyString("path");
	if (path != null)
	{
	if (path.indexOf("://") >= 0)
	{
	url = path;
	}
	else
	{
	url += path.startsWith("/") ? path : "/" + path;
	}
	}
	return url;
	}

	/**
	* Get a property of the service. This involves decoding the
	* text bytes into a property list. Returns null if the property
	* is not found or the text data could not be decoded correctly.
	*/
	public synchronized byte[] getPropertyBytes(String name)
	{
	return (byte[]) getProperties().get(name);
	}

	/**
	* Get a property of the service. This involves decoding the
	* text bytes into a property list. Returns null if the property
	* is not found, the text data could not be decoded correctly, or
	* the resulting bytes are not a valid UTF8 string.
	*/
	public synchronized String getPropertyString(String name)
	{
	byte data[] = (byte[]) getProperties().get(name);
	if (data == null)
	{
	return null;
	}
	if (data == NO_VALUE)
	{
	return "true";
	}
	return readUTF(data, 0, data.length);
	}

	/**
	* Enumeration of the property names.
	*/
	public Enumeration getPropertyNames()
	{
	Hashtable props = getProperties();
	return (props != null) ? props.keys() : new Vector().elements();
	}

	/**
	* Write a UTF string with a length to a stream.
	*/
	void writeUTF(OutputStream out, String str) throws IOException
	{
	for (int i = 0, len = str.length(); i < len; i++)
	{
	int c = str.charAt(i);
	if ((c >= 0x0001) && (c <= 0x007F))
	{
	out.write(c);
	}
	else
	{
	if (c > 0x07FF)
	{
	out.write(0xE0 \| ((c >> 12) & 0x0F));
	out.write(0x80 \| ((c >> 6) & 0x3F));
	out.write(0x80 \| ((c >> 0) & 0x3F));
	}
	else
	{
	out.write(0xC0 \| ((c >> 6) & 0x1F));
	out.write(0x80 \| ((c >> 0) & 0x3F));
	}
	}
	}
	}

	/**
	* Read data bytes as a UTF stream.
	*/
	String readUTF(byte data[], int off, int len)
	{
	StringBuffer buf = new StringBuffer();
	for (int end = off + len; off < end;)
	{
	int ch = data[off++] & 0xFF;
	switch (ch >> 4)
	{
	case 0:
	case 1:
	case 2:
	case 3:
	case 4:
	case 5:
	case 6:
	case 7:
	// 0xxxxxxx
	break;
	case 12:
	case 13:
	if (off >= len)
	{
	return null;
	}
	// 110x xxxx 10xx xxxx
	ch = ((ch & 0x1F) << 6) \| (data[off++] & 0x3F);
	break;
	case 14:
	if (off + 2 >= len)
	{
	return null;
	}
	// 1110 xxxx 10xx xxxx 10xx xxxx
	ch = ((ch & 0x0f) << 12) \| ((data[off++] & 0x3F) << 6) \| (data[off++] & 0x3F);
	break;
	default:
	if (off + 1 >= len)
	{
	return null;
	}
	// 10xx xxxx, 1111 xxxx
	ch = ((ch & 0x3F) << 4) \| (data[off++] & 0x0f);
	break;
	}
	buf.append((char) ch);
	}
	return buf.toString();
	}

	synchronized Hashtable getProperties()
	{
	if ((props == null) && (text != null))
	{
	Hashtable props = new Hashtable();
	int off = 0;
	while (off < text.length)
	{
	// length of the next key value pair
	int len = text[off++] & 0xFF;
	if ((len == 0) \|\| (off + len > text.length))
	{
	props.clear();
	break;
	}
	// look for the '='
	int i = 0;
	for (; (i < len) && (text[off + i] != '='); i++)
	{
	;
	}

