Merged gcj-eclipse branch to trunk.

From-SVN: r120621

1 files changed, 939 insertions, 0 deletions

diff --git a/libjava/java/net/DatagramSocket.java b/libjava/java/net/DatagramSocket.java
new file mode 100644
index 00000000000..d8837c006b5
--- /dev/null
+++ b/libjava/java/net/DatagramSocket.java
@@ -0,0 +1,939 @@
+/* DatagramSocket.java -- A class to model UDP sockets
+   Copyright (C) 1998, 1999, 2000, 2002, 2003, 2004, 2005
+   Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package java.net;
+
+import gnu.classpath.SystemProperties;
+
+import gnu.java.net.PlainDatagramSocketImpl;
+import gnu.java.nio.DatagramChannelImpl;
+
+import java.io.IOException;
+import java.nio.channels.DatagramChannel;
+import java.nio.channels.IllegalBlockingModeException;
+
+
+/**
+ * Written using on-line Java Platform 1.2 API Specification, as well
+ * as "The Java Class Libraries", 2nd edition (Addison-Wesley, 1998).
+ * Status:  Believed complete and correct.
+ */
+/**
+ * This class models a connectionless datagram socket that sends
+ * individual packets of data across the network.  In the TCP/IP world,
+ * this means UDP.  Datagram packets do not have guaranteed delivery,
+ * or any guarantee about the order the data will be received on the
+ * remote host.
+ *
+ * @author Aaron M. Renn (arenn@urbanophile.com)
+ * @author Warren Levy (warrenl@cygnus.com)
+ * @date May 3, 1999.
+ */
+public class DatagramSocket
+{
+  /**
+   * This is the user DatagramSocketImplFactory for this class.  If this
+   * variable is null, a default factory is used.
+   */
+  private static DatagramSocketImplFactory factory;
+
+  /**
+   * This is the implementation object used by this socket.
+   */
+  private DatagramSocketImpl impl;
+
+  /**
+   * True if socket implementation was created.
+   */
+  private boolean implCreated;
+
+  /**
+   * This is the address we are "connected" to
+   */
+  private InetAddress remoteAddress;
+
+  /**
+   * This is the port we are "connected" to
+   */
+  private int remotePort = -1;
+
+  /**
+   * True if socket is bound.
+   */
+  private boolean bound;
+
+  /**
+   * Creates a <code>DatagramSocket</code> from a specified
+   * <code>DatagramSocketImpl</code> instance
+   *
+   * @param impl The <code>DatagramSocketImpl</code> the socket will be
+   * created from
+   *
+   * @since 1.4
+   */
+  protected DatagramSocket(DatagramSocketImpl impl)
+  {
+    if (impl == null)
+      throw new NullPointerException("impl may not be null");
+
+    this.impl = impl;
+    this.remoteAddress = null;
+    this.remotePort = -1;
+  }
+
+  /**
+   * Initializes a new instance of <code>DatagramSocket</code> that binds to
+   * a random port and every address on the local machine.
+   *
+   * @exception SocketException If an error occurs.
+   * @exception SecurityException If a security manager exists and
+   * its <code>checkListen</code> method doesn't allow the operation.
+   */
+  public DatagramSocket() throws SocketException
+  {
+    this(new InetSocketAddress(0));
+  }
+
+  /**
+   * Initializes a new instance of <code>DatagramSocket</code> that binds to
+   * the specified port and every address on the local machine.
+   *
+   * @param port The local port number to bind to.
+   *
+   * @exception SecurityException If a security manager exists and its
+   * <code>checkListen</code> method doesn't allow the operation.
+   * @exception SocketException If an error occurs.
+   */
+  public DatagramSocket(int port) throws SocketException
+  {
+    this(new InetSocketAddress(port));
+  }
+
+  /**
+   * 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 addr The local address to bind to.
+   *
+   * @exception SecurityException If a security manager exists and its
+   * checkListen method doesn't allow the operation.
+   * @exception SocketException If an error occurs.
+   */
+  public DatagramSocket(int port, InetAddress addr) throws SocketException
+  {
+    this(new InetSocketAddress(addr, port));
+  }
+
+  /**
+   * Initializes a new instance of <code>DatagramSocket</code> that binds to
+   * the specified local port and address.
