import java io import java net import java nio import java nio channel

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import java.io.*;
import java.net.*;
import java.nio.*;
import java.nio.channels.*;
import java.nio.charset.*;
import java.util.*;
import java.util.regex.*;
public class TimeServer {
// We can't use the normal daytime port (unless we're running as root,
// which is unlikely), so we use this one instead
private static int PORT = 8013;
// The port we'll actually use
private static int port = PORT;
// Charset and encoder for US-ASCII
private static Charset charset = Charset.forName("US-ASCII");
private static CharsetEncoder encoder = charset.newEncoder();
// Direct byte buffer for writing
private static ByteBuffer dbuf = ByteBuffer.allocateDirect(1024);
// Open and bind the server-socket channel
//
private static ServerSocketChannel setup() throws IOException {
ServerSocketChannel ssc = ServerSocketChannel.open();
InetSocketAddress isa = new InetSocketAddress(InetAddress.getLocalHost(), port);
ssc.socket().bind(isa);
return ssc;
}
// Service the next request to come in on the given channel
//
private static void serve(ServerSocketChannel ssc) throws IOException {
SocketChannel sc = ssc.accept();
try {
String now = new Date().toString();
sc.write(encoder.encode(CharBuffer.wrap(now + "\r\n")));
System.out.println(sc.socket().getInetAddress() + " : " + now);
sc.close();
} finally {
// Make sure we close the channel (and hence the socket)
sc.close();
}
}
public static void main(String[] args) throws IOException {
if (args.length > 1) {
System.err.println("Usage: java TimeServer [port]");
return;
}
// If the first argument is a string of digits then we take that
// to be the port number
if ((args.length == 1) && Pattern.matches("[0-9]+", args[0]))
port = Integer.parseInt(args[0]);
ServerSocketChannel ssc = setup();
for (;;)
serve(ssc);
}
}