2003-11-26 Michael Koch <konqueror@gmx.de>

	* java/net/DatagramSocket.java
	(impl): Made private.
	(bound): New private member variable.
	(DatagramSocket): Fixed documentation, use getImpl().
	(getImpl): New package-private method.
	(isClosed): Use getImpl().
	(getLocalAddress): Completed documentation, use getImpl().
	(getLocalPort): Use getImpl().
	(getSoTimeout): Likewise.
	(setSoTimeout): Likewise.
	(getSendBufferSize): Likewise.
	(setSendBufferSize): Likewise.
	(getReceiveBufferSize): Likewise.
	(setReceiveBufferSize): Likewise.
	(connect): Likewise.
	(disconnect): Likewise.
	(receive): Likewise.
	(send): Likewise.
	(setReuseAddress): Likewise.
	(setTrafficClass): Likewise.
	(bind): Added message to exception.
	(isClosed): Completed documentation.
	(getChannel): Likewise.
	(connect): Added missing exception, refined exception message.
	(isBound): Completed documentation, just return bound.
	(isConnected): Completed documentation.
	(getRemoteSocketAddress): Likewise.
	(getReuseAddress): Completed documentation, use getImpl().
	(setSoBroadcast): Likewise.
	(getSoBroadcast): Likewise.
	(getTrafficClass): Likewise.
	(getLocalSocketAddress): Simplified.
	* java/net/MulticastSocket.java
	(MulticastSocket): Removed comment not applying anymore.
	(getInterface): Use getImpl().
	(getTTL): Likewise.
	(getTimeToLive): Likewise.
	(setInterface): Likewise.
	(setNetworkInterface): Likewise.
	(getNetworkInterface): Likewise.
	(setLoopback): Likewise.
	(getLoopback): Likewise.
	(setTTL): Likewise.
	(setTimeToLive): Likewise.
	(joinGroup): Likewise.
	(leaveGroup): Likewise.
	(send): Likewise.

From-SVN: r73951

libjava/ChangeLog

 2003-11-26  Michael Koch  <konqueror@gmx.de>
 
+	* java/net/DatagramSocket.java
+	(impl): Made private.
+	(bound): New private member variable.
+	(DatagramSocket): Fixed documentation, use getImpl().
+	(getImpl): New package-private method.
+	(isClosed): Use getImpl().
+	(getLocalAddress): Completed documentation, use getImpl().
+	(getLocalPort): Use getImpl().
+	(getSoTimeout): Likewise.
+	(setSoTimeout): Likewise.
+	(getSendBufferSize): Likewise.
+	(setSendBufferSize): Likewise.
+	(getReceiveBufferSize): Likewise.
+	(setReceiveBufferSize): Likewise.
+	(connect): Likewise.
+	(disconnect): Likewise.
+	(receive): Likewise.
+	(send): Likewise.
+	(setReuseAddress): Likewise.
+	(setTrafficClass): Likewise.
+	(bind): Added message to exception.
+	(isClosed): Completed documentation.
+	(getChannel): Likewise.
+	(connect): Added missing exception, refined exception message.
+	(isBound): Completed documentation, just return bound.
+	(isConnected): Completed documentation.
+	(getRemoteSocketAddress): Likewise.
+	(getReuseAddress): Completed documentation, use getImpl().
+	(setSoBroadcast): Likewise.
+	(getSoBroadcast): Likewise.
+	(getTrafficClass): Likewise.
+	(getLocalSocketAddress): Simplified.
+	* java/net/MulticastSocket.java
+	(MulticastSocket): Removed comment not applying anymore.
+	(getInterface): Use getImpl().
+	(getTTL): Likewise.
+	(getTimeToLive): Likewise.
+	(setInterface): Likewise.
+	(setNetworkInterface): Likewise.
+	(getNetworkInterface): Likewise.
+	(setLoopback): Likewise.
+	(getLoopback): Likewise.
+	(setTTL): Likewise.
+	(setTimeToLive): Likewise.
+	(joinGroup): Likewise.
+	(leaveGroup): Likewise.
+	(send): Likewise.
+
+2003-11-26  Michael Koch  <konqueror@gmx.de>
+
 	* java/net/Socket.java
 	(implCreated): Dont set default value explicitely, added
 	documentation.