+   *
+   * @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.
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.4
+   */
+  public DatagramSocket(SocketAddress address) throws SocketException
+  {
+    String propVal = SystemProperties.getProperty("impl.prefix");
+    if (propVal == null || propVal.equals(""))
+      {
+        if (factory != null)
+          impl = factory.createDatagramSocketImpl();
+        else
+          impl = new PlainDatagramSocketImpl();
+      }
+    else
+      try
+        {
+	  impl =
+	    (DatagramSocketImpl) Class.forName("java.net." + propVal
+	                                       + "DatagramSocketImpl")
+	                              .newInstance();
+        }
+      catch (Exception e)
+        {
+	  System.err.println("Could not instantiate class: java.net."
+	                     + propVal + "DatagramSocketImpl");
+	  impl = new PlainDatagramSocketImpl();
+        }
+
+    if (address != null)
+      bind(address);
+  }
+
+  // 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)
+      {
+	SocketException se = new SocketException();
+	se.initCause(e);
+	throw se;
+      }
+  }
+
+  /**
+   * Closes this datagram socket.
+   */
+  public void close()
+  {
+    if (isClosed())
+      return;
+
+    try
+      {
+	getImpl().close();
+      }
+    catch (SocketException e)
+      {
+	// Ignore this case, just close the socket in finally clause.
+      }
+    finally
+      {
+	remoteAddress = null;
+	remotePort = -1;
+	impl = null;
+      }
+
+    try
+      {
+	if (getChannel() != null)
+	  getChannel().close();
+      }
+    catch (IOException e)
+      {
+	// Do nothing.
+      }
+  }
+
+  /**
+   * This method returns the remote address to which this socket is
+   * connected.  If this socket is not connected, then this method will
+   * return <code>null</code>.
+   *
+   * @return The remote address.
+   *
+   * @since 1.2
+   */
+  public InetAddress getInetAddress()
+  {
+    return remoteAddress;
+  }
+
+  /**
+   * This method returns the remote port to which this socket is
+   * connected.  If this socket is not connected, then this method will
+   * return -1.
+   *
+   * @return The remote port.
+   *
+   * @since 1.2
+   */
+  public int getPort()
+  {
+    return remotePort;
+  }
+
+  /**
+   * 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()
+  {
+    if (! isBound())
+      return null;
+
+    InetAddress localAddr;
+
+    try
+      {
+	localAddr =
+	  (InetAddress) getImpl().getOption(SocketOptions.SO_BINDADDR);
+
+	SecurityManager s = System.getSecurityManager();
+	if (s != null)
+	  s.checkConnect(localAddr.getHostName(), -1);
+      }
+    catch (SecurityException e)
+      {
+	localAddr = InetAddress.ANY_IF;
+      }
+    catch (SocketException e)
+      {
+	// This cannot happen as we are bound.
+	return null;
+      }
+
+    return localAddr;
+  }
+
+  /**
+   * Returns the local port this socket is bound to.
+   *
+   * @return The local port number.
+   */
+  public int getLocalPort()
+  {
+    if (isClosed())
+      return -1;
+
+    try
+      {
+	return getImpl().getLocalPort();
+      }
+    catch (SocketException e)
+      {
+	// This cannot happen as we are bound.
+	return 0;
+      }
+  }
+
+  /**
+   * Returns the value of the socket's SO_TIMEOUT setting.  If this method
+   * returns 0 then SO_TIMEOUT is disabled.
+   *
+   * @return The current timeout in milliseconds.
+   *
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.1
+   */
+  public synchronized int getSoTimeout() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.SO_TIMEOUT);
+
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * Sets the value of the socket's SO_TIMEOUT value.  A value of 0 will
+   * disable SO_TIMEOUT.  Any other value is the number of milliseconds
+   * a socket read/write will block before timing out.
+   *
+   * @param timeout The new SO_TIMEOUT value in milliseconds.
