socket.java

gcc的组建

    if (! (endpoint instanceof InetSocketAddress))
      throw new IllegalArgumentException("unsupported address type");

    // The Sun spec says that if we have an associated channel and
    // it is in non-blocking mode, we throw an IllegalBlockingModeException.
    // However, in our implementation if the channel itself initiated this
    // operation, then we must honor it regardless of its blocking mode.
    if (getChannel() != null && ! getChannel().isBlocking()
        && ! ((PlainSocketImpl) getImpl()).isInChannelOperation())
      throw new IllegalBlockingModeException();

    if (! isBound())
      bind(null);

    getImpl().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 (! isConnected())
      return null;

    try
      {
	return getImpl().getInetAddress();
      }
    catch (SocketException e)
      {
	// This cannot happen as we are connected.
      }

    return null;
  }

  /**
   * Returns the local address to which this socket is bound.  If this socket
   * is not connected, then a wildcard address, for which
   * @see InetAddress#isAnyLocalAddress() is <code>true</code>, is returned.
   *
   * @return The local address
   *
   * @since 1.1
   */
  public InetAddress getLocalAddress()
  {
    if (! isBound())
      return InetAddress.ANY_IF;

    InetAddress addr = null;

    try
      {
	addr = (InetAddress) getImpl().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 0 is returned.
   *
   * @return The remote port this socket is connected to
   */
  public int getPort()
  {
    if (! isConnected())
      return 0;

    try
      {
	return getImpl().getPort();
      }
    catch (SocketException e)
      {
	// This cannot happen as we are connected.
      }

    return 0;
  }

  /**
   * 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 (! isBound())
      return -1;

    try
      {
	if (getImpl() != null)
	  return getImpl().getLocalPort();
      }
    catch (SocketException e)
      {
	// This cannot happen as we are bound.
      }

    return -1;
  }

  /**
   * Returns local socket address.
   *
   * @return the local socket address, null if not bound
   *
   * @since 1.4
   */
  public SocketAddress getLocalSocketAddress()
  {
    if (! isBound())
      return null;

    InetAddress addr = getLocalAddress();

    try
      {
	return new InetSocketAddress(addr, getImpl().getLocalPort());
      }
    catch (SocketException e)
      {
	// This cannot happen as we are bound.
	return null;
      }
  }

  /**
   * Returns the remote socket address.
   *
   * @return the remote socket address, null of not connected
   *
   * @since 1.4
   */
  public SocketAddress getRemoteSocketAddress()
  {
    if (! isConnected())
      return null;

    try
      {
	return new InetSocketAddress(getImpl().getInetAddress(),
	                             getImpl().getPort());
      }
    catch (SocketException e)
      {
	// This cannot happen as we are connected.
	return null;
      }
  }

  /**
   * 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 (isClosed())
      throw new SocketException("socket is closed");

    if (! isConnected())
      throw new IOException("not connected");

    return getImpl().getInputStream();
  }

  /**
   * 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 (isClosed())
      throw new SocketException("socket is closed");

    if (! isConnected())
      throw new IOException("not connected");

    return getImpl().getOutputStream();
  }

  /**
   * 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 (isClosed())
      throw new SocketException("socket is closed");

    getImpl().setOption(SocketOptions.TCP_NODELAY, Boolean.valueOf(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 (isClosed())
      throw new SocketException("socket is closed");

    Object on = getImpl().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 (isClosed())
      throw new SocketException("socket is closed");

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

	if (linger > 65535)
	  linger = 65535;

	getImpl().setOption(SocketOptions.SO_LINGER, new Integer(linger));
      }
    else
      getImpl().setOption(SocketOptions.SO_LINGER, Boolean.valueOf(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 (isClosed())
      throw new SocketException("socket is closed");

    Object linger = getImpl().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
  {
    if (isClosed())
      throw new SocketException("socket is closed");

    getImpl().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 (isClosed())
      throw new SocketException("socket is closed");

    getImpl().setOption(SocketOptions.SO_OOBINLINE, Boolean.valueOf(on));
  }

  /**
   * Returns the current setting of the SO_OOBINLINE option for this socket
   *
   * @return True if SO_OOBINLINE is set, false otherwise.
   *
   * @exception SocketException If an error occurs
   *
   * @since 1.4
   */
  public boolean getOOBInline() throws SocketException
  {
    if (isClosed())
      throw new SocketException("socket is closed");

    Object buf = getImpl().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 milliseconds.
   *
   * @param timeout The length of the timeout in milliseconds, or
   * 0 to indicate no timeout.
   *
   * @exception SocketException If an error occurs or Socket not connected
   *
   * @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("SO_TIMEOUT value must be >= 0");

    getImpl().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
  {