    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
    018package org.apache.commons.net.discard;
    019
    020import java.io.IOException;
    021import java.net.DatagramPacket;
    022import java.net.InetAddress;
    023
    024import 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 *
    036 * @see DiscardTCPClient
    037 ***/
    038
    039public class DiscardUDPClient extends DatagramSocketClient
    040{
    041    /*** The default discard port.  It is set to 9 according to RFC 863. ***/
    042    public static final int DEFAULT_PORT = 9;
    043
    044    private final DatagramPacket sendPacket;
    045
    046    public DiscardUDPClient()
    047    {
    048        sendPacket = new DatagramPacket(new byte[0], 0);
    049    }
    050
    051
    052    /***
    053     * Sends the specified data to the specified server at the specified port.
    054     *
    055     * @param data  The discard data to send.
    056     * @param length  The length of the data to send.  Should be less than
    057     *    or equal to the length of the data byte array.
    058     * @param host  The address of the server.
    059     * @param port  The service port.
    060     * @throws IOException If an error occurs during the datagram send
    061     *            operation.
    062     ***/
    063    public void send(final byte[] data, final int length, final InetAddress host, final int port)
    064    throws IOException
    065    {
    066        sendPacket.setData(data);
    067        sendPacket.setLength(length);
    068        sendPacket.setAddress(host);
    069        sendPacket.setPort(port);
    070        _socket_.send(sendPacket);
    071    }
    072
    073
    074    /***
    075     * Same as
    076     * <code>send(data, length, host. DiscardUDPClient.DEFAULT_PORT)</code>.
    077     * @param data the buffer to send
    078     * @param length the length of the data in the buffer
    079     * @param host the target host
    080     * @see #send(byte[], int, InetAddress, int)
    081     * @throws IOException if an error occurs
    082     ***/
    083    public void send(final byte[] data, final int length, final InetAddress host)
    084    throws IOException
    085    {
    086        send(data, length, host, DEFAULT_PORT);
    087    }
    088
    089
    090    /***
    091     * Same as
    092     * <code>send(data, data.length, host. DiscardUDPClient.DEFAULT_PORT)</code>.
    093     * @param data the buffer to send
    094     * @param host the target host
    095     * @see #send(byte[], int, InetAddress, int)
    096     * @throws IOException if an error occurs
    097     ***/
    098    public void send(final byte[] data, final InetAddress host) throws IOException
    099    {
    100        send(data, data.length, host, DEFAULT_PORT);
    101    }
    102
    103}
    104