| /* |
| * 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 examples; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.io.InputStreamReader; |
| import java.io.InterruptedIOException; |
| import java.net.InetAddress; |
| import java.net.SocketException; |
| import org.apache.commons.net.CharGenTCPClient; |
| import org.apache.commons.net.CharGenUDPClient; |
| |
| /*** |
| * This is an example program demonstrating how to use the CharGenTCPClient |
| * and CharGenUDPClient classes. This program connects to the default |
| * chargen service port of a specified server, then reads 100 lines from |
| * of generated output, writing each line to standard output, and then |
| * closes the connection. The UDP invocation of the program sends 50 |
| * datagrams, printing the reply to each. |
| * The default is to use the TCP port. Use the -udp flag to use the UDP |
| * port. |
| * <p> |
| * Usage: chargen [-udp] <hostname> |
| * <p> |
| ***/ |
| public final class chargen |
| { |
| |
| public static final void chargenTCP(String host) throws IOException |
| { |
| int lines = 100; |
| String line; |
| CharGenTCPClient client = new CharGenTCPClient(); |
| BufferedReader chargenInput; |
| |
| // We want to timeout if a response takes longer than 60 seconds |
| client.setDefaultTimeout(60000); |
| client.connect(host); |
| chargenInput = |
| new BufferedReader(new InputStreamReader(client.getInputStream())); |
| |
| // We assume the chargen service outputs lines, but it really doesn't |
| // have to, so this code might actually not work if no newlines are |
| // present. |
| while (lines-- > 0) |
| { |
| if ((line = chargenInput.readLine()) == null) |
| break; |
| System.out.println(line); |
| } |
| |
| client.disconnect(); |
| } |
| |
| public static final void chargenUDP(String host) throws IOException |
| { |
| int packets = 50; |
| byte[] data; |
| InetAddress address; |
| CharGenUDPClient client; |
| |
| address = InetAddress.getByName(host); |
| client = new CharGenUDPClient(); |
| |
| client.open(); |
| // If we don't receive a return packet within 5 seconds, assume |
| // the packet is lost. |
| client.setSoTimeout(5000); |
| |
| while (packets-- > 0) |
| { |
| client.send(address); |
| |
| try |
| { |
| data = client.receive(); |
| } |
| // 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"); |
| continue; |
| } |
| catch (InterruptedIOException e) |
| { |
| // We timed out and assume the packet is lost. |
| System.err.println( |
| "InterruptedIOException: Timed out and dropped packet"); |
| continue; |
| } |
| System.out.write(data); |
| System.out.flush(); |
| } |
| |
| client.close(); |
| } |
| |
| |
| public static final void main(String[] args) |
| { |
| |
| if (args.length == 1) |
| { |
| try |
| { |
| chargenTCP(args[0]); |
| } |
| catch (IOException e) |
| { |
| e.printStackTrace(); |
| System.exit(1); |
| } |
| } |
| else if (args.length == 2 && args[0].equals("-udp")) |
| { |
| try |
| { |
| chargenUDP(args[1]); |
| } |
| catch (IOException e) |
| { |
| e.printStackTrace(); |
| System.exit(1); |
| } |
| } |
| else |
| { |
| System.err.println("Usage: chargen [-udp] <hostname>"); |
| System.exit(1); |
| } |
| |
| } |
| |
| } |
| |