libjava/java/net/DatagramSocket.java

@@ -72,7 +72,12 @@ public class DatagramSocket
   /**
    * This is the implementation object used by this socket.
    */
-  DatagramSocketImpl impl;
+  private DatagramSocketImpl impl;
+
+  /**
+   * True if socket implementation was created.
+   */
+  private boolean implCreated;
 
   /**
    * This is the address we are "connected" to
@@ -85,6 +90,11 @@ public class DatagramSocket
   private int remotePort = -1;
 
   /**
+   * True if socket is bound.
+   */
+  private boolean bound;
+
+  /**
    * Creates a <code>DatagramSocket</code> from a specified 
    * <code>DatagramSocketImpl</code> instance
    *
@@ -151,8 +161,7 @@ public class DatagramSocket
    * Initializes a new instance of <code>DatagramSocket</code> that binds to 
    * the specified local port and address.
    *
-   * @param port The local port number to bind to.
-   * @param laddr The local address to bind to.
+   * @param address The local address and port number to bind to.
    *
    * @exception SecurityException If a security manager exists and its
    * <code>checkListen</code> method doesn't allow the operation.
@@ -177,7 +186,6 @@ public class DatagramSocket
 	    propVal + "DatagramSocketImpl");
 	  impl = new PlainDatagramSocketImpl();
 	}
-    impl.create();
 
     if (address == null)
       return;
@@ -200,25 +208,45 @@ public class DatagramSocket
     
     try
       {
-        impl.bind(port, addr);
+        getImpl().bind(port, addr);
       }
     catch (SocketException exception)
       {
-        impl.close();
+        getImpl().close();
         throw exception;
       }
     catch (RuntimeException exception)
       {
-        impl.close();
+        getImpl().close();
         throw exception;
       }
     catch (Error error)
       {
-        impl.close();
+        getImpl().close();
         throw error;
       }
   }
   
+  // This needs to be accessible from java.net.MulticastSocket
+  DatagramSocketImpl getImpl()
+    throws SocketException
+  {
+    try
+      {
+	if (!implCreated)
+	  {
+	    impl.create();
+	    implCreated = true;
+	  }
+
+	return impl;
+      }
+    catch (IOException e)
+      {
+	throw new SocketException(e.getMessage());
+      }
+  }
+  
   /**
    * Closes this datagram socket.
    */
@@ -226,10 +254,20 @@ public class DatagramSocket
   {
     if (!isClosed())
       {
-        impl.close();
-        impl = null;
+	try
+	  {
+	    getImpl().close();
+	  }
+	catch (SocketException e)
+	  {
+	    // Ignore this case, just close the socket in finally clause.
+	  }
+	finally
+	  {
 	    remoteAddress = null;
 	    remotePort = -1;
+	    impl = null;
+	  }
       }
   }
 
@@ -264,6 +302,8 @@ public class DatagramSocket
   /**
    * Returns the local address this datagram socket is bound to.
    * 
+   * @return The local address is the socket is bound or null
+   *
    * @since 1.1
    */
   public InetAddress getLocalAddress()
@@ -275,7 +315,7 @@ public class DatagramSocket
     
     try
       {
-	localAddr = (InetAddress) impl.getOption (SocketOptions.SO_BINDADDR);
+	localAddr = (InetAddress) getImpl().getOption(SocketOptions.SO_BINDADDR);
 
 	SecurityManager s = System.getSecurityManager();
 	if (s != null)
@@ -287,6 +327,7 @@ public class DatagramSocket
       }
     catch (SocketException e)
       {
+	// This cannot happen as we are bound.
         return null;
       }
 
@@ -303,7 +344,15 @@ public class DatagramSocket
     if (isClosed())
       return -1;
 	      