+   *
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.1
+   */
+  public synchronized void setSoTimeout(int timeout) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (timeout < 0)
+      throw new IllegalArgumentException("Invalid timeout: " + timeout);
+
+    getImpl().setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
+  }
+
+  /**
+   * This method returns the value of the system level socket option
+   * SO_SNDBUF, which is used by the operating system to tune buffer
+   * sizes for data transfers.
+   *
+   * @return The send buffer size.
+   *
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.2
+   */
+  public int getSendBufferSize() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.SO_SNDBUF);
+
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * This method sets the value for the system level socket option
+   * SO_SNDBUF to the specified value.  Note that valid values for this
+   * option are specific to a given operating system.
+   *
+   * @param size The new send buffer size.
+   *
+   * @exception SocketException If an error occurs.
+   * @exception IllegalArgumentException If size is 0 or negative.
+   *
+   * @since 1.2
+   */
+  public void setSendBufferSize(int size) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (size < 0)
+      throw new IllegalArgumentException("Buffer size is less than 0");
+
+    getImpl().setOption(SocketOptions.SO_SNDBUF, new Integer(size));
+  }
+
+  /**
+   * This method returns the value of the system level socket option
+   * SO_RCVBUF, which is used by the operating system to tune buffer
+   * sizes for data transfers.
+   *
+   * @return The receive buffer size.
+   *
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.2
+   */
+  public int getReceiveBufferSize() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.SO_RCVBUF);
+
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * This method sets the value for the system level socket option
+   * SO_RCVBUF to the specified value.  Note that valid values for this
+   * option are specific to a given operating system.
+   *
+   * @param size The new receive buffer size.
+   *
+   * @exception SocketException If an error occurs.
+   * @exception IllegalArgumentException If size is 0 or negative.
+   *
+   * @since 1.2
+   */
+  public void setReceiveBufferSize(int size) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (size < 0)
+      throw new IllegalArgumentException("Buffer size is less than 0");
+
+    getImpl().setOption(SocketOptions.SO_RCVBUF, new Integer(size));
+  }
+
+  /**
+   * This method connects this socket to the specified address and port.
+   * When a datagram socket is connected, it will only send or receive
+   * packets to and from the host to which it is connected. A multicast
+   * socket that is connected may only send and not receive packets.
+   *
+   * @param address The address to connect this socket to.
+   * @param port The port to connect this socket to.
+   *
+   * @exception IllegalArgumentException If address or port are invalid.
+   * @exception SecurityException If the caller is not allowed to send
+   * datagrams to or receive from this address and port.
+   *
+   * @since 1.2
+   */
+  public void connect(InetAddress address, int port)
+  {
+    if (address == null)
+      throw new IllegalArgumentException("Connect address may not be null");
+
+    if ((port < 1) || (port > 65535))
+      throw new IllegalArgumentException("Port number is illegal: " + port);
+
+    SecurityManager sm = System.getSecurityManager();
+    if (sm != null)
+      sm.checkConnect(address.getHostName(), port);
+
+    try
+      {
+	getImpl().connect(address, port);
+	remoteAddress = address;
+	remotePort = port;
+      }
+    catch (SocketException e)
+      {
+	// This means simply not connected or connect not implemented.
+      }
+  }
+
+  /**
+   * This method disconnects this socket from the address/port it was
+   * connected to.  If the socket was not connected in the first place,
+   * this method does nothing.
+   *
+   * @since 1.2
+   */
+  public void 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
+   * will block until a packet is received from the network.  On return,
+   * the passed in <code>DatagramPacket</code> is populated with the data
+   * received and all the other information about the packet.
+   *
+   * @param p A <code>DatagramPacket</code> for storing the data
+   *
+   * @exception IOException If an error occurs.
+   * @exception SocketTimeoutException If setSoTimeout was previously called
+   * and the timeout has expired.
+   * @exception PortUnreachableException If the socket is connected to a
+   * currently unreachable destination. Note, there is no guarantee that the
+   * exception will be thrown.
+   * @exception IllegalBlockingModeException If this socket has an associated
+   * channel, and the channel is in non-blocking mode.
+   * @exception SecurityException If a security manager exists and its
+   * checkAccept method doesn't allow the receive.
