001    /* DatagramChannel.java --
002       Copyright (C) 2002 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    package java.nio.channels;
039    
040    import java.io.IOException;
041    import java.net.DatagramSocket;
042    import java.net.SocketAddress;
043    import java.nio.ByteBuffer;
044    import java.nio.channels.spi.AbstractSelectableChannel;
045    import java.nio.channels.spi.SelectorProvider;
046    
047    
048    /**
049     * @since 1.4
050     */
051    public abstract class DatagramChannel extends AbstractSelectableChannel
052      implements ByteChannel, ScatteringByteChannel, GatheringByteChannel
053    {
054      /**
055       * Initializes the channel.
056       */
057      protected DatagramChannel(SelectorProvider provider)
058      {
059        super(provider);
060      }
061    
062      /**
063       * Opens a datagram channel.
064       *
065       * @exception IOException If an error occurs
066       */
067      public static DatagramChannel open() throws IOException
068      {
069        return SelectorProvider.provider().openDatagramChannel();
070      }
071    
072      /**
073       * Reads data from this channel.
074       */
075      public final long read(ByteBuffer[] dsts) throws IOException
076      {
077        long b = 0;
078    
079        for (int i = 0; i < dsts.length; i++)
080          b += read(dsts[i]);
081    
082        return b;
083      }
084    
085      /**
086       * Writes data to this channel.
087       *
088       * @exception IOException If an error occurs
089       * @exception NotYetConnectedException The channel's socket is not connected.
090       */
091      public final long write(ByteBuffer[] srcs) throws IOException
092      {
093        long b = 0;
094    
095        for (int i = 0; i < srcs.length; i++)
096          b += write(srcs[i]);
097    
098        return b;
099      }
100    
101      /**
102       * Connects this channel's socket.
103       *
104       * @exception AsynchronousCloseException If another thread closes this channel
105       * while the connect operation is in progress.
106       * @exception ClosedByInterruptException If another thread interrupts the
107       * current thread while the read operation is in progress, thereby closing the
108       * channel and setting the current thread's interrupt status.
109       * @exception ClosedChannelException If this channel is closed.
110       * @exception IOException If an error occurs.
111       * @exception SecurityException If a security manager has been installed and
112       * it does not permit datagrams to be sent to the given address.
113       */
114      public abstract DatagramChannel connect(SocketAddress remote)
115        throws IOException;
116    
117      /**
118       * Disonnects this channel's socket.
119       *
120       * @exception IOException If an error occurs
121       */
122      public abstract DatagramChannel disconnect() throws IOException;
123    
124      /**
125       * Tells whether or not this channel's socket is connected.
126       *
127       * @exception NotYetConnectedException The channel's socket is not connected.
128       */
129      public abstract boolean isConnected();
130    
131      /**
132       * Reads data from this channel.
133       */
134      public abstract int read(ByteBuffer dst) throws IOException;
135    
136      /**
137       * Reads data from this channel.
138       *
139       * @exception IOException If an error occurs.
140       * @exception NotYetConnectedException The channel's socket is not connected.
141       */
142      public abstract long read(ByteBuffer[] dsts, int offset, int length)
143        throws IOException;
144    
145      /**
146       * Receives a datagram via this channel.
147       *
148       * @exception AsynchronousCloseException If another thread closes this channel
149       * while the connect operation is in progress.
150       * @exception ClosedByInterruptException If another thread interrupts the
151       * current thread while the read operation is in progress, thereby closing the
152       * channel and setting the current thread's interrupt status.
153       * @exception ClosedChannelException If this channel is closed.
154       * @exception IOException If an error occurs
155       * @exception SecurityException If a security manager has been installed and
156       * it does not permit datagrams to be sent to the given address.
157       */
158      public abstract SocketAddress receive(ByteBuffer dst)
159        throws IOException;
160    
161      /**
162       * Sends a datagram via this channel.
163       *
164       * @exception AsynchronousCloseException If another thread closes this channel
165       * while the connect operation is in progress.
166       * @exception ClosedByInterruptException If another thread interrupts the
167       * current thread while the read operation is in progress, thereby closing the
168       * channel and setting the current thread's interrupt status.
169       * @exception ClosedChannelException If this channel is closed.
170       * @exception IOException If an error occurs
171       * @exception SecurityException If a security manager has been installed and
172       * it does not permit datagrams to be sent to the given address.
173       */
174      public abstract int send(ByteBuffer src, SocketAddress target)
175        throws IOException;
176    
177      /**
178       * Retrieves the channel's socket.
179       */
180      public abstract DatagramSocket socket();
181    
182      /**
183       * Writes data to this channel.
184       *
185       * @exception IOException If an error occurs.
186       * @exception NotYetConnectedException The channel's socket is not connected.
187       */
188      public abstract int write(ByteBuffer src) throws IOException;
189    
190      /**
191       * Writes data to this channel.
192       *
193       * @exception IOException If an error occurs.
194       * @exception NotYetConnectedException The channel's socket is not connected.
195       */
196      public abstract long write(ByteBuffer[] srcs, int offset, int length)
197        throws IOException;
198    
199      /**
200       * Retrieves the valid operations for this channel.
201       *
202       * @exception NotYetConnectedException The channel's socket is not connected.
203       */
204      public final int validOps()
205      {
206        return SelectionKey.OP_READ | SelectionKey.OP_WRITE;
207      }
208    }