socket.java

this gcc-g++-3.3.1.tar.gz is a source file of gcc, you can learn more about gcc through this codes f

   */
  public void connect (SocketAddress endpoint, int timeout)
    throws IOException
  {
    if (closed)
      throw new SocketException ("Socket is closed");
    
    if (! (endpoint instanceof InetSocketAddress))
      throw new IllegalArgumentException ("Address type not supported");

    if (ch != null && !ch.isBlocking ())
      throw new IllegalBlockingModeException ();
    
    impl.connect (endpoint, timeout);
  }

  /**
   * Returns the address of the remote end of the socket.  If this socket
   * is not connected, then <code>null</code> is returned.
   *
   * @return The remote address this socket is connected to
   */
  public InetAddress getInetAddress ()
  {
    if (impl != null)
      return impl.getInetAddress();

    return null;
  }

  /**
   * Returns the local address to which this socket is bound.  If this socket
   * is not connected, then <code>null</code> is returned.
   *
   * @return The local address
   *
   * @since 1.1
   */
  public InetAddress getLocalAddress ()
  {
    if (impl == null)
      return null;

    InetAddress addr = null;
    try
      {
        addr = (InetAddress)impl.getOption(SocketOptions.SO_BINDADDR);
      }
    catch(SocketException e)
      {
        // (hopefully) shouldn't happen
        // throw new java.lang.InternalError
        //      ("Error in PlainSocketImpl.getOption");
        return null;
      }

    // FIXME: According to libgcj, checkConnect() is supposed to be called
    // before performing this operation.  Problems: 1) We don't have the
    // addr until after we do it, so we do a post check.  2). The docs I
    // see don't require this in the Socket case, only DatagramSocket, but
    // we'll assume they mean both.
    SecurityManager sm = System.getSecurityManager();
    if (sm != null)
      sm.checkConnect(addr.getHostName(), getLocalPort());

    return addr;
  }

  /**
   * Returns the port number of the remote end of the socket connection.  If
   * this socket is not connected, then -1 is returned.
   *
   * @return The remote port this socket is connected to
   */
  public int getPort ()
  {
    if (impl != null)
      return impl.getPort();

    return -1;
  }

  /**
   * Returns the local port number to which this socket is bound.  If this
   * socket is not connected, then -1 is returned.
   *
   * @return The local port
   */
  public int getLocalPort ()
  {
    if (impl != null)
      return impl.getLocalPort();

    return -1;
  }

  /**
   * If the socket is already bound this returns the local SocketAddress,
   * otherwise null
   *
   * @since 1.4
   */
  public SocketAddress getLocalSocketAddress()
  {
    InetAddress addr = getLocalAddress ();

    if (addr == null)
      return null;
    
    return new InetSocketAddress (addr, impl.getLocalPort());
  }

  /**
   * If the socket is already connected this returns the remote SocketAddress,
   * otherwise null
   *
   * @since 1.4
   */
  public SocketAddress getRemoteSocketAddress()
  {
    if (!isConnected ())
      return null;

    return new InetSocketAddress (impl.getInetAddress (), impl.getPort ());
  }

  /**
   * Returns an InputStream for reading from this socket.
   *
   * @return The InputStream object
   *
   * @exception IOException If an error occurs or Socket is not connected
   */
  public InputStream getInputStream () throws IOException
  {
    if (impl != null)
      return(impl.getInputStream());

    throw new IOException("Not connected");
  }

  /**
   * Returns an OutputStream for writing to this socket.
   *
   * @return The OutputStream object
   *
   * @exception IOException If an error occurs or Socket is not connected
   */
  public OutputStream getOutputStream () throws IOException
  {
    if (impl != null)
      return impl.getOutputStream();

    throw new IOException("Not connected");
  }

  /**
   * Sets the TCP_NODELAY option on the socket. 
   *
   * @param on true to enable, false to disable
   * 
   * @exception SocketException If an error occurs or Socket is not connected
   *
   * @since 1.1
   */
  public void setTcpNoDelay (boolean on)  throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");

    impl.setOption(SocketOptions.TCP_NODELAY, new Boolean(on));
  }

  /**
   * Tests whether or not the TCP_NODELAY option is set on the socket. 
   * Returns true if enabled, false if disabled. When on it disables the
   * Nagle algorithm which means that packets are always send immediatly and
   * never merged together to reduce network trafic.
   *
   * @return Whether or not TCP_NODELAY is set
   * 
   * @exception SocketException If an error occurs or Socket not connected
   *
   * @since 1.1
   */
  public boolean getTcpNoDelay() throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");

    Object on = impl.getOption(SocketOptions.TCP_NODELAY);
  
    if (on instanceof Boolean)
      return(((Boolean)on).booleanValue());
    else
      throw new SocketException("Internal Error");
  }