+   */
+  public synchronized void receive(DatagramPacket p) throws IOException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (remoteAddress != null && remoteAddress.isMulticastAddress())
+      throw new IOException
+	("Socket connected to a multicast address my not receive");
+
+    if (getChannel() != null && ! getChannel().isBlocking()
+        && ! ((DatagramChannelImpl) getChannel()).isInChannelOperation())
+      throw new IllegalBlockingModeException();
+
+    getImpl().receive(p);
+
+    SecurityManager s = System.getSecurityManager();
+    if (s != null && isConnected())
+      s.checkAccept(p.getAddress().getHostName(), p.getPort());
+  }
+
+  /**
+   * Sends the specified packet.  The host and port to which the packet
+   * are to be sent should be set inside the packet.
+   *
+   * @param p The datagram packet to send.
+   *
+   * @exception IOException If an error occurs.
+   * @exception SecurityException If a security manager exists and its
+   * checkMulticast or checkConnect method doesn't allow the send.
+   * @exception PortUnreachableException If the socket is connected to a
+   * currently unreachable destination. Note, there is no guarantee that the
+   * exception will be thrown.
+   * @exception IllegalBlockingModeException If this socket has an associated
+   * channel, and the channel is in non-blocking mode.
+   */
+  public void send(DatagramPacket p) throws IOException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    // JDK1.2: Don't do security checks if socket is connected; see jdk1.2 api.
+    SecurityManager s = System.getSecurityManager();
+    if (s != null && ! isConnected())
+      {
+	InetAddress addr = p.getAddress();
+	if (addr.isMulticastAddress())
+	  s.checkMulticast(addr);
+	else
+	  s.checkConnect(addr.getHostAddress(), p.getPort());
+      }
+
+    if (isConnected())
+      {
+	if (p.getAddress() != null
+	    && (remoteAddress != p.getAddress() || remotePort != p.getPort()))
+	  throw new IllegalArgumentException
+	    ("DatagramPacket address does not match remote address");
+      }
+
+    // FIXME: if this is a subclass of MulticastSocket,
+    // use getTimeToLive for TTL val.
+    if (getChannel() != null && ! getChannel().isBlocking()
+        && ! ((DatagramChannelImpl) getChannel()).isInChannelOperation())
+      throw new IllegalBlockingModeException();
+
+    getImpl().send(p);
+  }
+
+  /**
+   * Binds the socket to the given socket address.
+   *
+   * @param address The socket address to bind to.
+   *
+   * @exception SocketException If an error occurs.
+   * @exception SecurityException If a security manager exists and
+   * its checkListen method doesn't allow the operation.
+   * @exception IllegalArgumentException If address type is not supported.
+   *
+   * @since 1.4
+   */
+  public void bind(SocketAddress address) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (! (address instanceof InetSocketAddress))
+      throw new IllegalArgumentException("unsupported address type");
+
+    InetAddress addr = ((InetSocketAddress) address).getAddress();
+    int port = ((InetSocketAddress) address).getPort();
+
+    if (port < 0 || port > 65535)
+      throw new IllegalArgumentException("Invalid port: " + port);
+
+    SecurityManager s = System.getSecurityManager();
+    if (s != null)
+      s.checkListen(port);
+
+    if (addr == null)
+      addr = InetAddress.ANY_IF;
+
+    try
+      {
+	getImpl().bind(port, addr);
+	bound = true;
+      }
+    catch (SocketException exception)
+      {
+	getImpl().close();
+	throw exception;
+      }
+    catch (RuntimeException exception)
+      {
+	getImpl().close();
+	throw exception;
+      }
+    catch (Error error)
+      {
+	getImpl().close();
+	throw error;
+      }
+  }
+
+  /**
+   * Checks if the datagram socket is closed.
+   *
+   * @return True if socket is closed, false otherwise.
+   *
+   * @since 1.4
+   */
+  public boolean isClosed()
+  {
+    return impl == null;
+  }
+
+  /**
+   * Returns the datagram channel assoziated with this datagram socket.