-    return impl.getLocalPort();
+    try
+      {
+	return getImpl().getLocalPort();
+      }
+    catch (SocketException e)
+      {
+	// This cannot happen as we are bound.
+	return 0;
+      }
   }
 
   /**
@@ -321,12 +370,12 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    Object timeout = impl.getOption(SocketOptions.SO_TIMEOUT);
+    Object buf = getImpl().getOption(SocketOptions.SO_TIMEOUT);
 
-    if (timeout instanceof Integer) 
-      return ((Integer)timeout).intValue();
-    else
-      return 0;
+    if (buf instanceof Integer) 
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
   }
 
   /**
@@ -348,7 +397,7 @@ public class DatagramSocket
     if (timeout < 0)
       throw new IllegalArgumentException("Invalid timeout: " + timeout);
 
-    impl.setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
+    getImpl().setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
   }
 
   /**
@@ -367,12 +416,12 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
     
-    Object obj = impl.getOption(SocketOptions.SO_SNDBUF);
+    Object buf = getImpl().getOption(SocketOptions.SO_SNDBUF);
 
-    if (obj instanceof Integer)
-      return(((Integer)obj).intValue());
-    else
-      throw new SocketException("Unexpected type");
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
   }
 
   /**
@@ -395,7 +444,7 @@ public class DatagramSocket
     if (size < 0)
       throw new IllegalArgumentException("Buffer size is less than 0");
   
-    impl.setOption(SocketOptions.SO_SNDBUF, new Integer(size));
+    getImpl().setOption(SocketOptions.SO_SNDBUF, new Integer(size));
   }
 
   /**
@@ -414,12 +463,12 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    Object obj = impl.getOption(SocketOptions.SO_RCVBUF);
+    Object buf = getImpl().getOption(SocketOptions.SO_RCVBUF);
   
-    if (obj instanceof Integer)
-      return(((Integer)obj).intValue());
-    else 
-      throw new SocketException("Unexpected type");
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
   }
 
   /**
@@ -442,7 +491,7 @@ public class DatagramSocket
     if (size < 0)
       throw new IllegalArgumentException("Buffer size is less than 0");
 
-    impl.setOption(SocketOptions.SO_RCVBUF, new Integer(size));
+    getImpl().setOption(SocketOptions.SO_RCVBUF, new Integer(size));
   }
 
   /**
@@ -475,7 +524,7 @@ public class DatagramSocket
 
     try
       {
-        impl.connect (address, port);
+        getImpl().connect (address, port);
         remoteAddress = address;
         remotePort = port;
       }
@@ -494,10 +543,23 @@ public class DatagramSocket
    */
   public void disconnect()
   {
-    impl.disconnect();
+    if (!isConnected())
+      return;
+
+    try
+      {
+	getImpl().disconnect();
+      }
+    catch (SocketException e)
+      {
+	// This cannot happen as we are connected.
+      }
+    finally
+      {
 	remoteAddress = null;
 	remotePort = -1;
       }
+  }
 
   /**
    * Reads a datagram packet from the socket.  Note that this method
@@ -532,7 +594,7 @@ public class DatagramSocket
         && !getChannel().isBlocking ())
       throw new IllegalBlockingModeException ();
 
-    impl.receive(p);
+    getImpl().receive(p);
 
     SecurityManager s = System.getSecurityManager();
     if (s != null && isConnected ())
@@ -585,7 +647,7 @@ public class DatagramSocket
         && !getChannel().isBlocking ())
       throw new IllegalBlockingModeException ();
 
-    impl.send(p);
+    getImpl().send(p);
   }
 
   /**
@@ -607,7 +669,7 @@ public class DatagramSocket
       throw new SocketException("socket is closed");
     
     if (! (address instanceof InetSocketAddress))
-      throw new IllegalArgumentException ();
+      throw new IllegalArgumentException("unsupported address type");
 
     InetSocketAddress tmp = (InetSocketAddress) address;
 
@@ -615,12 +677,15 @@ public class DatagramSocket
     if (s != null)
       s.checkListen(tmp.getPort ());
 
