001    /* SocketChannel.java --
002       Copyright (C) 2002, 2004  Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package java.nio.channels;
040    
041    import java.io.IOException;
042    import java.net.Socket;
043    import java.net.SocketAddress;
044    import java.nio.ByteBuffer;
045    import java.nio.channels.spi.AbstractSelectableChannel;
046    import java.nio.channels.spi.SelectorProvider;
047    
048    /**
049     * @author Michael Koch (konqueror@gmx.de)
050     * @since 1.4
051     */
052    public abstract class SocketChannel extends AbstractSelectableChannel
053      implements ByteChannel, ScatteringByteChannel, GatheringByteChannel
054    {
055      /**
056       * Initializes this socket channel.
057       */
058      protected SocketChannel(SelectorProvider provider)
059      {
060        super(provider);
061      }
062    
063      /**
064       * Opens a socket channel.
065       *
066       * @return the new <code>SocketChannel</code> object
067       * 
068       * @exception IOException If an error occurs
069       */
070      public static SocketChannel open() throws IOException
071      {
072        return SelectorProvider.provider().openSocketChannel();
073      }
074    
075      /**
076       * Opens a channel and connects it to a remote address.
077       *
078       * @return the new <code>SocketChannel</code> object
079       * 
080       * @exception AsynchronousCloseException If this channel is already connected.
081       * @exception ClosedByInterruptException If another thread interrupts the
082       * current thread while the connect operation is in progress, thereby closing
083       * the channel and setting the current thread's interrupt status.
084       * @exception IOException If an error occurs
085       * @exception SecurityException If a security manager has been installed and
086       * it does not permit access to the given remote endpoint.
087       * @exception UnresolvedAddressException If the given remote address is not
088       * fully resolved.
089       * @exception UnsupportedAddressTypeException If the type of the given remote
090       * address is not supported.
091       */
092      public static SocketChannel open(SocketAddress remote)
093        throws IOException
094      {
095        SocketChannel ch = open();
096        ch.connect(remote);
097        return ch;
098      }
099    
100      /**
101       * Reads data from the channel.
102       *
103       * @return the number of bytes read, zero is valid too, -1 if end of stream
104       * is reached
105       *
106       * @exception IOException If an error occurs
107       * @exception NotYetConnectedException If this channel is not yet connected.
108       */
109      public final long read(ByteBuffer[] dsts) throws IOException
110      {
111        long b = 0;
112    
113        for (int i = 0; i < dsts.length; i++)
114          b += read(dsts[i]);
115    
116        return b;
117      }
118    
119      /**
120       * Writes data to the channel.
121       *
122       * @return the number of bytes written, zero is valid too
123       * 
124       * @exception IOException If an error occurs
125       * @exception NotYetConnectedException If this channel is not yet connected.
126       */
127      public final long write(ByteBuffer[] dsts) throws IOException
128      {
129        long b = 0;
130    
131        for (int i = 0; i < dsts.length; i++)
132          b += write(dsts[i]);
133    
134        return b;
135      }
136    
137      /**
138       * Retrieves the valid operations for this channel.
139       *
140       * @return the valid operations
141       */
142      public final int validOps()
143      {
144        return SelectionKey.OP_CONNECT | SelectionKey.OP_READ
145               | SelectionKey.OP_WRITE;
146      }
147    
148      /**
149       * Reads data from the channel.
150       *
151       * @return the number of bytes read, zero is valid too, -1 if end of stream
152       * is reached
153       * 
154       * @exception IOException If an error occurs
155       * @exception NotYetConnectedException If this channel is not yet connected.
156       */
157      public abstract int read(ByteBuffer dst) throws IOException;
158    
159      /**
160       * Connects the channel's socket to the remote address.
161       *
162       * @return <code>true</code> if the channel got successfully connected,
163       * <code>false</code> if the channel is in non-blocking mode and connection
164       * operation is still in progress.
165       * 
166       * @exception AlreadyConnectedException If this channel is already connected.
167       * @exception AsynchronousCloseException If this channel is already connected.
168       * @exception ClosedByInterruptException If another thread interrupts the
169       * current thread while the connect operation is in progress, thereby closing
170       * the channel and setting the current thread's interrupt status.
171       * @exception ClosedChannelException If this channel is closed.
172       * @exception ConnectionPendingException If a non-blocking connection
173       * operation is already in progress on this channel.
174       * @exception IOException If an error occurs
175       * @exception SecurityException If a security manager has been installed and
176       * it does not permit access to the given remote endpoint.
177       * @exception UnresolvedAddressException If the given remote address is not
178       * fully resolved.
179       * @exception UnsupportedAddressTypeException If the type of the given remote
180       * address is not supported.
181       */
182      public abstract boolean connect(SocketAddress remote)
183        throws IOException;
184    
185      /**
186       * Finishes the process of connecting a socket channel.
187       *
188       * @exception AsynchronousCloseException If this channel is already connected.
189       * @exception ClosedByInterruptException If another thread interrupts the
190       * current thread while the connect operation is in progress, thereby closing
191       * the channel and setting the current thread's interrupt status.
192       * @exception ClosedChannelException If this channel is closed.
193       * @exception IOException If an error occurs
194       * @exception NoConnectionPendingException If this channel is not connected
195       * and a connection operation has not been initiated.
196       */
197      public abstract boolean finishConnect() throws IOException;
198    
199      /**
200       * Tells whether or not the channel's socket is connected.
201       */
202      public abstract boolean isConnected();
203    
204      /**
205       * Tells whether or not a connection operation is in progress on this channel.
206       */
207      public abstract boolean isConnectionPending();
208    
209      /**
210       * Reads data from the channel.
211       *
212       * @return the number of bytes read, zero is valid too, -1 if end of stream
213       * is reached
214       * 
215       * @exception IOException If an error occurs
216       * @exception NotYetConnectedException If this channel is not yet connected.
217       */
218      public abstract long read(ByteBuffer[] dsts, int offset, int length)
219        throws IOException;
220    
221      /**
222       * Retrieves the channel's socket.
223       *
224       * @return the socket
225       */
226      public abstract Socket socket();
227    
228      /**
229       * Writes data to the channel.
230       *
231       * @return the number of bytes written, zero is valid too
232       * 
233       * @exception IOException If an error occurs
234       * @exception NotYetConnectedException If this channel is not yet connected.
235       */
236      public abstract int write(ByteBuffer src) throws IOException;
237    
238      /**
239       * Writes data to the channel.
240       *
241       * @return the number of bytes written, zero is valid too
242       * 
243       * @exception IOException If an error occurs
244       * @exception NotYetConnectedException If this channel is not yet connected.
245       */
246      public abstract long write(ByteBuffer[] srcs, int offset, int length)
247        throws IOException;
248    }