com.groupbyinc.common.util.net.echo.EchoUDPClient Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.echo;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.InetAddress;
import org.apache.commons.net.discard.DiscardUDPClient;
/***
* The EchoUDPClient class is a UDP implementation of a client for the
* Echo protocol described in RFC 862. 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,
* then call {@link #receive receive } to receive echoes.
* After you're done echoing data, call
* {@link org.apache.commons.net.DatagramSocketClient#close close() }
* to clean up properly.
*
*
* @see EchoTCPClient
* @see DiscardUDPClient
***/
public final class EchoUDPClient extends DiscardUDPClient
{
/*** The default echo port. It is set to 7 according to RFC 862. ***/
public static final int DEFAULT_PORT = 7;
private final DatagramPacket __receivePacket = new DatagramPacket(new byte[0], 0);
/***
* Sends the specified data to the specified server at the default echo
* port.
*
* @param data The echo 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.
* @exception IOException If an error occurs during the datagram send
* operation.
***/
@Override
public void send(byte[] data, int length, InetAddress host)
throws IOException
{
send(data, length, host, DEFAULT_PORT);
}
/*** Same as send(data, data.length, host) ***/
@Override
public void send(byte[] data, InetAddress host) throws IOException
{
send(data, data.length, host, DEFAULT_PORT);
}
/***
* Receives echoed data and returns its length. The data may be divided
* up among multiple datagrams, requiring multiple calls to receive.
* Also, the UDP packets will not necessarily arrive in the same order
* they were sent.
*
* @return Length of actual data received.
* @exception IOException If an error occurs while receiving the data.
***/
public int receive(byte[] data, int length) throws IOException
{
__receivePacket.setData(data);
__receivePacket.setLength(length);
_socket_.receive(__receivePacket);
return __receivePacket.getLength();
}
/*** Same as receive(data, data.length) ***/
public int receive(byte[] data) throws IOException
{
return receive(data, data.length);
}
}