discardudpclient.java

来自「apache推出的net包」· Java 代码 · 共 94 行

/*
 * 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.apache.commons.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);
    }

}