  /**
   * Sets the value of the SO_LINGER option on the socket.  If the 
   * SO_LINGER option is set on a socket and there is still data waiting to
   * be sent when the socket is closed, then the close operation will block
   * until either that data is delivered or until the timeout period
   * expires.  The linger interval is specified in hundreths of a second
   * (platform specific?)
   *
   * @param on true to enable SO_LINGER, false to disable
   * @param linger The SO_LINGER timeout in hundreths of a second or -1 if 
   * SO_LINGER not set.
   *
   * @exception SocketException If an error occurs or Socket not connected
   * @exception IllegalArgumentException If linger is negative
   *
   * @since 1.1
   */
  public void setSoLinger(boolean on, int linger) throws SocketException
  {
    if (impl == null)
      throw new SocketException("No socket created");

    if (on == true)
      {
        if (linger < 0)
          throw new IllegalArgumentException("SO_LINGER must be >= 0");

        if (linger > 65535)
          linger = 65535;

        impl.setOption(SocketOptions.SO_LINGER, new Integer(linger));
      }
    else
      {
        impl.setOption(SocketOptions.SO_LINGER, new Boolean(false));
      }
  }

  /**
   * Returns the value of the SO_LINGER option on the socket.  If the 
   * SO_LINGER option is set on a socket and there is still data waiting to
   * be sent when the socket is closed, then the close operation will block
   * until either that data is delivered or until the timeout period
   * expires.  This method either returns the timeouts (in hundredths of
   * of a second (platform specific?)) if SO_LINGER is set, or -1 if
   * SO_LINGER is not set.
   *
   * @return The SO_LINGER timeout in hundreths of a second or -1 
   * if SO_LINGER not set
   *
   * @exception SocketException If an error occurs or Socket is not connected
   *
   * @since 1.1
   */
  public int getSoLinger() throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");

    Object linger = impl.getOption(SocketOptions.SO_LINGER);
    if (linger instanceof Integer)
      return(((Integer)linger).intValue());
    else
      return -1;
  }

  /**
   * Sends urgent data through the socket
   *
   * @param data The data to send.
   * Only the lowest eight bits of data are sent
   *
   * @exception IOException If an error occurs
   *
   * @since 1.4
   */
  public void sendUrgentData (int data) throws IOException
  {
    impl.sendUrgentData (data);
  }

  /**
   * Enables/disables the SO_OOBINLINE option
   * 
   * @param on True if SO_OOBLINE should be enabled 
   * 
   * @exception SocketException If an error occurs
   * 
   * @since 1.4
   */
  public void setOOBInline (boolean on) throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");

    impl.setOption(SocketOptions.SO_OOBINLINE, new Boolean(on));
  }

  /**
   * Returns the current setting of the SO_OOBINLINE option for this socket
   * 
   * @exception SocketException If an error occurs
   * 
   * @since 1.4
   */
  public boolean getOOBInline () throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");

    Object buf = impl.getOption(SocketOptions.SO_OOBINLINE);

    if (buf instanceof Boolean)
      return(((Boolean)buf).booleanValue());
    else
      throw new SocketException("Internal Error: Unexpected type");
  }
  
  /**
   * Sets the value of the SO_TIMEOUT option on the socket.  If this value
   * is set, and an read/write is performed that does not complete within
   * the timeout period, a short count is returned (or an EWOULDBLOCK signal
   * would be sent in Unix if no data had been read).  A value of 0 for
   * this option implies that there is no timeout (ie, operations will 
   * block forever).  On systems that have separate read and write timeout
   * values, this method returns the read timeout.  This
   * value is in thousandths of a second (****????*****)
   *
   * @param timeout The length of the timeout in thousandth's of a second or 
   * 0 if not set
   *
   * @exception SocketException If an error occurs or Socket not connected
   *
   * @since 1.1
   */
  public synchronized void setSoTimeout (int timeout) throws SocketException
  {
    if (impl == null)
      throw new SocketException("Not connected");
    
    if (timeout < 0)
      throw new IllegalArgumentException("SO_TIMEOUT value must be >= 0");
      
    impl.setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
  }

  /**
   * Returns the value of the SO_TIMEOUT option on the socket.  If this value
   * is set, and an read/write is performed that does not complete within
   * the timeout period, a short count is returned (or an EWOULDBLOCK signal
   * would be sent in Unix if no data had been read).  A value of 0 for
   * this option implies that there is no timeout (ie, operations will 
   * block forever).  On systems that have separate read and write timeout
   * values, this method returns the read timeout.  This
   * value is in thousandths of a second (implementation specific?).
   *
   * @return The length of the timeout in thousandth's of a second or 0 
   * if not set
   *
   * @exception SocketException If an error occurs or Socket not connected
   *
   * @since 1.1
   */
  public synchronized int getSoTimeout () throws SocketException
  {
    if (impl == null) 
      throw new SocketException("Not connected");

    Object timeout = impl.getOption(SocketOptions.SO_TIMEOUT);
    if (timeout instanceof Integer)
      return(((Integer)timeout).intValue());
    else