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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.io.OutputStreamWriter;
25 import java.io.PrintWriter;
26 import java.net.InetAddress;
27 import java.net.SocketException;
28 import java.time.Duration;
29
30 import org.apache.commons.net.echo.EchoTCPClient;
31 import org.apache.commons.net.echo.EchoUDPClient;
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40
41 public final class echo {
42
43 public static void echoTCP(final String host) throws IOException {
44 final EchoTCPClient client = new EchoTCPClient();
45 String line;
46
47
48 client.setDefaultTimeout(60000);
49 client.connect(host);
50 try {
51 System.out.println("Connected to " + host + ".");
52 final BufferedReader input = new BufferedReader(new InputStreamReader(System.in));
53 try (PrintWriter echoOutput = new PrintWriter(new OutputStreamWriter(client.getOutputStream()), true);
54 BufferedReader echoInput = new BufferedReader(new InputStreamReader(client.getInputStream()))) {
55 while ((line = input.readLine()) != null) {
56 echoOutput.println(line);
57 System.out.println(echoInput.readLine());
58 }
59 }
60
61 } finally {
62 client.disconnect();
63 }
64 }
65
66 public static void echoUDP(final String host) throws IOException {
67 int length, count;
68 byte[] data;
69 String line;
70 final BufferedReader input;
71 final InetAddress address;
72
73 input = new BufferedReader(new InputStreamReader(System.in));
74 address = InetAddress.getByName(host);
75 try (EchoUDPClient client = new EchoUDPClient()) {
76
77 client.open();
78
79 client.setSoTimeout(Duration.ofSeconds(5));
80 System.out.println("Ready to echo to " + host + ".");
81
82
83
84 while ((line = input.readLine()) != null) {
85 data = line.getBytes();
86 client.send(data, address);
87 count = 0;
88 do {
89 try {
90 length = client.receive(data);
91 }
92
93
94
95
96 catch (final SocketException e) {
97
98 System.err.println("SocketException: Timed out and dropped packet");
99 break;
100 } catch (final InterruptedIOException e) {
101
102 System.err.println("InterruptedIOException: Timed out and dropped packet");
103 break;
104 }
105 System.out.print(new String(data, 0, length));
106 count += length;
107 } while (count < data.length);
108
109 System.out.println();
110 }
111
112 }
113 }
114
115 public static void main(final String[] args) {
116
117 if (args.length == 1) {
118 try {
119 echoTCP(args[0]);
120 } catch (final IOException e) {
121 e.printStackTrace();
122 System.exit(1);
123 }
124 } else if (args.length == 2 && args[0].equals("-udp")) {
125 try {
126 echoUDP(args[1]);
127 } catch (final IOException e) {
128 e.printStackTrace();
129 System.exit(1);
130 }
131 } else {
132 System.err.println("Usage: echo [-udp] <hostname>");
133 System.exit(1);
134 }
135
136 }
137
138 }