	// get the property name
	String name = readUTF(text, off, i);
	if (name == null)
	{
	props.clear();
	break;
	}
	if (i == len)
	{
	props.put(name, NO_VALUE);
	}
	else
	{
	byte value[] = new byte[len - ++i];
	System.arraycopy(text, off + i, value, 0, len - i);
	props.put(name, value);
	off += len;
	}
	}
	this.props = props;
	}
	return props;
	}

	// REMIND: Oops, this shouldn't be public!
	/**
	* JmDNS callback to update a DNS record.
	*/
	public void updateRecord(JmDNS jmdns, long now, DNSRecord rec)
	{
	if ((rec != null) && !rec.isExpired(now))
	{
	switch (rec.type)
	{
	case DNSConstants.TYPE_A: // IPv4
	case DNSConstants.TYPE_AAAA: // IPv6 FIXME [PJYF Oct 14 2004] This has not been tested
	if (rec.name.equals(server))
	{
	addr = ((DNSRecord.Address) rec).getAddress();

	}
	break;
	case DNSConstants.TYPE_SRV:
	if (rec.name.equals(getQualifiedName()))
	{
	DNSRecord.Service srv = (DNSRecord.Service) rec;
	server = srv.server;
	port = srv.port;
	weight = srv.weight;
	priority = srv.priority;
	addr = null;
	// changed to use getCache() instead - jeffs
	// updateRecord(jmdns, now, (DNSRecord)jmdns.cache.get(server, TYPE_A, CLASS_IN));
	updateRecord(jmdns, now, (DNSRecord) jmdns.getCache().get(server, DNSConstants.TYPE_A, DNSConstants.CLASS_IN));
	}
	break;
	case DNSConstants.TYPE_TXT:
	if (rec.name.equals(getQualifiedName()))
	{
	DNSRecord.Text txt = (DNSRecord.Text) rec;
	text = txt.text;
	}
	break;
	}
	// Future Design Pattern
	// This is done, to notify the wait loop in method
	// JmDNS.getServiceInfo(type, name, timeout);
	if (hasData() && dns != null)
	{
	dns.handleServiceResolved(this);
	dns = null;
	}
	synchronized (this)
	{
	notifyAll();
	}
	}
	}

	/**
	* Returns true if the service info is filled with data.
	*/
	boolean hasData()
	{
	return server != null && addr != null && text != null;
	}


	// State machine
	/**
	* Sets the state and notifies all objects that wait on the ServiceInfo.
	*/
	synchronized void advanceState()
	{
	state = state.advance();
	notifyAll();
	}

	/**
	* Sets the state and notifies all objects that wait on the ServiceInfo.
	*/
	synchronized void revertState()
	{
	state = state.revert();
	notifyAll();
	}

	/**
	* Sets the state and notifies all objects that wait on the ServiceInfo.
	*/
	synchronized void cancel()
	{
	state = DNSState.CANCELED;
	notifyAll();
	}

	/**
	* Returns the current state of this info.
	*/
	DNSState getState()
	{
	return state;
	}


	public int hashCode()
	{
	return getQualifiedName().hashCode();
	}

	public boolean equals(Object obj)
	{
	return (obj instanceof ServiceInfo) && getQualifiedName().equals(((ServiceInfo) obj).getQualifiedName());
	}

	public String getNiceTextString()
	{
	StringBuffer buf = new StringBuffer();
	for (int i = 0, len = text.length; i < len; i++)
	{
	if (i >= 20)
	{
	buf.append("...");
	break;
	}
	int ch = text[i] & 0xFF;
	if ((ch < ' ') \|\| (ch > 127))
	{
	buf.append("\\0");
	buf.append(Integer.toString(ch, 8));
	}
	else
	{
	buf.append((char) ch);
	}
	}
	return buf.toString();
	}

	public String toString()
	{
	StringBuffer buf = new StringBuffer();
	buf.append("service[");
	buf.append(getQualifiedName());
	buf.append(',');
	buf.append(getAddress());
	buf.append(':');
	buf.append(port);
	buf.append(',');
	buf.append(getNiceTextString());
	buf.append(']');
	return buf.toString();
	}
	}