001: /*
002: * Copyright 2001-2005 The Apache Software Foundation
003: *
004: * Licensed under the Apache License, Version 2.0 (the "License");
005: * you may not use this file except in compliance with the License.
006: * You may obtain a copy of the License at
007: *
008: * http://www.apache.org/licenses/LICENSE-2.0
009: *
010: * Unless required by applicable law or agreed to in writing, software
011: * distributed under the License is distributed on an "AS IS" BASIS,
012: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013: * See the License for the specific language governing permissions and
014: * limitations under the License.
015: */
016: package examples;
017:
018: import java.io.BufferedReader;
019: import java.io.IOException;
020: import java.io.InputStreamReader;
021: import java.io.InterruptedIOException;
022: import java.io.OutputStreamWriter;
023: import java.io.PrintWriter;
024: import java.net.InetAddress;
025: import java.net.SocketException;
026: import org.apache.commons.net.EchoTCPClient;
027: import org.apache.commons.net.EchoUDPClient;
028:
029: /***
030: * This is an example program demonstrating how to use the EchoTCPClient
031: * and EchoUDPClient classes. This program connects to the default echo
032: * service port of a specified server, then reads lines from standard
033: * input, writing them to the echo server, and then printing the echo.
034: * The default is to use the TCP port. Use the -udp flag to use the UDP
035: * port.
036: * <p>
037: * Usage: echo [-udp] <hostname>
038: * <p>
039: ***/
040: public final class echo {
041:
042: public static final void echoTCP(String host) throws IOException {
043: EchoTCPClient client = new EchoTCPClient();
044: BufferedReader input, echoInput;
045: PrintWriter echoOutput;
046: String line;
047:
048: // We want to timeout if a response takes longer than 60 seconds
049: client.setDefaultTimeout(60000);
050: client.connect(host);
051: System.out.println("Connected to " + host + ".");
052: input = new BufferedReader(new InputStreamReader(System.in));
053: echoOutput = new PrintWriter(new OutputStreamWriter(client
054: .getOutputStream()), true);
055: echoInput = new BufferedReader(new InputStreamReader(client
056: .getInputStream()));
057:
058: while ((line = input.readLine()) != null) {
059: echoOutput.println(line);
060: System.out.println(echoInput.readLine());
061: }
062:
063: client.disconnect();
064: }
065:
066: public static final void echoUDP(String host) throws IOException {
067: int length, count;
068: byte[] data;
069: String line;
070: BufferedReader input;
071: InetAddress address;
072: EchoUDPClient client;
073:
074: input = new BufferedReader(new InputStreamReader(System.in));
075: address = InetAddress.getByName(host);
076: client = new EchoUDPClient();
077:
078: client.open();
079: // If we don't receive an echo within 5 seconds, assume the packet is lost.
080: client.setSoTimeout(5000);
081: System.out.println("Ready to echo to " + host + ".");
082:
083: // Remember, there are no guarantees about the ordering of returned
084: // UDP packets, so there is a chance the output may be jumbled.
085: while ((line = input.readLine()) != null) {
086: data = line.getBytes();
087: client.send(data, address);
088: count = 0;
089: do {
090: try {
091: length = client.receive(data);
092: }
093: // Here we catch both SocketException and InterruptedIOException,
094: // because even though the JDK 1.1 docs claim that
095: // InterruptedIOException is thrown on a timeout, it seems
096: // SocketException is also thrown.
097: catch (SocketException e) {
098: // We timed out and assume the packet is lost.
099: System.err
100: .println("SocketException: Timed out and dropped packet");
101: break;
102: } catch (InterruptedIOException e) {
103: // We timed out and assume the packet is lost.
104: System.err
105: .println("InterruptedIOException: Timed out and dropped packet");
106: break;
107: }
108: System.out.print(new String(data, 0, length));
109: count += length;
110: } while (count < data.length);
111:
112: System.out.println();
113: }
114:
115: client.close();
116: }
117:
118: public static final void main(String[] args) {
119:
120: if (args.length == 1) {
121: try {
122: echoTCP(args[0]);
123: } catch (IOException e) {
124: e.printStackTrace();
125: System.exit(1);
126: }
127: } else if (args.length == 2 && args[0].equals("-udp")) {
128: try {
129: echoUDP(args[1]);
130: } catch (IOException e) {
131: e.printStackTrace();
132: System.exit(1);
133: }
134: } else {
135: System.err.println("Usage: echo [-udp] <hostname>");
136: System.exit(1);
137: }
138:
139: }
140:
141: }
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