001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.net.discard;
019    
020    import java.io.IOException;
021    import java.net.DatagramPacket;
022    import java.net.InetAddress;
023    
024    import org.apache.commons.net.DatagramSocketClient;
025    
026    /***
027     * The DiscardUDPClient class is a UDP implementation of a client for the
028     * Discard protocol described in RFC 863.  To use the class,
029     * just open a local UDP port
030     * with {@link org.apache.commons.net.DatagramSocketClient#open  open }
031     * and call {@link #send  send } to send datagrams to the server
032     * After you're done sending discard data, call
033     * {@link org.apache.commons.net.DatagramSocketClient#close  close() }
034     * to clean up properly.
035     * <p>
036     * <p>
037     * @author Daniel F. Savarese
038     * @see DiscardTCPClient
039     ***/
040    
041    public class DiscardUDPClient extends DatagramSocketClient
042    {
043        /*** The default discard port.  It is set to 9 according to RFC 863. ***/
044        public static final int DEFAULT_PORT = 9;
045    
046        DatagramPacket _sendPacket;
047    
048        public DiscardUDPClient()
049        {
050            _sendPacket = new DatagramPacket(new byte[0], 0);
051        }
052    
053    
054        /***
055         * Sends the specified data to the specified server at the specified port.
056         * <p>
057         * @param data  The discard data to send.
058         * @param length  The length of the data to send.  Should be less than
059         *    or equal to the length of the data byte array.
060         * @param host  The address of the server.
061         * @param port  The service port.
062         * @exception IOException If an error occurs during the datagram send
063         *            operation.
064         ***/
065        public void send(byte[] data, int length, InetAddress host, int port)
066        throws IOException
067        {
068            _sendPacket.setData(data);
069            _sendPacket.setLength(length);
070            _sendPacket.setAddress(host);
071            _sendPacket.setPort(port);
072            _socket_.send(_sendPacket);
073        }
074    
075    
076        /***
077         * Same as
078         * <code>send(data, length, host. DiscardUDPClient.DEFAULT_PORT)</code>.
079         ***/
080        public void send(byte[] data, int length, InetAddress host)
081        throws IOException
082        {
083            send(data, length, host, DEFAULT_PORT);
084        }
085    
086    
087        /***
088         * Same as
089         * <code>send(data, data.length, host. DiscardUDPClient.DEFAULT_PORT)</code>.
090         ***/
091        public void send(byte[] data, InetAddress host) throws IOException
092        {
093            send(data, data.length, host, DEFAULT_PORT);
094        }
095    
096    }
097