-    impl.bind (tmp.getPort (), tmp.getAddress ());
+    getImpl().bind (tmp.getPort (), tmp.getAddress ());
+    bound = true;
   }
 
   /**
    * Checks if the datagram socket is closed.
    *
+   * @return True if socket is closed, false otherwise.
+   * 
    * @since 1.4
    */
   public boolean isClosed()
@@ -631,6 +696,8 @@ public class DatagramSocket
   /**
    * Returns the datagram channel assoziated with this datagram socket.
    * 
+   * @return The associated <code>DatagramChannel</code> object or null
+   * 
    * @since 1.4
    */
   public DatagramChannel getChannel()
@@ -651,37 +718,32 @@ public class DatagramSocket
   public void connect (SocketAddress address) throws SocketException
   {
     if (isClosed())
+      throw new SocketException("socket is closed");
     
     if ( !(address instanceof InetSocketAddress) )
-      throw new IllegalArgumentException (
-		      "SocketAddress is not InetSocketAddress");
+      throw new IllegalArgumentException("unsupported address type");
 
     InetSocketAddress tmp = (InetSocketAddress) address;
-    connect( tmp.getAddress(), tmp.getPort());
+    connect(tmp.getAddress(), tmp.getPort());
   }
   
   /**
    * Returns the binding state of the socket.
    * 
+   * @return True if socket bound, false otherwise.
+   * 
    * @since 1.4
    */
   public boolean isBound()
   {
-    try
-      {
-        Object bindaddr = impl.getOption (SocketOptions.SO_BINDADDR);
-      }
-    catch (SocketException e)
-      {
-        return false;
-      }
-
-    return true;
+    return bound;
   }
 
   /**
    * Returns the connection state of the socket.
    * 
+   * @return True if socket is connected, false otherwise.
+   * 
    * @since 1.4
    */
   public boolean isConnected()
@@ -693,6 +755,8 @@ public class DatagramSocket
    * Returns the SocketAddress of the host this socket is conneted to
    * or null if this socket is not connected.
    * 
+   * @return The socket address of the remote host if connected or null
+   * 
    * @since 1.4
    */
   public SocketAddress getRemoteSocketAddress()
@@ -704,25 +768,18 @@ public class DatagramSocket
   }
 
   /**
-   * Returns the local SocketAddress this socket is bound to
-   * or null if it is not bound.
+   * Returns the local SocketAddress this socket is bound to.
+   *
+   * @return The local SocketAddress or null if the socket is not bound.
    * 
    * @since 1.4
    */
   public SocketAddress getLocalSocketAddress()
   {
-    InetAddress addr;
-    
-    try
-      {
-        addr = (InetAddress) impl.getOption (SocketOptions.SO_BINDADDR);
-      }
-    catch (SocketException e)
-      {
+    if (!isBound())
       return null;
-      }
     
-    return new InetSocketAddress (addr, impl.localPort);
+    return new InetSocketAddress (getLocalAddress(), getLocalPort());
   }
 
   /**
@@ -739,12 +796,14 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    impl.setOption (SocketOptions.SO_REUSEADDR, new Boolean (on));
+    getImpl().setOption (SocketOptions.SO_REUSEADDR, new Boolean (on));
   }
 
   /**
    * Checks if SO_REUSEADDR is enabled.
    *
+   * @return True if SO_REUSEADDR is set on the socket, false otherwise.
+   *
    * @exception SocketException If an error occurs.
    * 
    * @since 1.4
@@ -754,34 +813,36 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    Object obj = impl.getOption (SocketOptions.SO_REUSEADDR);
+    Object buf = getImpl().getOption (SocketOptions.SO_REUSEADDR);
   
-    if (obj instanceof Boolean)
-      return(((Boolean) obj).booleanValue ());
-    else 
-      throw new SocketException ("Unexpected type");
+    if (buf instanceof Boolean)
+      return ((Boolean) buf).booleanValue();
+
+    throw new SocketException("unexpected type");
   }
 