+   *
+   * @return The associated <code>DatagramChannel</code> object or null
+   *
+   * @since 1.4
+   */
+  public DatagramChannel getChannel()
+  {
+    return null;
+  }
+
+  /**
+   * Connects the datagram socket to a specified socket address.
+   *
+   * @param address The socket address to connect to.
+   *
+   * @exception SocketException If an error occurs.
+   * @exception IllegalArgumentException If address type is not supported.
+   *
+   * @since 1.4
+   */
+  public void connect(SocketAddress address) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (! (address instanceof InetSocketAddress))
+      throw new IllegalArgumentException("unsupported address type");
+
+    InetSocketAddress tmp = (InetSocketAddress) address;
+    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()
+  {
+    return bound;
+  }
+
+  /**
+   * Returns the connection state of the socket.
+   *
+   * @return True if socket is connected, false otherwise.
+   *
+   * @since 1.4
+   */
+  public boolean isConnected()
+  {
+    return remoteAddress != null;
+  }
+
+  /**
+   * 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()
+  {
+    if (! isConnected())
+      return null;
+
+    return new InetSocketAddress(remoteAddress, remotePort);
+  }
+
+  /**
+   * 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()
+  {
+    if (! isBound())
+      return null;
+
+    return new InetSocketAddress(getLocalAddress(), getLocalPort());
+  }
+
+  /**
+   * Enables/Disables SO_REUSEADDR.
+   *
+   * @param on Whether or not to have SO_REUSEADDR turned on.
+   *
+   * @exception SocketException If an error occurs.
+   *
+   * @since 1.4
+   */
+  public void setReuseAddress(boolean on) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    getImpl().setOption(SocketOptions.SO_REUSEADDR, Boolean.valueOf(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
+   */
+  public boolean getReuseAddress() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.SO_REUSEADDR);
+
+    if (buf instanceof Boolean)
+      return ((Boolean) buf).booleanValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * Enables/Disables SO_BROADCAST
+   *
+   * @param enable True if SO_BROADCAST should be enabled, false otherwise.
+   *
+   * @exception SocketException If an error occurs
+   *
+   * @since 1.4
+   */
+  public void setBroadcast(boolean enable) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    getImpl().setOption(SocketOptions.SO_BROADCAST, Boolean.valueOf(enable));
+  }
+
+  /**
+   * Checks if SO_BROADCAST is enabled
+   *
+   * @return Whether SO_BROADCAST is set
+   *
+   * @exception SocketException If an error occurs
+   *
+   * @since 1.4
+   */
+  public boolean getBroadcast() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.SO_BROADCAST);
+
+    if (buf instanceof Boolean)
+      return ((Boolean) buf).booleanValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * Sets the traffic class value
+   *
+   * @param tc The traffic class
+   *
+   * @exception SocketException If an error occurs
+   * @exception IllegalArgumentException If tc value is illegal
+   *
+   * @see DatagramSocket#getTrafficClass()
+   *
+   * @since 1.4
+   */
+  public void setTrafficClass(int tc) throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    if (tc < 0 || tc > 255)
+      throw new IllegalArgumentException();
+
+    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
+   *
+   * @since 1.4
+   */
+  public int getTrafficClass() throws SocketException
+  {
+    if (isClosed())
+      throw new SocketException("socket is closed");
+
+    Object buf = getImpl().getOption(SocketOptions.IP_TOS);
+
+    if (buf instanceof Integer)
+      return ((Integer) buf).intValue();
+
+    throw new SocketException("unexpected type");
+  }
+
+  /**
+   * Sets the datagram socket implementation factory for the application
+   *
+   * @param fac The factory to set
+   *
+   * @exception IOException If an error occurs
+   * @exception SocketException If the factory is already defined
+   * @exception SecurityException If a security manager exists and its
+   * checkSetFactory method doesn't allow the operation
+   */
+  public static void setDatagramSocketImplFactory(DatagramSocketImplFactory fac)
+    throws IOException
+  {
+    if (factory != null)
+      throw new SocketException("DatagramSocketImplFactory already defined");
+
+    SecurityManager sm = System.getSecurityManager();
+    if (sm != null)
+      sm.checkSetFactory();
+
+    factory = fac;
+  }
+}