001/* DatagramChannel.java --
002   Copyright (C) 2002 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038package java.nio.channels;
039
040import java.io.IOException;
041import java.net.DatagramSocket;
042import java.net.SocketAddress;
043import java.nio.ByteBuffer;
044import java.nio.channels.spi.AbstractSelectableChannel;
045import java.nio.channels.spi.SelectorProvider;
046
047
048/**
049 * @since 1.4
050 */
051public 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}