   /**
    * Enables/Disables SO_BROADCAST
    * 
-   * @param on Whether or not to have SO_BROADCAST turned on
+   * @param enable True if SO_BROADCAST should be enabled, false otherwise.
    *
    * @exception SocketException If an error occurs
    *
    * @since 1.4
    */
-  public void setBroadcast(boolean on) throws SocketException
+  public void setBroadcast(boolean enable) throws SocketException
   {
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    impl.setOption (SocketOptions.SO_BROADCAST, new Boolean (on));
+    getImpl().setOption(SocketOptions.SO_BROADCAST, new Boolean(enable));
   }
 
   /**
    * Checks if SO_BROADCAST is enabled
    * 
+   * @return Whether SO_BROADCAST is set
+   *
    * @exception SocketException If an error occurs
    * 
    * @since 1.4
@@ -791,12 +852,12 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    Object obj = impl.getOption (SocketOptions.SO_BROADCAST);
+    Object buf = getImpl().getOption(SocketOptions.SO_BROADCAST);
   
-    if (obj instanceof Boolean)
-      return ((Boolean) obj).booleanValue ();
-    else 
-      throw new SocketException ("Unexpected type");
+    if (buf instanceof Boolean)
+      return ((Boolean) buf).booleanValue();
+
+    throw new SocketException("unexpected type");
   }
 
   /**
@@ -820,12 +881,14 @@ public class DatagramSocket
     if (tc < 0 || tc > 255)
       throw new IllegalArgumentException();
 
-    impl.setOption (SocketOptions.IP_TOS, new Integer (tc));
+    getImpl().setOption (SocketOptions.IP_TOS, new Integer (tc));
   }
   
   /**
    * Returns the current traffic class
    * 
+   * @return The current traffic class.
+   *
    * @see DatagramSocket#setTrafficClass(int tc)
    *
    * @exception SocketException If an error occurs
@@ -837,12 +900,12 @@ public class DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
     
-    Object obj = impl.getOption(SocketOptions.IP_TOS);
+    Object buf = getImpl().getOption(SocketOptions.IP_TOS);
 
-    if (obj instanceof Integer)
-      return ((Integer) obj).intValue ();
-    else
-      throw new SocketException ("Unexpected type");
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
   }
   
   /**

libjava/java/net/MulticastSocket.java

@@ -67,10 +67,6 @@ import java.util.Enumeration;
  */
 public class MulticastSocket extends DatagramSocket
 {
-  // FIXME: the local addr bound to the multicast socket can be reused;
-  // unlike unicast sockets.  It binds to any available network interface.
-  // See p.1159 JCL book.
-
   /**
    * Create a MulticastSocket that this not bound to any address
    *
@@ -128,7 +124,7 @@ public class MulticastSocket extends DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    return (InetAddress) impl.getOption(SocketOptions.IP_MULTICAST_IF);
+    return (InetAddress) getImpl().getOption(SocketOptions.IP_MULTICAST_IF);
   }
 
   /**
@@ -152,7 +148,7 @@ public class MulticastSocket extends DatagramSocket
     // Use getTTL here rather than getTimeToLive in case we're using an impl
     // other than the default PlainDatagramSocketImpl and it doesn't have
     // getTimeToLive yet.
-    return impl.getTTL();
+    return getImpl().getTTL();
   }
 
   /**
@@ -170,7 +166,7 @@ public class MulticastSocket extends DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    return impl.getTimeToLive();
+    return getImpl().getTimeToLive();
   }
 
   /**
@@ -187,7 +183,7 @@ public class MulticastSocket extends DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    impl.setOption(SocketOptions.IP_MULTICAST_IF, addr);
+    getImpl().setOption(SocketOptions.IP_MULTICAST_IF, addr);
   }
 
   /**
@@ -210,10 +206,10 @@ public class MulticastSocket extends DatagramSocket
     Enumeration e = netIf.getInetAddresses ();
 
     if (!e.hasMoreElements ())
-      throw new SocketException ("MulticastSocket: Error");
+      throw new SocketException("no network devices found");
 
