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18 package org.apache.commons.net.examples.unix;
19
20 import java.io.BufferedReader;
21 import java.io.IOException;
22 import java.io.InputStreamReader;
23 import java.io.InterruptedIOException;
24 import java.net.InetAddress;
25 import java.net.SocketException;
26 import java.time.Duration;
27
28 import org.apache.commons.net.chargen.CharGenTCPClient;
29 import org.apache.commons.net.chargen.CharGenUDPClient;
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38 public final class chargen {
39
40 public static void chargenTCP(final String host) throws IOException {
41 int lines = 100;
42 String line;
43 final CharGenTCPClient client = new CharGenTCPClient();
44
45
46 client.setDefaultTimeout(60000);
47 client.connect(host);
48 try (final BufferedReader chargenInput = new BufferedReader(new InputStreamReader(client.getInputStream()))) {
49
50
51
52
53 while (lines-- > 0) {
54 if ((line = chargenInput.readLine()) == null) {
55 break;
56 }
57 System.out.println(line);
58 }
59 }
60 client.disconnect();
61 }
62
63 public static void chargenUDP(final String host) throws IOException {
64 int packets = 50;
65 byte[] data;
66 final InetAddress address;
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68 address = InetAddress.getByName(host);
69 try (CharGenUDPClient client = new CharGenUDPClient()) {
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71 client.open();
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74 client.setSoTimeout(Duration.ofSeconds(5));
75
76 while (packets-- > 0) {
77 client.send(address);
78
79 try {
80 data = client.receive();
81 }
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83
84
85
86 catch (final SocketException e) {
87
88 System.err.println("SocketException: Timed out and dropped packet");
89 continue;
90 } catch (final InterruptedIOException e) {
91
92 System.err.println("InterruptedIOException: Timed out and dropped packet");
93 continue;
94 }
95 System.out.write(data);
96 System.out.flush();
97 }
98
99 }
100 }
101
102 public static void main(final String[] args) {
103
104 if (args.length == 1) {
105 try {
106 chargenTCP(args[0]);
107 } catch (final IOException e) {
108 e.printStackTrace();
109 System.exit(1);
110 }
111 } else if (args.length == 2 && args[0].equals("-udp")) {
112 try {
113 chargenUDP(args[1]);
114 } catch (final IOException e) {
115 e.printStackTrace();
116 System.exit(1);
117 }
118 } else {
119 System.err.println("Usage: chargen [-udp] <hostname>");
120 System.exit(1);
121 }
122
123 }
124
125 }