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/*
* Copyright (c) 2004 David Flanagan. All rights reserved.
* This code is from the book Java Examples in a Nutshell, 3nd Edition.
* It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied.
* You may study, use, and modify it for any non-commercial purpose,
* including teaching and use in open-source projects.
* You may distribute it non-commercially as long as you retain this notice.
* For a commercial use license, or to purchase the book,
* please visit http://www.davidflanagan.com/javaexamples3.
*/
//package je3.net;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
/**
* This program is a very simple Web server. When it receives a HTTP request it
* sends the request back as the reply. This can be of interest when you want to
* see just what a Web client is requesting, or what data is being sent when a
* form is submitted, for example.
*/
public class HttpMirror {
public static void main(String args[]) {
try {
// Get the port to listen on
int port = Integer.parseInt(args[0]);
// Create a ServerSocket to listen on that port.
ServerSocket ss = new ServerSocket(port);
// Now enter an infinite loop, waiting for & handling connections.
for (;;) {
// Wait for a client to connect. The method will block;
// when it returns the socket will be connected to the client
Socket client = ss.accept();
// Get input and output streams to talk to the client
BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
PrintWriter out = new PrintWriter(client.getOutputStream());
// Start sending our reply, using the HTTP 1.1 protocol
out.print("HTTP/1.1 200 \r\n"); // Version & status code
out.print("Content-Type: text/plain\r\n"); // The type of data
out.print("Connection: close\r\n"); // Will close stream
out.print("\r\n"); // End of headers
// Now, read the HTTP request from the client, and send it
// right back to the client as part of the body of our
// response. The client doesn't disconnect, so we never get
// an EOF. It does sends an empty line at the end of the
// headers, though. So when we see the empty line, we stop
// reading. This means we don't mirror the contents of POST
// requests, for example. Note that the readLine() method
// works with Unix, Windows, and Mac line terminators.
String line;
while ((line = in.readLine()) != null) {
if (line.length() == 0)
break;
out.print(line + "\r\n");
}
// Close socket, breaking the connection to the client, and
// closing the input and output streams
out.close(); // Flush and close the output stream
in.close(); // Close the input stream
client.close(); // Close the socket itself
} // Now loop again, waiting for the next connection
}
// If anything goes wrong, print an error message
catch (Exception e) {
System.err.println(e);
System.err.println("Usage: java HttpMirror <port>");
}
}
}
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