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/*
* 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 examples;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.InterruptedIOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.SocketException;
import org.apache.commons.net.EchoTCPClient;
import org.apache.commons.net.EchoUDPClient;
/***
* This is an example program demonstrating how to use the EchoTCPClient
* and EchoUDPClient classes. This program connects to the default echo
* service port of a specified server, then reads lines from standard
* input, writing them to the echo server, and then printing the echo.
* The default is to use the TCP port. Use the -udp flag to use the UDP
* port.
* <p>
* Usage: echo [-udp] <hostname>
* <p>
***/
public class echo
{
public static final void echoTCP(String host) throws IOException
{
EchoTCPClient client = new EchoTCPClient();
BufferedReader input, echoInput;
PrintWriter echoOutput;
String line;
// We want to timeout if a response takes longer than 60 seconds
client.setDefaultTimeout(60000);
client.connect(host);
System.out.println("Connected to " + host + ".");
input = new BufferedReader(new InputStreamReader(System.in));
echoOutput =
new PrintWriter(new OutputStreamWriter(client.getOutputStream()), true);
echoInput =
new BufferedReader(new InputStreamReader(client.getInputStream()));
while ((line = input.readLine()) != null)
{
echoOutput.println(line);
System.out.println(echoInput.readLine());
}
client.disconnect();
}
public static final void echoUDP(String host) throws IOException
{
int length, count;
byte[] data;
String line;
BufferedReader input;
InetAddress address;
EchoUDPClient client;
input = new BufferedReader(new InputStreamReader(System.in));
address = InetAddress.getByName(host);
client = new EchoUDPClient();
client.open();
// If we don't receive an echo within 5 seconds, assume the packet is lost.
client.setSoTimeout(5000);
System.out.println("Ready to echo to " + host + ".");
// Remember, there are no guarantees about the ordering of returned
// UDP packets, so there is a chance the output may be jumbled.
while ((line = input.readLine()) != null)
{
data = line.getBytes();
client.send(data, address);
count = 0;
do
{
try
{
length = client.receive(data);
}
// Here we catch both SocketException and InterruptedIOException,
// because even though the JDK 1.1 docs claim that
// InterruptedIOException is thrown on a timeout, it seems
// SocketException is also thrown.
catch (SocketException e)
{
// We timed out and assume the packet is lost.
System.err.println(
"SocketException: Timed out and dropped packet");
break;
}
catch (InterruptedIOException e)
{
// We timed out and assume the packet is lost.
System.err.println(
"InterruptedIOException: Timed out and dropped packet");
break;
}
System.out.print(new String(data, 0, length));
count += length;
}
while (count < data.length);
System.out.println();
}
client.close();
}
public static final void main(String[] args)
{
if (args.length == 1)
{
try
{
echoTCP(args[0]);
}
catch (IOException e)
{
e.printStackTrace();
System.exit(1);
}
}
else if (args.length == 2 && args[0].equals("-udp"))
{
try
{
echoUDP(args[1]);
}
catch (IOException e)
{
e.printStackTrace();
System.exit(1);
}
}
else
{
System.err.println("Usage: echo [-udp] <hostname>");
System.exit(1);
}
}
}
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apache_net.zip( 395 k)