gcc/libjava/java/nio/channels/SocketChannel.java

/* SocketChannel.java --
   Copyright (C) 2002, 2004  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
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02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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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
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independent module, the terms and conditions of the license of that
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package java.nio.channels;

import java.io.IOException;
import java.net.Socket;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.spi.AbstractSelectableChannel;
import java.nio.channels.spi.SelectorProvider;

/**
 * @author Michael Koch (konqueror@gmx.de)
 * @since 1.4
 */
public abstract class SocketChannel extends AbstractSelectableChannel
  implements ByteChannel, ScatteringByteChannel, GatheringByteChannel
{
  /**
   * Initializes this socket channel.
   */
  protected SocketChannel(SelectorProvider provider)
  {
    super(provider);
  }

  /**
   * Opens a socket channel.
   *
   * @return the new <code>SocketChannel</code> object
   * 
   * @exception IOException If an error occurs
   */
  public static SocketChannel open() throws IOException
  {
    return SelectorProvider.provider().openSocketChannel();
  }

  /**
   * Opens a channel and connects it to a remote address.
   *
   * @return the new <code>SocketChannel</code> object
   * 
   * @exception AsynchronousCloseException If this channel is already connected.
   * @exception ClosedByInterruptException If another thread interrupts the
   * current thread while the connect operation is in progress, thereby closing
   * the channel and setting the current thread's interrupt status.
   * @exception IOException If an error occurs
   * @exception SecurityException If a security manager has been installed and
   * it does not permit access to the given remote endpoint.
   * @exception UnresolvedAddressException If the given remote address is not
   * fully resolved.
   * @exception UnsupportedAddressTypeException If the type of the given remote
   * address is not supported.
   */
  public static SocketChannel open(SocketAddress remote)
    throws IOException
  {
    SocketChannel ch = open();
    ch.connect(remote);
    return ch;
  }

  /**
   * Reads data from the channel.
   *
   * @return the number of bytes read, zero is valid too, -1 if end of stream
   * is reached
   *
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public final long read(ByteBuffer[] dsts) throws IOException
  {
    long b = 0;

    for (int i = 0; i < dsts.length; i++)
      b += read(dsts[i]);

    return b;
  }

  /**
   * Writes data to the channel.
   *
   * @return the number of bytes written, zero is valid too
   * 
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public final long write(ByteBuffer[] dsts) throws IOException
  {
    long b = 0;

    for (int i = 0; i < dsts.length; i++)
      b += write(dsts[i]);

    return b;
  }

  /**
   * Retrieves the valid operations for this channel.
   *
   * @return the valid operations
   */
  public final int validOps()
  {
    return SelectionKey.OP_CONNECT | SelectionKey.OP_READ
           | SelectionKey.OP_WRITE;
  }

  /**
   * Reads data from the channel.
   *
   * @return the number of bytes read, zero is valid too, -1 if end of stream
   * is reached
   * 
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public abstract int read(ByteBuffer dst) throws IOException;

  /**
   * Connects the channel's socket to the remote address.
   *
   * @return <code>true</code> if the channel got successfully connected,
   * <code>false</code> if the channel is in non-blocking mode and connection
   * operation is still in progress.
   * 
   * @exception AlreadyConnectedException If this channel is already connected.
   * @exception AsynchronousCloseException If this channel is already connected.
   * @exception ClosedByInterruptException If another thread interrupts the
   * current thread while the connect operation is in progress, thereby closing
   * the channel and setting the current thread's interrupt status.
   * @exception ClosedChannelException If this channel is closed.
   * @exception ConnectionPendingException If a non-blocking connection
   * operation is already in progress on this channel.
   * @exception IOException If an error occurs
   * @exception SecurityException If a security manager has been installed and
   * it does not permit access to the given remote endpoint.
   * @exception UnresolvedAddressException If the given remote address is not
   * fully resolved.
   * @exception UnsupportedAddressTypeException If the type of the given remote
   * address is not supported.
   */
  public abstract boolean connect(SocketAddress remote)
    throws IOException;

  /**
   * Finishes the process of connecting a socket channel.
   *
   * @exception AsynchronousCloseException If this channel is already connected.
   * @exception ClosedByInterruptException If another thread interrupts the
   * current thread while the connect operation is in progress, thereby closing
   * the channel and setting the current thread's interrupt status.
   * @exception ClosedChannelException If this channel is closed.
   * @exception IOException If an error occurs
   * @exception NoConnectionPendingException If this channel is not connected
   * and a connection operation has not been initiated.
   */
  public abstract boolean finishConnect() throws IOException;

  /**
   * Tells whether or not the channel's socket is connected.
   */
  public abstract boolean isConnected();

  /**
   * Tells whether or not a connection operation is in progress on this channel.
   */
  public abstract boolean isConnectionPending();

  /**
   * Reads data from the channel.
   *
   * @return the number of bytes read, zero is valid too, -1 if end of stream
   * is reached
   * 
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public abstract long read(ByteBuffer[] dsts, int offset, int length)
    throws IOException;

  /**
   * Retrieves the channel's socket.
   *
   * @return the socket
   */
  public abstract Socket socket();

  /**
   * Writes data to the channel.
   *
   * @return the number of bytes written, zero is valid too
   * 
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public abstract int write(ByteBuffer src) throws IOException;

  /**
   * Writes data to the channel.
   *
   * @return the number of bytes written, zero is valid too
   * 
   * @exception IOException If an error occurs
   * @exception NotYetConnectedException If this channel is not yet connected.
   */
  public abstract long write(ByteBuffer[] srcs, int offset, int length)
    throws IOException;
}