Java tutorial
/* * Copyright 2001-2005 The Apache Software Foundation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.eredlab.g4.ccl.net; import java.io.IOException; import java.net.DatagramPacket; import java.net.InetAddress; /*** * The DiscardUDPClient class is a UDP implementation of a client for the * Discard protocol described in RFC 863. To use the class, * just open a local UDP port * with {@link org.apache.commons.net.DatagramSocketClient#open open } * and call {@link #send send } to send datagrams to the server * After you're done sending discard data, call * {@link org.apache.commons.net.DatagramSocketClient#close close() } * to clean up properly. * <p> * <p> * @author Daniel F. Savarese * @see DiscardTCPClient ***/ public class DiscardUDPClient extends DatagramSocketClient { /*** The default discard port. It is set to 9 according to RFC 863. ***/ public static final int DEFAULT_PORT = 9; DatagramPacket _sendPacket; public DiscardUDPClient() { _sendPacket = new DatagramPacket(new byte[0], 0); } /*** * Sends the specified data to the specified server at the specified port. * <p> * @param data The discard data to send. * @param length The length of the data to send. Should be less than * or equal to the length of the data byte array. * @param host The address of the server. * @param port The service port. * @exception IOException If an error occurs during the datagram send * operation. ***/ public void send(byte[] data, int length, InetAddress host, int port) throws IOException { _sendPacket.setData(data); _sendPacket.setLength(length); _sendPacket.setAddress(host); _sendPacket.setPort(port); _socket_.send(_sendPacket); } /*** * Same as * <code>send(data, length, host. DiscardUDPClient.DEFAULT_PORT)</code>. ***/ public void send(byte[] data, int length, InetAddress host) throws IOException { send(data, length, host, DEFAULT_PORT); } /*** * Same as * <code>send(data, data.length, host. DiscardUDPClient.DEFAULT_PORT)</code>. ***/ public void send(byte[] data, InetAddress host) throws IOException { send(data, data.length, host, DEFAULT_PORT); } }