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