     InetAddress address = (InetAddress) e.nextElement ();
-    impl.setOption (SocketOptions.IP_MULTICAST_IF, address);
+    getImpl().setOption (SocketOptions.IP_MULTICAST_IF, address);
   }
 
   /**
@@ -234,7 +230,7 @@ public class MulticastSocket extends DatagramSocket
       throw new SocketException("socket is closed");
 
     InetAddress address =
-	    (InetAddress) impl.getOption (SocketOptions.IP_MULTICAST_IF);
+      (InetAddress) getImpl().getOption (SocketOptions.IP_MULTICAST_IF);
     NetworkInterface netIf = NetworkInterface.getByInetAddress (address);
 
     return netIf;
@@ -259,7 +255,7 @@ public class MulticastSocket extends DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    impl.setOption (SocketOptions.IP_MULTICAST_LOOP, new Boolean (disable));
+    getImpl().setOption (SocketOptions.IP_MULTICAST_LOOP, new Boolean (disable));
   }
 
   /**
@@ -274,12 +270,12 @@ public class MulticastSocket extends DatagramSocket
     if (isClosed())
       throw new SocketException("socket is closed");
 
-    Object obj = impl.getOption (SocketOptions.IP_MULTICAST_LOOP);
+    Object buf = getImpl().getOption (SocketOptions.IP_MULTICAST_LOOP);
 
-    if (obj instanceof Boolean)
-      return ((Boolean) obj).booleanValue ();
-    else
-      throw new SocketException ("Unexpected type");
+    if (buf instanceof Boolean)
+      return ((Boolean) buf).booleanValue();
+    
+    throw new SocketException("unexpected type");
   }
 
   /**
@@ -302,7 +298,7 @@ public class MulticastSocket extends DatagramSocket
     // Use setTTL here rather than setTimeToLive in case we're using an impl
     // other than the default PlainDatagramSocketImpl and it doesn't have
     // setTimeToLive yet.
-    impl.setTTL(ttl);
+    getImpl().setTTL(ttl);
   }
 
   /**
@@ -323,7 +319,7 @@ public class MulticastSocket extends DatagramSocket
     if (ttl <= 0 || ttl > 255)
       throw new IllegalArgumentException("Invalid ttl: " + ttl);
 
-    impl.setTimeToLive(ttl);
+    getImpl().setTimeToLive(ttl);
   }
 
   /**
@@ -347,7 +343,7 @@ public class MulticastSocket extends DatagramSocket
     if (s != null)
       s.checkMulticast(mcastaddr);
 
-    impl.join(mcastaddr);
+    getImpl().join(mcastaddr);
   }
 
   /**
@@ -371,7 +367,7 @@ public class MulticastSocket extends DatagramSocket
     if (s != null)
       s.checkMulticast(mcastaddr);
 
-    impl.leave(mcastaddr);
+    getImpl().leave(mcastaddr);
   }
 
   /**
@@ -410,7 +406,7 @@ public class MulticastSocket extends DatagramSocket
     if (s != null)
       s.checkMulticast (tmp.getAddress ());
 
-    impl.joinGroup (mcastaddr, netIf);
+    getImpl().joinGroup (mcastaddr, netIf);
   }
   
   /**
@@ -445,7 +441,7 @@ public class MulticastSocket extends DatagramSocket
     if (s != null)
       s.checkMulticast (tmp.getAddress ());
 
-    impl.leaveGroup (mcastaddr, netIf);
+    getImpl().leaveGroup (mcastaddr, netIf);
   }
   
   /**
@@ -479,9 +475,9 @@ public class MulticastSocket extends DatagramSocket
           s.checkConnect(addr.getHostAddress(), p.getPort());
       }
 
-    int oldttl = impl.getTimeToLive();
-    impl.setTimeToLive(((int) ttl) & 0xFF);
-    impl.send(p);
-    impl.setTimeToLive(oldttl);
+    int oldttl = getImpl().getTimeToLive();
+    getImpl().setTimeToLive(((int) ttl) & 0xFF);
+    getImpl().send(p);
+    getImpl().setTimeToLive(oldttl);
   }
 } // class MulticastSocket